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765 K.V., 400 K.V., 220 K.V., 132 K.V. to 33 K.V. All voltage class substation

Electrical job both (AIS / GIS) substation civil jobs, heavy transformer

Office :Avinandan Market, Ground Floor

9, Jessore Road, Duckbanglow MoreP.O. Hridaypur, Barasat, Kolkata - 700 127

Mobile : 98311 40082, 86172 88960E-mail : [email protected]

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LOADING, UNLOADING, DRAGGING & TRANSPORTING, OVERHAULING

ANNUAL JOURNAL 2020 Cover-1


Contractors, Builders and P.C.C Pole Manufacturers of WBSEDCL (S.S.I. Unit)

Factory :P.O. Jhunka (Beldanga)Murshidabad (W.B.)

Head Office :P.O. Barua (Beldanga)

Murshidabad - 742 189, (W.B.)

Cover-2 WBSEB ENGINEERS’ ASSOCIATION

Office :Vill. + P.O. Barua, P.S. BeldangaDist. Murshidabad, Pin - 742 189

Vill. + P.O. Majhyampur, P.S. BeldangaDist. Murshidabad, Pin - 742 189

Mobile : 97338 06113


Regd. No. 17716, Vendor Code : 513867

GST Code : 19BDXPM9333H1ZQ

INDIA & CO.

Regd. OfficeDurlovepur, P.O. MadhupurP.S. Nowda, Murshidabad


Abasbari, Tamluk, Purba MedinipurMobile : 94341 18871

E-mail : [email protected]

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ELECTRICAL CONTRACTOR


Vill. Padumbasan, P.O. Tamluk (Ward No. 11)Dist. Purba MedinipurMobile : 97337 46503


GOVT. LICENCED & ELECTRICAL CONTRACTOR

House Electric Wiring, Fan Motor Repairing & General Orders Supplier

WBSEDCL Enlisted, G.P.S. Survey Specialist


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Transformer Repair Capacity 11KV upto 630 KVA &

Type : Stack Core/Wound Core/33Kv Station service

Enlisted of : W.B.S.E.D.C.L.

GOVT. ELECTRICAL CONTRACTOR & GENERAL ORDER SUPPLIER

Office :

At. Pratapdighi, P.O. Pratapdighi

P.S. Patashpur, Dist. Purba Medinipur

Pin - 721 440

Factory :

At. Kharikapatna, P.O. Pratapdighi

P.S. Patashpur, Dist. Purba Medinipur

Pin - 721 440


Khoskhana, Demarihat, Purba MedinipurPhone : (03228) 258260, Mobile : 94341 10803

ELECTRICAL CONTRACTOR

WBSEDCL


Vill. Khoskhana, P.O. DemarihatDist. Purba MedinipurMobile : 94340 23781

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Vill. Nonakuri, BallukhatDist. Purba Medinipur


Dhamtouri, Simulia, Purba MedinipurMobile : 97328 36726


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Mobile : 94340 05395E-mail : [email protected]

mahakaliengineering @yahoo.com

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TECHNICAL JOURNAL

WEST BENGAL STATEELECTRICITY BOARD

ENGINEERS’ ASSOCIATION

ANNUAL JOURNAL 2020 1

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MR. AMIT KUMAR ADHIKARY

CIVIL & ELECTRICAL (GOVT. CONTRACTOR),

TRANSFORMER & GENERAL ORDER SUPPLIERS

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Head Office :Vill. & P.O. Deulia, Dist. Purba Medinipur, Pin - 721 154

Mobile : 94753 27068, 70636 48227, 96149 30109

Branch Office :Vill. Dakshin Mathura, P.O. Badalpur,P.S. Sabang, Dist. Paschim Medinipur

2 WBSEB ENGINEERS’ ASSOCIATION

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CENTRAL EXECUTIVE COMMITTEE 2018-20

PRESIDENT : Er. Ajay Kr. Das Mahapatra

VICE PRESIDENT : Er. Anil Kumar Pandey

Er. Nikhil Chandra Sarkar

HONY. SECRETARY : Er. Moupali Mukhopadhyay

HONY. ASST. SECRETARY : Er. Tanvir Hassan Syed

HONY. TREASURER : Er. Bidyut Bera

HONY. ASST. TREASURER : Er. Aman Mishra

MEMBERS

Er. Biplab Biswas, Er. Dilip Kumar Saha

Er. Himachal Kundu, Er. Jibanlal Mallik

Er. Mainak Ghosh, Er. Prasun Bhowmik

Er. Rabisankar Banerjee, Er. Suparna Sen

Er. Tapabrata Pyne, Er. Debraj Batayabal

Er. Ushnish Ranjan Chatterjee

CO-OPTED MEMBERS

Er. Mrinal Kanti Das, Er. Amitava Bardhan Roy

WEST BENGAL STATE ELECTRICITY BOARD ENGINEERS’ ASSOCIATION

ZONAL SECRETARIES 2019-20

BARDHAMAN

Er. Koushik Mondal

SALT LAKE

Er. Debayan Mandal

BANKURA

Er. Endadul Mondal

NADIA

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BIDYUT BHAVAN

Er. Hafsa Rahman

MALDA

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BAHARAMPUR

Er. Shubhadeep Roy

PPSP

Er. Sourav Laha

HOOGHLY

Er. Sajib Mondal

24 PARGANAS (S)

Er. Sadique Islam

SILIGURI

Er. Malay Roy

24 PARGANAS (N)

Er. Abdul Mahboob

MIDNAPUR

Er. Aritra Banerjee

RAMMAM

Er. Sonam Jamatsho Dupka

TAMLUK

Er. Santu Dutta

HOWRAH

Er. Tanmoy Ganguly


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Cell : 94343 21196, 98312 64503Fax : 033-2352 0009


SARAT CHANDRA MAITY(Proprietor)


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Editorial 2020

The mankind across the globe is facing an unprecedented crisis since World War-II with the onset

of COVID-19 pandemic. More than 45million people have been prey to the dreaded scourge and

over 1.2 million people have lost their precious lives so far. Scientists all across the continents are

struggling against time to find out vaccine to save the human race. Despite all we have to accept

the reality and adapt with the new normal. People around the world are fighting the battle and

hoping for a turn around by the next almanac. The business world has swiftly started to reinvent

itself with the changing times. The new generation have magnificently adapted themselves with

various on line virtual meet platforms viz. Zoom, Google meet, MS Teams, Webex etc to overcome

the disruption.

However, the technology field is already accustomed to face disruption caused by technology itself

particularly with the advent of new millennium. The disruptive technologies are indeed shaping

our future. There are lots of emerging technologies in the entire spectrum but a few like Artificial

Intelligence, Machine learning, Block Chain, Internet of Things(IoT), Cloud Computing, Social

Networking, 3D Printing are having immense effect towards driving the change. The disruptive

technologies are displacing the established technology and shaking up the industry e.g. the smart

meter has transformed the entire domain of meter manufacturing. Nowadays an energy meter is

not a simple meter but it has the capability to tell us so many parameters of the consumer and its

locality. It may tell us the weather condition of the locality by simply logging temperature, humidity

etc with the help of some additional sensors. It will give indication about intensity of sunlight if

connected to a roof top solar plant or it will give information about intensity of wind flow if

connected to a wind mill. It may give instant indication whether the consumer is away from home

or the precise time if someone is stealing power.

In power sector some emerging technologies and solutions are creating buzz nowadays viz. Wireless

long distance power transmission, Off-Grid Utility Scale Battery Storage, Voltage Source Converter

of HVDC network, Real Time Condition Monitoring and Management, ADMS (Advanced Distribution

Management System) etc. The outcome of the various cutting edge technologies and solutions

indicates the strength of software and it appears to be more powerful than hardware. A static

meter as hardware can only perform data logging but a meter coupled with software and

communication medium can perform lot more activities. It can act as connect-disconnect switch,

can act as informer to utility for system outage, power theft etc. The same hardware can be used

as prepaid or post paid meter with the presence of software unlike usual prepaid meter.

There are many differing opinions on the future of technology and how it will impact our lives.

Some people say that it’ll lead us to drive productivity, help us live longer, and increase efficiencies.

Others see the emergence of these technologies as a destructive catalyst that’ll have negative impact

upon society. Although it’s not a satisfying conclusion, reality rarely ends up on either side of a

binary like good/bad. Only time will have the appropriate answer.

Hope the next edition will see us back in old normal after winning the battle against the pandemic

hitherto unseen to all cross section of the society. We must remain mentally strong, physically fit

and always on the move. However, we may remember the unforgettable quote from “War & Peace”

by the great litterateur Leo Tolstoy — “The strongest of all warriors are these two-Time and

Patience”.

(Er. Sumit Mukherjee)

Editor, Journal 2020


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]

STATE ELECTRIC CO.GOVT. LICENSED ELECTRICAL CONTRACTOR &

NETWORK CABLING WORKS

Nabghara Amta Road Jn., N.H.-6, Howrah - 711 322

Phone : 2661 6873, Fax : (033) 2661 7863E-mail : [email protected]

SEC


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Journal Sub-CommitteeEditor Er. Sumit Mukherjee

Convenor Er. Sukanta Biswas

Members Er. Suparna Sen

Er. Himachal Kundu

Er. Tanvir Hassan Syed

Er. Soumitra Biswas

Er. Sayan Bhattacharyya

Er. Rounak Jain

PublisherEr. Moupali Mukhopadhyay

Hony. Secretary, WBSEBEA

Cover DesignEr. Prabir Pal

A Production ofMedia SS

8B, Monohar Pukur 2nd Lane, Kolkata - 700 029

Phone : 98306 10609

_ GRATITUDE

v Contributors of ArticlesContributors of ArticlesContributors of ArticlesContributors of ArticlesContributors of Articles

for their sincere and merited response

v All AdvertisersAll AdvertisersAll AdvertisersAll AdvertisersAll Advertisers

for expressing themselves through our pages and helping our resources

v Media SS – the Printerthe Printerthe Printerthe Printerthe Printer

for endeavouring their best to implement what we nurtured


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@

MAZUMDER ELECTRICALSA Contractor of Electrical, Civil Works &

General Order Supplier

114/18, Rabindra Sarani, P.O. BhattanagarLiluah, Howrah

Phone : (03214) 269009Mobile : 97324 38023, 97327 12425


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INFORMATION SECURITY: A RINGING BELL! 11 ER. AMLAN SARKAR

PREPAID METER 19 ER. SOURAV ROY

A BRIEF ON CURRENT OPERATED 23 ER. SOUMYAJIT DHARA

PROTECTION FOR POWER TRANSFORMER

TESTING AFTER ASSEMBLY OF THE 27 ER. SANJIT CHAKRABORTYTRANSFORMER AT SITE

SCHEDULING, ACCOUNTING, METERING AND 33 ER. AMITAVA NAGSETTLEMENT OF POWER BY SLDC

ACCORDING TO THE REPORT OF FORUMOF REGULATORS (FOR) ON SAMAST

PUBLISHED IN JULY’2016

Contents


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+

A. C. CONSTRUCTIONCivil, Electrical, Mechanical Contractor &


License No. - 14411, Enlisted by W.B.S.E.D.C.L.

Rajarampur, Sibaramnagar, SutahataPurba Medinipur, Pin - 721 635



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INFORMATION SECURITY: A RINGING BELL!

ER. AMLAN SARKAR, DE (IT&C)

Central Data Centre, Rajarhat, WBSEDCL

Information Security very commonly known as

Infosec,has evolved to become highly important

aspect for every organization over last few years.

Organizations have started to show due priority and

attentions by deploying expert manpower in

Information security domain. Extreme emphasis

has been intensified from various Government

authorities. But why so? Is this intensity very rapid

and sudden?

To find the answer, first let us understand what

information security is. Information Security is the

process of preventing inappropriate malicious

intentions,unauthorized access, use, disclosure,

devaluation,disruption, deletion, modification,

corruption, inspection, recording or destruction,

and protect ion of information by mit igat ing

information risks. It is designed to protect the

confidentiality, integrity and availability of system

data (sometimes referred to as the CIA Triad of

information security). These objectives ensure that

sensitive information is only disclosed to authorized

users (confidentiality), prevent unauthorized

change or modification of data (integrity) and

guarantee that the data can be accessed only by

authorized users when requested (availability).

Though Information being both physical and

digi tal , however, with the advancement of

information technology, automation and artificial

intelligence, digital data has become essential for

every organization. From financial organizations to

scient i f ic research units, f rom defense to

telecommunication, from production to service

across all the industrial sectors, digital information

or data has become indispensable for almost all

the organizations, thus making it the backbone of

a nation. Organizations of every size and type, has

its operational and business data on which it relies

for day to day operations, decisions making and

also building strong strategies for future path.

Hence such data is not only confidential but critical

and sensi t ive. And that is the reason why

information security has become essential.

As we understand the need of the information

security, let us now understand who the potential

attackers are, what the threats are, what are the

reasons and methods of attacks, and what are the

preventive measures to mitigate such attacks.

Attackers commonly known as information hackers

or Cyber Attackers are the individual experts or

organization who uses their technical knowledge

and performs the malicious activities to destroy,

expose, alter, disable, steal or gain unauthorized

access to damage or harm the data that is highly

vulnerable & important. They use several hacking

tools or methods to explore the vulnerability of a

network or a system, to damage the entire system

or ensure that the important data can be lost. Some

very common threats to information security are

Virus, Spyware, Trojan, Worms etc.

One obvious question comes in mind, why

hackers attempt to break into systems and

networks? What could be the possible motive?

Well, just like real-life criminals, cyber-criminals are

motivated by a variety of goals. These are some of

the probable possibilities.

First obvious reason is financial gain. Financial

motives are among the largest reasons for targeting

an organization or individual. In this type of attacks,

the hacker either steals the financial/banking

information and makes diversion of funds from their

legitimate destination to a fraudster’s account or

hackers takeover a victim’s critical data and freeze

it, they then offer to reinstate access after a ransom

has been paid.Though it may sound very surprising

but some cyber-criminals enjoy the thrill of making

successful cyber-attacks on major organizations.

They see it as recognition of their hacking abilities.

Cyber-criminals in this category are usually

teenagers. Most of them carry out cyber-attacks

just for fun and entertainment. To them, launching

a successful attack would earn them respect and

honour or increase their reputation from the online

hacking community.


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One of the major reasons of such attack is

hacktivism. Hacktivists are individuals or groups

of hackers who carry out malicious activity to

promote a political agenda, religious belief, or

social ideology. Some cyber-criminals are strong

supporters of certain political views or religious

movements. Thus, they carry out cyber-attacks to

make their pol i t ical /rel ig ious views known.

Hacktivists are not like cyber criminals who hack

computer networks to steal data for the cash. They

are individuals or groups of hackers who work

together and see themselves as fighting injustice.

There are many more reasons. Cyber-criminals

might act out of anger and revenge. These might

include retrenched employees who are forced to

leave the organization or displeased or dissatisfied

with the organization. One of the very common

attackers are insider-threat. As the name suggests,

it is a threat to an organization’s security that comes

from within, usually occurring from employees or

former employees, but may also arise from third

parties, including contractors, temporary workers,

vendors or customers. Even emotions sometimes

lead people into cybercrimes, though the numbers

of these sorts of attackers are significantly low

compared to the others.

State-sponsored attacks provide nation states with

both wartime and intelligence collection options.

State-sponsored attackers have particular objectives

aligned with either the political, commercial or military

interests of their country of origin.

Finally, whether the manufacturing companies

of security appliances (such as firewalls, antivirus,

scanning devices, content filtering devices, IDS IPS

etc.) are behind the creation of all computer threats

to create a market for their products?Could

antivirus companies be the real originators of

viruses and malware? Could they be doing it

themselves, or paying other experts to come up

with the harmful software in order to increase their

profits? These questions have been asked over the

years.The question is quite similar to whether the

weapon manufacturing companies promote war?

Well, there is no such definite vindication or

evidence, though some people sincerely believe

the same. However, the argument seems

hypothetical and notional.

As we now understand the reasons or motives

of various attacks, let us now discuss some of the

most common cyber attacks that a business could

face.

1) Denial-of-Service (DoS) Attacks / Distributed

Denial-of-Service (DDoS) Attacks

As the term suggests, a Denial-of-Service (DoS)

attack is an attack meant to affect a system or

network, making it inaccessible to its intended

users. Here, attackers focus on disrupting the

services to a network or a system by flooding the

target with traffic. A high volume of data or traffic

across the network are being generated through

lots of connection requests until the network

becomes overloaded and can no longer be

functional or can trigger a crash. Basically it

overwhelms system/network resources so that it

cannot respond to service requests.

Figure : DDoS attacks

Attacker

Slaves

Victim

DDoS Attack


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Clearly that, DOS doesn’t provide direct benefits

for attackers in terms of gaining the access or

increase the control over system, but typically

functions by overwhelming or flooding a targeted

machine with requests until normal traffic is unable

to be processed, resulting in denial-of-service to

deprive the legitimate users.

A distributed denial-of-service (DDoS) attack is

a type of DoS attack that comes from many

distributed sources. A DDoS attack occurs when

multiple systems orchestrate a synchronized DoS

attack to a single target. The significant difference

with DOS is that, instead of being attacked from

one location, the target is attacked from many

locations at once, and hence, achieve effectiveness

by uti l izing multiple compromised computer

systems as sources of attack. It is much effective

for attackers as large numbers of systems are used

to execute the attack, the location of the attack is

difficult to detect due to the random distribution of

attacking systems and even more difficult to identify

the source of attack, as they are disguised behind

numbers of compromised systems. From a high

level, a DDoS attack is like a traffic jam clogging

up with highway, preventing regular traffic from

arriving at its desired destination.

There are different types of DoS and DDoS

attacks; the most common are: TCP SYN flood

attack, teardrop attack, Buffer overflow attacks,

ICMP flood, smurf attack, ping flood, ping-of-death

attack and botnets.

2) Man in the Middle (MITM) Attack

In a man-in-the-middle attack, attackers place

themselves between two devices/users and

intercept or modify communications between the

two. Generally, hacker inserts itself between the

communications of a client and a server by

establishing a separate route of communication.

Typically, the man in the middle would then try

to steal all the information transferred between both

parties, which could include sensitive data, such

as f inancial , personal information, system

information or user login credentials. Sometimes

they snoop on private conversations, which might

be critical or sensitive and might include trade

secrets or other valuable information.

MITM is very effective for attackers as they gain

control of the client either by disconnecting the

client from the server or replacing the client

machine and continues dialog with the server and

the server believes it is still communicating with

the client. According to various studies, worldwide

35% of exploitation activity involved attackers

attempting MITM attacks. Some well known MITM

attack is Email Hijacking, Wi-Fi Eavesdropping,

Session Hijacking, DNS Spoofing, IP Spoofing,

ARP Spoofing, Man-in-the-Browser etc.

3) Phishing Attacks

Phishing attacks are the fraudulent

communicat ions that appear to come from

reputable sources. It is a type of social engineering

attack often used to steal sensitive user data such

as financial information or login credentials. It is

usually done through emails, instant messages, or

text messages. It starts with a fraudulent email or

other communication that is designed to lure a

victim. An attacker, masquerading as a trusted

entity, dupes a victim into opening an email, instant

Figure : Classical examples of Man in the Middle attacks

User

new

connection

new

connection

Hacker

original connection User

MITM ATTACK

ORIGINAL CONNECTION

WEB APPLICATIONUser/

Victim

MAN IN THE MIDDLE

MW C

onnection

MW Connection

HOW MAN IN THE MIDDLE ATTACKS WORK


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message, or text message. The message is made

to look as though it comes from a trusted sender.

It fools the victim, and the victim is coaxed into

providing confidential information, often on a scam

website. Sometimes malware is also downloaded

onto the target’s computer. The recipient is tricked

into clicking a malicious link, which can lead to the

installation of malware, the freezing of the system

as part of a Ransomware attack or the revealing of

sensitive information.

Phishing is a very common type of cyber attack.

Emai l phishing, Decept ive phishing, Spear

phishing, Whaling, Pharming, Smishing (over

SMS), and Vishing (over telephone calls) are some

of the commonly known phising techniques.

4) Password Attacks

A password attack is exactly what the name

sounds like. Because passwords are the most

commonly used mechanism to authenticate users to

an information system, hence, obtaining passwords

is a common and effective attacking approach. Here,

attacker tries to gain access to systems by cracking

a user’s password. Access to a person’s password

can be obtained by connecting the network to acquire

unencrypted passwords, gaining access to a

password database or outright guessing. Attackers

use many methods to access information such as

Key Logger, Brute Force or Dictionary Attack.

A hacker uses a program to track all of a user’s

keystrokes and captures everything that the user

has typed including their login IDs and passwords,

which is known as Key Logger attack. A brute force

attacks made to guess passwords using a random

approach by trying different combinations of

passwords.

In a dictionary attack, a dictionary of common

passwords is used to attempt to gain access to a

Figure: Phishing Techniques

Figure : Password Attack


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user’s computer and network. It takes advantage

of the fact that the people tend to use common

words and short passwords. Another approach is

to copy an encrypted f i le that contains the

passwords, apply the same encryption to a

dictionary of commonly used passwords, and

compare the results.

5) SQL Injection Attacks

SQL injection is a type of attack generally

designed for database-driven websites. It is a code

injection technique which occurs when a malefactor

executes a SQL query to the database through a

client input to the target server in order to run

predefined SQL commands. A successful SQL

injection exploit can result in unauthorized access

to sensitive data (such as passwords, bank login

detai ls, or user login information) from the

database, modify ( insert, update or delete)

database, execute administration operations (such

as shutdown) on the database, recover the content

of a given f i le, and, in some cases, issue

commands to the operating system. In many cases,

an attacker can modify or delete data, causing

persistent changes to the application’s content or

behavior. An attacker can also escalate an SQL

injection attack to compromise the underlying server

or other back-end infrastructure, or perform a denial-

of-service attack. In some cases, an attacker can

obtain a persistent backdoor into an organization’s

systems, leading to a long-term compromise that can

go unnoticed for an extended period. SQL injection

is very common with PHP and ASP applications due

to the prevalence of older functional interfaces.

6) Cross Site Scripting (XSS) Attack

Cross-site scripting (also known as client-side

code injection attack) is a web security vulnerability

that al lows an attacker to compromise the

interactions that users have with a vulnerable

application. The attacker aims to execute malicious

scripts in a web browser of the victim by including

malicious code in a legitimate web page or web

application. The actual attack occurs when the

malicious code executes inside a victim’s browser,

the attacker can fully compromise their interaction

with the application. The web page or web

application becomes a carrier to deliver the

malicious script to the user’s browser. An attacker

can also use Cross-site scripting (XSS) to send a

malicious script to an unsuspecting user. The end

user’s browser considers the script to be trusted,

and executes the script. Because it thinks the script

came from a trusted source, the malicious script

can access any cookies, session tokens, or other

sensitive information retained by the browser.

7) Spoofing

Spoofing is the act of hiding identity of a

communication from an unknown source so that it

appears to be associated with authorized trusted

source. It is a frequently used attacking method.

Some common types of spoofing attacks are IP

address spoofing, Address Resolution Protocol

(ARP) spoofing, Domain Name System (DNS)

spoofing etc. These types of spoofing attacks are

used to access confidential information, to attack

networks or to spread malwares.

Figure : Cross Site Scripting (XSS)


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8) MAC flooding

The MAC Flooding (Media Access Control) is a

commonly used network attacking method which is

designed to compromise the security of the network

switches. It is the method of attacking the network

switches and not a method of typically attacking any

host machine in the network directly. Here an attacker

connected to a switch port floods the switch interface

with very large number of Ethernet frames with

different fake source MAC addresses.

Switches connected to a network maintain a

table called MAC Table. This MAC Table contains

individual MAC addresses of the host computers

connected to network ports of the switch. This table

allows the switches to send the data through the

ports to the intended recipient. As we know that

switches send the data to the specific computer

where the data is intended to be sent but a hub

broadcasts the data to the entire network allowing

the data to reach all available hosts on the network.

Target of this attack is to convert the switch into a

hub and make it behave like a network hub. This

goal is achieved by taking down this table using

MAC table Flooding. The hacker first connects to

the switch ports and floods its interface by forcing

legitimate MAC addresses out of the MAC address

table by sending very large number of fake MAC

addresses. Once the MAC address table is full, it

is unable to save new MAC addresses. The network

switch enters into the fail-open mode and behaves

like a network hub.

Broadcasting all the packets on all the switch ports.

The hacker finally uses an packet analyzer to capture

various packets to steal the sensitive information.

9) Virus/ Malware attacks

Virus, malware, spyware, and ransomware are

very commonly used words nowadays to the

Computer users. What is a virus? Well, it is an

abbreviation which means “Vital Information

Resources Under Seize”. It is a human made piece

of code or a computer program which can load over

a computer on its own without user’s knowledge

and run against the consent. It has the ability to

replicate on its own and affect the whole system.

At times, it spreads itself even from one computer

Figure : MAC Flooding

Figure : Malware attacks

Spyware

Rootkit

Adware

Virus

Ransomware

Trojan horse

Remote access

Worm

Keylogger


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to another computer over the connected network.

It has the ability to affect the application, data files,

boot sector of hard drive etc. once the replication

is successful.

Malicious software, more commonly known as

malware, is an umbrella term for various types of

malicious programs which is designed to cause

damage through variety of cyber threats including

Trojans, viruses and worms. Malware is simply

defined as ‘code with malicious intent’ that typically

steals data or destroys something on the computer.

A wide variety of malware exist, including computer

viruses, worms, Trojan horses/Banking Trojans,

Keyloggers, Logic bombs, Droppers, Stealers,

remote access tool (RAT), ransomware, Backdoors,

spyware, adware, rogue software, Zombieware and

scareware.

Malware is most often introduced to a system

through email attachments, unknown links or

software downloads. One of the ways to attack a

target computer with malicious code is, when user

clicks on an affected advertisement in web. This is

known as Malvertising. A program is downloaded

to a user’s system just by visiting the site, known

as Drive-By Downloads attack. It doesn’t require

any type of action by the user to click a download

button or open a malicious email attachment to

become infected. Rogue securi ty sof tware

designers make pop-up windows and alerts that

look legitimate. These alerts advise the user to

download security software, agree to terms or

update their current system in an effort to stay

protected. By clicking “yes” to any of these

scenarios, the rogue software is downloaded to the

user’s computer.

As we are familiar with some common method of

attacks, now we must be aware of and vigilant toward

the mitigation, protection and prevention of various

threats or attacks. It is important to identify risks to

the IT systems to reduce or manage those risks, and

to develop a response plan in the event of an IT crisis.

There are some standard practices at user level as

well as at administrator level which needs to be

followed to keep the business information safe.

For system users passwords are an integral

aspect of our computer security program. Password

must be hard-to-guess and must be set using

uppercase/lowercase letters, numbers and special

characters. Different passwords are to be set for

different accounts so that, if one password gets

hacked, other accounts are not compromised.

Changing passwords periodically is a good

practice. User must not write down anywhere. Use

of Two-Factor Authentication is much safer, if the

facility is available. System must be in log-off mode

when not in use. Updating the system with latest

service packs/versions/patches of operating

system, application software, and the use of

updated anti-virus software with periodical scanning

are highly recommended. Keeping regular data

backups, USB access restriction for external media,

use of on-screen keyboard for entering sensitive

information, disabling remote Desktop access to

others, sharing of resources are also extremely vital

parameters of information security.

Downloading software only from reliable sources,

reading the permissions carefully before installing any

software, checking the URL before logging into any

site and ensuring that the URL of the site has HTTPS

can save us from phishing traps. One must not open

mail, a link or attachments from an untrusted source.

In case of a suspicious email, the best thing to do is

to delete the message, and report it to designated IT

security representative.

For system administrators the task is even more

challenging. They should have a regular and

constant monitoring over entire system. There are

many critical security parameters such as Use of a

Virtual Private Network (VPN), availability of

adequate bandwidth, redundancy into

infrastructure, high availability services, anti-DDoS

hardware and software modules, DNS protection,

Designing network with an intrusion detection/

Prevention system, Use of HTTPS encryption to

help detect and block spoofing attempts, analyzing

traffic patterns to identify unusual behavior,

restricting access and authorization among users,

blocking of unused IPs/Ports and moreover, use

of penetration testing tools to identify security

weaknesses and unknown vulnerabilities in a

network, server or web application that can cause

a security breach.

Finally, Information Technology is indispensable

for almost all the organizations nowadays. There

is no place to deny that without a backbone of

information technology, a business is not going to


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progress far in today’s world. The formula for

successful business is very simple: drive innovation

with information technology. That is the reason why,

IT systems of any organization has become the

epicenter to the attackers. Therefore, it is of utmost

importance to secure the critical data, and other IT

devices. Naturally it is the duty of every individual

of an organization to obey its security guidelines

and safeguard the IT systems.

Progress of an organization implacably requires

changes. Changes in terms of mentality, mindset

and adaptability of employees. One effective way

of bringing this change is raising the awareness to

obey security guidelines among all. Casual

approaches or neglect ing att i tude can be

dangerous; the world has already witnessed some

of such biggest security disasters.

“It is everyone’s responsibility to stand ready to

assist and support its organization in information

security risk management efforts. Everyone must

remember that information security is everyone’s

responsibility!”


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With Best Compliments FromWith Best Compliments FromWith Best Compliments FromWith Best Compliments FromWith Best Compliments From

RIMA ENTERPRISEGOVT. ENLISTED CONTRACTOR

Electrical & Mechanical Engineers & General Order Suppliers

58/4, Ashokenagar, P.O. Ashokenagar, Dist. North 24 Parganas, Pin - 743 222, W.B.Mobile : 95647 20120, 93320 40120, E-mail : [email protected]

Prepaid Energy Meter is a multipurpose project

which can integrate all the functions like billing and

automatic message response to the user. Before

knowing of prepaid Electrical billing system one has

to know the reason why and what is the need that

brought up this idea into existence.

Advantage of Prepaid billing system over

postpaid one :

i) The conventional method of Electricity billing

involves a person from the distribution unit

reading the number of Electricity unit consumed

(by the consumer) in the Energy Meter,

conveying this reading to the distribution unit

and then preparing the bill according to the

Energy consumed for a fixed amount of time.

This can prove quite tedious as it involves

various tasks like reading and preparing the

bill. Still Accuracy can’t be guaranteed as there

can be errors in human reading. With this

system the total billing consumes more time

and require more man power.

ii) Unpaid bills and outstanding will not be a

headache for the distribution unit which has a

grave impact in the company’s profit.

iii) The consumer will have a better resource

(Electricity unit) management in this ‘pay as

you go’ method as they will be able to see day

to day consumption in their prepaid Meter.

iv) As Prepaid Meters can be set to a load limit

beyond which it will automatically disconnect

the output, load drawal during pick load hours

can be controlled.

When the consumer buys electricity, he is given

an authorisation by means of an encrypted code.

This code issued to him in the form of a paper token

which is printed on any printer connected to PC or

through WEB based services. This code is used to

recharge the meter. This encrypted code contains

relevant information regarding to consumer

database, tariff, recharge amount arrear, rebate

etc. and stored in the meter memory. This

information is displayed on Meter & CIU (Consumer

PREPAID METER

ER. SOURAV ROY, AE(E)

Distribution Testing Department, WBSEDCL

Interface Unit) display. The Meter & the CIU have

keypad for amount transfer. Themeter is designed in

single box with measuring element, dual latching relay

for phase and neutral to escape fraud & disconnect

consumer load while credit expires and overloads.

Salient Features of Prepaid Meter :

i) Simple, numeric recharge codes similar to

mobile phone recharges.

ii) Current load cost and number of days left for

usage shown on display.

iii) User configurable alarm limits and timings for

low balance, no balance and no credit.

iv) Programmable fr iendly hours/days and

holidays (in which service will not be disconnect

even for zero balance), TOD tariff structure (if

applicable).

v) Customer interface unit (CIU) available for use

inside the home. It is connected with the Meter

by a 4 Wire connection cable (similar to

telephone cable)

vi) USB dongle token carrier for recharging meter

through CIU.

vii) Balance and consumption indication LED in CIU.

Block Diagram of Main Functional Units of

Prepaid Meter


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C D

Technical Features of Prepaid Meters :

i) In WBSEDCL we use single phase prepaid

Meters of 240V, 10-60A and 3 phase Meter of

3x240V, 20-80A (Whole current).

ii) The Meters are built with accuracy of class 1

as per IS 13779, 1999 read with its latest

amendments.

iii) WBSEDCL also follows CBIP report no 88 read

with latest amendments CBIP-304 which gives

specification for AC static Electrical Energy

Meter. For Direct Connected StaticPrepayment

Meters for Active Energy WBSEDCL follows IS

15884 (2010)

iv) The meter starts registering energy at 0.2 % of

basic current at unity power factor and first

pulse must be appeared within 10 minutes.

Running at no load: When 70% & 120% voltage

is applied and no current flows in the current

circuit, the test output of the meter should not

produce more than one pulse.

v) The meter is designed with ASIC (application

specific integrated circuit) and is manufactured

using SMT (Surface Mount Technology)

components. Power supply and voltage divider

circuits may be of PTH (Pin Through Hole)

technology.

vi) The meter is fitted with C.T. or SHUNT for

measuring current in the phase element. The

Neutral element may have either C.T. or

SHUNT or HALL EFFECT SENSOR with proper

isolation.

vii) The meter cover is permanently fixed to the

meter base by using ultrasonic welding.

viii) Customer Interface Unit (CIU) has high

resolution graphic display which is user friendly

and provides a host of information to the

consumers in tabular format with single key.

ix) Meter keypad has numeric from 1-9 and 0 with

a ‘*’ and a ‘#’ key like telephones having each

key displays various parameters when pressed.

x) Meter supports maximum of 8 rate registers

with maximum of 8 nonoverlapping time zones

in a day.

xi) The meter should have legible LCD with

starburst display for displaying alphanumeric

characters and information like Total credit

amount, credit balance, cumulative KWh. Slab

detai ls and their rates, current MD with

occurrence date & time.

xii) The meter should have facility of load limit

configuration by which if it exceeds result in

disconnection of consumer output supply.

xiii) Relay should be provided in both phase &

neutral element in the meter to let alone fraud

and single wire tamper. It should be bi-stable

type latching switch designed as per

international standard.

xiv) During Testing of Meter, it is to observe so that

the Meter withstands 450V between phase and

Neutral for 10 mins. After this test another test

to be carried out in which the Meter has to

endure 150% of Imax for 2 hours.

xv) A simplest type of Prepaid Energy Meter

consists of two EEPROMs interfaced to a

Microcontroller. One EEPROM contains the

recharge balance amount, the microcontroller

reads this balance amount and stores it in the

other EEPROM along with the tariff.

The Energy Meter supplies pulses to the

microcontrol ler for every unit of energy

consumed. The microcontroller increases the

spent energy unit by one and decreases the

balance amount of EEPROM by the fixed tariff.

As soon as the balance amount of the

EEPROM comes down to zero, the micro

controller sends a signal to the relay driver

which in turn switches of the relay, such that

the main supply to the load is switched off.

Working block diagram of Prepaid Energy Meter


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C D

Flowchart of Prepaid Meter Working Principle :


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C D


^

M/s. ESAR ENTERPRISE

GOVT. CIVIL & ELECTRICAL CONTRACTOR

CHANCHAL (THANA ROAD), DIST. MALDA

Contact :

94343 55521 (Biplab Sarkar)94343 55531 (Pradyut Ghosh)

Prop. : BIPLAB SARKAR


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A. Introduction

This is the most expensive equipment and most

important links in every power transmission unit.

Availability of power transformer is very essential

in transmission network to transfer power. The

choice of suitable protection is governed by

economical consideration; means for higher MVA

higher degree of protection is justified.

B. Nature and effects of faults in transformers

Fault magnitude is controlled by source, neutral

impedance and leakage reactance of transformer.

1. Star winding with neutral point solidly earthed:

In this cases fault current mainly depends on

the leakage reactance of the transformer and

varies in a peculiar manner with the position

of the fault. Voltage at the point of fault is an

important issue as the reactance decreases

rapidly when fault occur towards neutral point

of winding. The fault current is the highest near

the neutral point of winding.

2. Delta winding : Delta connected winding

should operate with a voltage to earth more

than 50% of phase voltage as the fault current

magnitude is less compared to star connected

winding. The value still depends on the way it

is earthed. It may be noted that the impedance

of a delta winding is high to the fault current

flowing to a centrally placed fault on one leg.

The impedance can be expected within 25-

50%, based on transformer rating. As in pre-

fault condition, voltage to earth at this point is

half the normal phase voltage; earth fault

current may be not more than the rated current

if system earthling impedance is appreciable.

The current will flow through each half winding

to the point of fault and will be divided between

two phases of the system.

C. Differential Protection

From 10 MVA and above transformer rating, we

have standardized to implement differential

A BRIEF ON CURRENT OPERATED PROTECTION

FOR POWER TRANSFORMER

ER. SOUMYAJIT DHARA, DE (TESTING)

protection in our system. The Merz-Price principle

is valid for system having more than two winding

(e.g for 400/220/33 kV Auto-transformer). It is to

be noted that bias setting to be given separately

for each i.e between HV-IV and HV-Tertiary.

When transformer has only one winding

connected to supply and other winding feeding

loads at various voltage level, the separated load

currents may be summated in CT secondary side

which will be balance with the supply end CT

secondary current.

But when it is connected to more than one

supply at various voltage levels, distribution of

current become complex and there is a possibility

of mal-operation due to circulating current between

two parallel set of current transformer without

producing any bias. So, it is safer to incorporate

separate bias coils between windings so that their

mechanical and electrical effects always become

3-WDG Transformer (One Power Source)

3-WDG Transformer (More than One Power Source)


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additive to generate total bias as per the scheme

discussed.

Zero-Sequence Current Subtraction : Zero

sequence current flowing on the star side will not

create any current on the outside of delta winding

in a star/delta power transformer. So it is become

essential to connect the CT secondary in ‘delta’

mode towards the star side of power transformer

to eliminate the zero sequence. Consequently, it

is become obvious to connect the CT secondary in

‘star’ mode at Delta side of power transformer to

provide 30o lag or lead phase shift according to

the vector group of power transformer.

Dual slope characteristic : Reputed manufactures

follow similar dual-slope characteristics to provide

an over-all stable transformer differential protection

with an user-defined Idiff (min)

, Slope-1, Slope- 2, Idiff

(High-set) etc. in modern numerical differential relays.

A setting calculation of differential relay on

150MVA, 220/132kV is given hereunder.

HV CT current at 231kV = 374.90/600 = 0.625 A.

HV CT current at 187kV = 463.128/600 = 0.772 A.

Ratio correction factor calculated at 231kV

side = 0.625x1.524 = 0.9522

Ratio correction factor calculated at 187kV

side = 0.772 x 1.524 = 1.176

Now, IDiff1

= | 1-0.952 | = 0.048; IDiff2

=

| 1.176-1 | = 0.176

Maximum of the two is 0.176, which is appox. 0.2,

IDiff (Min)

will be 0.2

Slope1 start point is fixed for some relays which

passes through (0,0) ordinate which eventually

depends on Idiff (min) value when calculated by

equation y=mx. It is generally recommended to set

around 1.0 -1.2 per unit of Bias current to keep a

FLAT slope in 100-120% normal loading region of

transformer.

Considering CT ratio at 220kV side is 600/1 A

CT ratio at 132kv side is 800/1 A.

Rated HV current is 393.659 A.

Rated LV current is 656.09 A.

HV CT sec current = 393.659/600 = 0.656 A.

LV CT sec current= 656.07/800 = 0.82 A.

Considering Tap setting = ±5%

Max. Voltage variation = 220 x 1.05 = 231 kV.

Min. Voltage variation = 220 x 0.85 = 187 kV.

Ratio correction factor calculated internally by relay

to obtain 1 A at 220kV side= 1/0.656 = 1.524

Ratio correction factor calculated internally by relay

to obtain 1 A at 132kV side= 1/0.82 = 1.219

Now, we know the various constrain like CT ratio

error, difference in relaying point due to pilot wire

lengths, magnetizing inrush, percentage Bias is

necessary.

Slope-1 calculation :

IBias = (0.952+1.176)/2= 1.064

Slope 1 = 0.2/1.064= 0.187 (generally set to

0.2 to 0.3)

Slope 2 region comes into scenario with high

through fault current

When I Bias value is much higher. To avoid

mal-tripping in this region we keep

Slope 2 value > 2x slope 1 value. (generally, set to

0.4 to 0.6)

IDiff (High-set)

calculation: - considering 120% margin

of transformer impedance say ZT = 8; 120% of

8 = 9.6


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Harmonic Restrain : We know that transformer

charging current contains different orders of

harmonics, which are not equally suitable for

providing bias. Like, ZERO harmonic (DC or Offset

Component) is unidirectional in nature. Second

harmonic is a typical in wave forms in which

successive half periods do not repeat with reversal

of polarity but mirror image symmetry can be found

about certain ordinates. But we should bear in mind

that normal fault current does not contain second

or other even harmonics and thus ‘2nd harmonic

Blocking’ feature should be automatical ly

withdrawn as soon as the numerical relay detects

a fault during magnetizing inrush.

D. Restricted Earth Fault (REF) Protection:

FOR STAR WINDING : The connection diagram

for REF protection to protect a star-winding is

shown. For a fault occurred out-side protected

zone, the distribution of current shows that there

will be no voltage developed across the relay. The

voltage across the stabil izing resistance at

maximum through fault current is Vs = K*Imax*

(RCT

+ 2*RL

) / n

where :

RCT

= Secondary resistance of CT;

RL = One-way cable resistance from CT secondary

to relaying point; Imax = Maximum external fault

current I

k = stabilizing factor to account the distorted

voltage wave due to fault.

n = CT ratio.

phase opposite direction w.r.t other healthy two

phases resulting zero voltage drop in REF relay.

FOR DELTA WINDING : The connection

diagram for REF protection to protect a Delta-

winding is shown. A fault occurred at out zone;

winding of delta will carry twice current in faulty

REF- Voltage Setting Considerations are as

follows :

Let, VK = CT Knee-point voltage

VS = Stability Voltage Setting V

S <V

R < V

K/2

VR = Relay operating Voltage

If stability voltage increases beyond VK, CT

enters in saturation region for which there is infinite

magnetizing current, but voltage remains at the

same level. This condition is seen open circuited

on the secondary.

VSET

> VS, such that relay will not operate for

external fault.

REF- Stability resistance calculation is as follows :

Let, VK = CT Knee-point voltage; VS = Stability

Voltage Setting; VR = Relay operating Voltage

IR = Relay current setting; IO = magnetizing current

of one CT at VK

m = no. of CT incorporated in the protection scheme;

n = CT ratio

The value of the I Prim = n* { IR + m* (V

S / V

K)* I

O}

The relay current setting IR = (I Prim

/n) – m*

(VS / VK) * I

O

The setting of the stabilizing resistance (RS) =

VS /I

R

E. Circulating Current Protection for auto-

transformer

A circulating current system is arranged between

equal ratio CT in two groups (HV & IV) and the

neutral side. For a 1-∅ bank transformer, we get

three neutrals and we can connect to three separate

relay elements but in case of 3-∅, we get only one

neutral to connect in parallel with all line CT a single

element as shown below.


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Though the protection scheme will not protect

the tertiary winding which is generally a grounded

or an ungrounded delta-winding. For unearthed

delta-winding, Neutral displacement protection may

be appl ied from the tert iary-side vol tage -

transformer. In this protection VT secondary is

connected in open-delta mode. A voltage relay is

energized from the open-delta which measures the

zero-sequence voltage of the line, if any neutral

displacement occurs due to fault. The relay

normally receives zero voltage in healthy

condition but in presence of an earth fault, the

open delta voltages rises from zero to three times

the phase voltage. There are generally two stages

given on neutral displacement relay, the first stage

gives an alarm and the second stage trips both

HV & IV circuit breaker.

For an earthed delta-winding, the earthing is

general ly done by connecting an earthing

transformer to 33kV Bus. A definite Time-delay

earth fault relay may be connected to neutral CT of

earthing transformer to detect a fault on tertiary side

and consequently trip Both HV & IV Circuit breaker.

F. Back-Up Earth-Fault Protection Scheme

For an in-zone earth fault occurred within HV

& LV CT, i t wi l l be detected by Differential

protection but if an earth fault occurs beyond

the said region at any point of 33kV system or

one feeder circuit breaker pole not opened for a

33 kV feeder fault. It will be detected by the

back-Up earth fault relay connected to the

earthing transformer neutral CT. The relay

generates trip to each HV side circuit breakers

o f more than one t rans fo rmer those a re

connected to the faulty 33kV Bus.


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Magnetizing current test at Low Voltage of

transformer :

This test is performed to locate defects in the

magnetic core structure, shifting of windings.

Failures in between turn insulation or problem in

tap changers. These condit ions change the

effective reluctance of the magnetic circuit, thus

affecting the current required to establish Flux in

the core.

1. At first isolate the neutral grounding path from

transformer.

2. Keep the transformer Tap Changer in a Lower

tap, Normal Tap and Maximum tap position

respectively. Test should be done on above

respective taps.

3. Then apply three phase 415 V supply on the

line terminals for three-phase transformers.

4. Measure the supply voltage and current in each

phase.

5. Now measure the magnetizing current of

transformer with keeping tap changer in normal

position.

6. Lastly repeat the test with keeping the tap at

Lower and Highest position.

Normally, there are two similar higher readings

on two outer limb phases on transformer core and

one lower reading on the centre limb phase, in the

case of three phase transformers. An agreement

to within 30% of the measured exciting current with

TESTING AFTER ASSEMBLY OF THE

TRANSFORMER AT SITE

ER. SANJIT CHAKRABORTY, DE(E)

Midnapore Testing Area Office, WBSETCL

the previous test is usually considered satisfactory.

If the measured exciting current value is 50 times

higher than the value measured during factory test,

there is a likelihood of a fault in the winding which

needs further analysis.

Caution : This magnetizing current test of

transformer is to be carried out before DC

resistance measurement. This test should be

done before measurements of winding

resistance to reduce the effect of residual

magnetism. Magnetizing current readings may

be effected by residual magnetism in the core.

Therefore, transformer under test may be

demagnet ized before commencement of

magnetizing current test.

Transformer Magnetic Balance Test Procedures:

1. At first isolate the neutral grounding path from

transformer.

2. Keep the transformer Tap Changer in a Lower

tap, Normal Tap and Maximum tap position

respectively. Test should be done on above

respective taps.

3. Apply a single-phase AC voltage (230-250

Volts) on one of the terminals of the HV

winding.

5. Measure the voltage between the two other HV

terminals.

6. Repeat the test for each of the three phases.

Left side phase Central phase Right side phase

AN BN CN

Voltage applied at left side phase 100% 60-90 % 10-40 %

Voltage applied at central phase 50% 100% 50%

Voltage applied at right side phase 10-40% 60-90% 100%


A B

C D

Based on the results shown in the table above,

if the voltage applied at one side is equal the sum

of the voltages obtained at the two other sides, this

indicates that the transformer is magnetically

balanced. But if there is any short circuit between

turns, the sum of the two voltages may not be equal

to the applied voltage.

The results shown in the table indicate that the

Magnetic balance test is only an indicative test for

the transformer. The results obtained by the

distribution of the voltage in the core of the

transformer are not absolute; therefore, this test

should be used in conjunction with other tests to

give more effective results.

Transformer Turns-Ratio (TTR) Test

The transformer turns-ratio (TTR) test is a

functional check of the transformer used to assess

if it is properly transforming voltage, according to

the nameplate value. The TTR test is one of the

most important diagnostic tests for a power

transformer. If the TTR test does not “pass”, then

the transformer is usually not put to service until

the source of the issue has been identified and

resolved. The TTR test is performed by applying

an AC (50Hz) 12Volt or 120 Volt across HV winding

of the transformer, while the induced voltage across

a secondary winding is measured. The transformer

turns-ratio is calculated by dividing the voltage

applied across the primary winding by the voltage

measured across the secondary winding.

The TTR measurement is used to detect the

following transformer failure modes,

n Compromised Insulation (turn-to-turn, inter-

winding, and/or winding-to-ground insulation)

n Core Defects

n Tap-Changer Component Faults (e.g. faults

involving the preventative autotransformer,

regulating winding, reversing switch, tap

selectors, stationary contacts, etc.)

n Severe Discontinuities, Poor Connections, and/

or Open-Circuits

n Severe Mechanical Failures (e.g. winding

movement or deformation)

According to the IEEE C57.152 guidelines, the

measured turns-ratio of a transformer should

compare to within ±0.5% from the nameplate value.

However, what is just as important for the TTR test

analysis is that the ratio deviation percentage

(relative to the nameplate value) for all three

phases is approximately equal. However, when

performing investigative tests, the applied voltage

during the turn’s ratio measurement should be as

high as possible. This provides the user with the

best chance to detect a fault within the transformer.

A “low-voltage (12 Volt)” TTR instrument may not

detect a voltage sensitive failure (e.g. a voltage

sensitive turn-to-turn insulation failure) within the

transformer. Therefore, for fault investigations, it

is recommended that higher voltage (120 Volt) TTR

test is performed to apply a higher electrical stress

to the insulation system.

Transformer winding resistance Test

Winding resistance measurements are an

important diagnostic tool for assessing possible

damage to transformers resulting from poor design,

assembly, handling, unfavourable environments,

overloading or poor maintenance.

The main purpose of this test is to check for

gross differences between windings and for opens

in the connections. Measuring the resistance of

transformer windings assures that each circuit is

wired properly and that all connections are tight.

Winding resistance in transformers will change

due to shorted turns, loose connections, or

deteriorating contacts in tap changers. Regardless

of the configuration, the resistance measurements

are normally made phase-to-phase and the

readings are compared with each other to

determine if they are acceptable.

Transformer winding resistance measurements

are obtained by passing a known DC current

through the winding under test and measuring the

voltage drop across each terminal (Ohm’s Law).

Modern test equipment for these purposes utilizes

a Kelvin bridge to achieve results; you might think

of a winding resistance test set as a very low-

resistance ohmmeter.

Sweep Frequency Response Analysis

Sweep frequency response analysis (SFRA) is

a method to evaluate the mechanical integrity

o f core , w ind ings and c lamping s t ruc tures

within power transformers by measuring

their electr ical t ransfer funct ions over a

wide frequency range.


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C D

SFRA is a comparative method, meaning an

evaluation of the transformer condition is done by

comparing an actual set of SFRA results to

reference results. Three methods are commonly

used to assess the measured traces:

l Time-based – current SFRA results will be

compared to previous results of the same unit.

l Type-based – SFRA of one transformer will be

compared to an equal type of transformer.

l Phase comparison – SFRA results of one

phase will be compared to the results of the

other phases of the same transformer.

Transformers generate a unique signature when

tested at discrete frequencies and plotted as a

curve. The distance between conductors of the

transformer forms a capacitance. Any movement

of the conductors or windings will change this

capacitance. This capacitance being a part of

complex L (inductance), R (Resistance) and C

(Capacitance) network, any change in this

capacitance will be reflected in the curve or

signature.

An initial SFRA test is carried out to obtain the

signature of the transformer frequency response

by injecting various discreet frequencies. This

reference is then used for future comparisons. A

change in winding position, degradation in the

insulation, etc. will result in change in capacitance

or inductance thereby affecting the measured

curves.

Tests are carried out periodically or during major

external events like short circuits and results

compared against the initial signature to test for

any problems.

SFRA analysis can detect problems in

transformers such as :

Three-Phase Transformer Delta Winding Resistance Test Connections

Three-Phase Transformer Wye-Winding Resistance Test Connections


A B

C D

l winding deformation – axial & radial, like hoop

buckling, tilting, spiralling

l displacements between high and low voltage

windings

l partial winding collapse

l shorted or open turns

l faulty grounding of core or screens

l core movement

l broken clamping structures

l problematic internal connections

Insulation Resistance test of transformer

Steps for measuring the IR of Transformer :

l Shut down the transformer and disconnect the

jumpers and lightning arrestors.

l Discharge the winding capacitance.

l Thoroughly clean all bushings

l Short circuit the windings.

l Guard the terminals to eliminate surface

leakage over terminal bushings.

l Record the temperature.

l Connect the test leads (avoid joints).

l Apply the test voltage and note the reading.

The IR. Value at 60 seconds after application

of the test voltage is referred to as the

Insulation Resistance of the transformer at the

test temperature.

l The transformer Neutral bushing is to be

disconnected from earth during the test.

l All LV surge diverter earth connections are to

be disconnected during the test.

l Due to the induct ive character ist ics of

transformers, the insulation resistance reading

shall not be taken unti l the test current

stabilizes.

l Avoid meggering when the transformer is under

vacuum.

1. Megger connects to LV and HV bushing studs

to calculate the importance of IR insulation

resistance between LV and HV windings.

2. Megger leads to connecting to HV bushing

studs and earth point transformer tanks to

calculate the importance of IR insulation

resistance between HV windings and earth.

3. Megger leads to the relation between the LV

bushing studs and the transformer tank earth

point to calculate the strength of IR insulation

resistance between the LV windings and

ground.

The Polarisation index test measures the ability

of the insulation to absorb voltage over a period of

time. This gives an indication of the over all

insulation quality of the individual pieces of

insulation in the transformer. This test is usually

performed in conjunction with the Megger Test. It

is measured as ratio of insulation resistance (IR)

for 10 minutes to insulation resistance for 1 minute.

Factors affecting on IR value of Transformer

The IR value of transformers are influenced by

l Surface condition of the terminal bushing

l Quality of oil

l Quality of winding insulation

l Temperature of oil

l Duration of application and value of test voltage

Transformer Stability Test Procedure :

The Purpose of Stability test is to determine the

Healthiness of the CT circuits which is protecting

the in winding from actual fault conditions and

through fault conditions.

Principle of Differential Protection scheme and

Testing :

The scheme is applied for protecting the

transformer from fault in the winding and to avoid

spurious operation of scheme due to outside zone

faults. This Differential Testing mainly carried out

to ensure the correctness of CT selection and

setting parameters during fault sensing. The

Differential relay monitors the primary & secondary

side CT currents magnitude and vectors and

operates for the in zone fault conditions, restrains

for the through fault conditions.

VERIFICATION OF DIFFERENTIALSTABILITY :

To verify the Differential CT circuits the following

test / methods are adopted,

1. First of all the current generated during the

Differential stability test is calculated using the

% z voltage and source to feed the current will

have to be chosen.


A B

C D

2. Apply the 440 VAC supply from LV side of the

Transformer in such way that HV and LV CT’s

are included in the circuit.

3. Shorted the 3 phase of the Transformer HV side

and earthed (include HV CT’s) with sufficient

current carrying cable after the HV side CT’s.

So the Differential relay will see the load / fault

currents.

4. Differential Relay has to be set as per the

required calculated setting values before

starting the stabil ity test. (i.e.: CT Ratio

correction factor, Vector Correction factor)

5. Now the secondary currents of Primary &

secondary CT’s, Bias currents, Relay currents,

Restrain currents, Operate currents can be

noted down from the Different ial Relay

measuring menu. At the stability condition the

Primary & secondary currents magnitude and

vector should match. No current should pass

through the operating coil of the relay.

TRANSFORMER REF STABILITY TEST

Objective :

The Purpose of REF Stability test is to determine

the Healthiness of the REF CT circuits which is

protecting the transformer in Zone area from actual

fault conditions and through fault conditions.

Principle of Protection :

This scheme is appl ied to protect the

transformer from the In Zone Earth faults. REF

Protection provides an extremely fast, sensitive and

stable method of detecting winding earth faults.

REF must remain stable under switching and

through fault conditions (out-side of CT’s). This is

achieved with by including stabilizing resistor in

series with REF current measuring input.

VERIFICATION OF REF STABILITY :

In case of outdoor CT’s




2. Out zone fault test :

Only one phase (R or Y or B) of HV side should

earthed including HV CT is called “out zone

fault”. Current should be measured NCT (in

case of HV (STAR) side) secondary as well as

secondary side of outdoor CT’s. During stable

condition no current flow in REF relay coil.

In zone fault test


earthed excluding HV CT’s is called “In zone fault”,

as result fault current flowing in REF relay coil and

REF relay will be operate.


A B

C D

In case of Bushing CT’s




2. A. Out zone fault test :


earthed including HV CT is called “Out Zone

fault”. Current should be measured NCT (in

case of HV (STAR) side) secondary as well as

secondary side of outdoor CT’s. During stable

condition no current flow in REF relay coil.

Relay will not be operated.

B. In zone fault test

If we change the polarity of secondary side of NCT,

the fault current will be flow in the REF relay coil is

called “In zone fault”, so REF relay will be operate.

N.B After completing the in zone test the

connection should be retained in previous Position

and again check REF Stability (no current flow in

REF relay coil).


A B

C D

Critical statutory function of SLDC : The

Electricity Act 2003 mandates that the Load

Despatch Centre shall schedule in accordance with

the contracts and keep account of electricity

transmitted through the transmission grid. This

implies that a ‘ledger’ of energy transactions have

to be maintained, the physical flow of electricity

across various notional seams in the electricity grid

have to be measured and ‘energy balance sheets’

have to be prepared at the transmission level. The

measurements have to be at the remote

substations and collected at a centralized location

for preparation of ‘energy statements’ that indicate

the scheduled and actual interchange of entities

with the grid as well as account for the transmission

losses incurred in the grid. The transaction would

have to be scheduled, physical delivery would have

to be measured, accounted for and finally settled

across multiple seams. The financial settlement of

all the energy transactions wouldultimately require

scheduling and book keeping besides a tamper-

proof, robust, scalable,flexible and dispute-free

energy metering, accounting and settlement

system. The invoice for the charges related to

capacity, active energy, incentive, reactive energy,

transmission usage, deviation from schedule,

market operation, trading margin that have to be

raised by power sector utilities rely on the energy

account statements. The integrity, probity and

timeliness of the energy accounting and settlement

system are indispensable for the viability, financial

stability and sustainability of the sector. Thus, it is

essential that the adequate priority and importance

is assigned to this critical statutory function of

SLDC.

Required steps : Activities of Scheduling,

Accounting, Metering and Settlement are highly

SCHEDULING, ACCOUNTING, METERING AND

SETTLEMENT OF POWER BY SLDC ACCORDING

TO THE REPORT OF FORUM OF REGULATORS

(FOR) ON SAMAST PUBLISHED IN JULY’2016

ER. AMITAVA NAG, ACE

RAC, WBSETCL

data intensive and complex. Deployment of

Information Technology (IT) applications to

automate, streamline and integrate. The entire

gamut of activities is strongly recommended.

Automatic Meter Reading System needs to be in

place for cutting down the time taken in meter data

collection. Web-based interface is required for

activities such as open access request processing,

scheduling, reporting and billing. In an evolving and

growing electricity market of India, long-term

sustainability of IT logistics at the SLDC requires

long-term collaboration with IT service providers

to develop and deliver customized IT solutions.

From the “Report on India’s Renewable

Electricity Roadmap of 2030" of NitiAayog :

Currently, in India, scheduling occurs on a day-

ahead basis while dispatch occurs on a 15-minute

basis. System operations technologies and

protocols need to be updated to enable five-minute

scheduling and dispatch of all resources connected

to the grid and automated incorporation of RE

forecasts. It should be noted that accuracy of RE

forecasts is significantly higher the closer they get

to dispatch. Consequently, the ancillary service

requirements will also be lower.

From Draft Energy Policy (2017) of Niti Aayog :

System operations technologies and protocols will

be updated to enable five-minute scheduling and

dispatch ( this wi l l lower anci l lary service

requirements) [Ref: Renewable Energy Grid

Integration and Efficient Grid Operation Strategies]

5-minute scheduling and settlement : FOR

Technical Committee appreciated the need to move

to 5-minute scheduling and settlement and formed

a Sub-Group to examine the issue. The Sub-Group

in its meetings decided as below :


A B

C D

l All RPCs may discuss the 5-minute scheduling

and settlement

l NPC to follow up the status of amendment of

metering standards with CEA and also place

the required amendments as agenda item in

the next NPC meeting.

l CTU to facilitate collection of the region-wise

data on type, vintage and location of existing

meters along with proposed procurement

process.

l Need for capacity building for better forecasting

and scheduling - SLDCs to coordinate with

RLDCs/NLDC. Interactive sessions may be

organized at different RPCs for generation of

ideas and solutions.

l In view of SAMAST implementation, the states

who are about to implement the intrastate

accounting and settlement system could

leapfrog and go for scheduling and settlement

at 5-min interval. ERPC has decided in

commercial committee meeting that it shall

keep an agenda for 5-minute scheduling and

settlement in TCC meeting.

Information Technology (IT) Logistics :

Market Operation function can no longer succeed

with fragmented and standalone IT systems. Each

process has multiple inputs and interface with

internal as wel l as external systems. Thus

standardization, scalability and flexibility are

essential. Several activities such as scheduling and

open access processing require web-based

interface for faci l i tat ing simultaneous and

continuous coordination with multiple Users /

stakeholders. Such activities require web-based

interface for convenience of internal as well as

external stakeholders. The software applications

need to be continuously aligned with the evolving

regulations and evolving requirement of the

stakeholders and Users of the applications.

Automatic Meter Reading : The Automated

Meter Reading System along with the necessary

communication infrastructure is necessary for

preparing deviation accounts on weekly basis.

Possible model of Software Applications :

Development of software applications to be through

collaboration of in house team and a long term IT

partner so as to be adapt the systems to the

regulatory directions and amendments. Web-based

interface to be deployed wherever feasible (e.g.

scheduling Open Access request processing, User

Registrat ion etc.) . Energy Account ing and

settlement system to be made paperless with the

help of IT tools. Repetitive and tedious activities

to be automated. Automatic Meter Reading System

to be in place with adequate communication

system. Telemetry of Meter data is desirable for

faster accounting. The maintenance of IT hardware

could be outsourced.

Development in respect of WBSETCL :

i) WBSETCL has sought Rs. 25.96 Cr grant from

PSDF for implementation of integrated system

for Scheduling, Accounting, Metering and

Settlement of Transactions (SAMAST) system

in West Bengal which is yet to be sanctioned.

ii) Rs. 31.19 Cr Grant from Power System

Development Fund (PSDF)is sanctioned

towards mitigating 50% of the cost of project

for establishment of Reliable Communication

and Data Acquisition at different substation at

the state of West Bengal.

Development in other parts of India :

Some SLDCs have made significant progress in

SAMAST implementation, involving the placement of

orders for procuring software and meters and their

subsequent deployment, which account for a major

part of the DPR amount. The Rajasthan SLDC had

completed major portion of the work. Its DPR was

approved by the PSDF committee in May 2017. Eight

other states/UTs that have initiated SAMAST

implementation are Chhattisgarh, Delhi, Gujarat,

Kerala, Madhya Pradesh, Maharashtra, Odisha and

Tamil Nadu. Of these, only Madhya Pradesh and

Tamil Nadu approached the PSDF for financial

assistance while six others have started

implementation without that grant.

Role of USAID : USAID (India) is funding a five-

year project to help India meet its ambitious RE

targets. This project, known as Greening the Grid

(GTG), is assisting the Government of India (GOI)

in integrating large-scale, variable renewable

energy (VRE) into the existing power grid. Critical

to it is rigorous analytical support to identify grid

stability issues, options for optimizing despatch,

and sources of potential flexibility. Pilot projects

are at the core of the GTG Program.


A B

C D

These projects are multi-implementer work

programs aimed at testing and evaluating building

blocks to improve RE integration into India’s state

and national power grids. USAID/India’s GTG

project combines three components, which interact

with each other. These are:

l Power system planning reforms and targeted

analysis for large RE parks and RE integration

pilots implemented by U.S. Department of

Energy (DOE) Laboratories.

l Renewable Integration and Sustainable Energy

(RISE) initiative to implement innovation pilots,

aimed at testing and evaluating building blocks

to improve the integration of RE; and

l Peer-to-peer exchanges between U.S.-India

system operators (System Operator Partnership)

and regulators (India Regulatory Partnership).

In states like Punjab, Himachal Pradesh and

Haryana, the GTG-RISE team is assisting SLDCs for

preparation of DPR for SAMAST implementation.


A B

C D


A B

C D



A B

C D


^

S. N. ELECTRICALS(Govt. Licence Contractor & General Order Suppliers)

Enlistment to W.B.S.E.D.C.L. & Other concern

Regd. Office :

Vill. + P.O. Chakur, P.S. BagnanDist. Howrah, Pin - 711 303

Branch Office :

Bagnan Bus Stand‘TRENDZ SPOT’ Building, Ground Floor

Phone : (03214) 270269, Mobile : 94343 01138, 96474 78989E-mail : [email protected]


A B

C D


_

M/S. ADHIKARI & SINHA

Govt. Licenced Electrical, Civil Contractor &


Enlisted with WBSEDCL

252, Pakuria, P.O. ChaltiaBerhampore, Murshidabad


C.L. No. 105304, P.F. Code - JL/JNG/0038750ESIC IP No. 74000628930001019GSTIN No. 19AAKFA3056C1ZP

PAN No. AAKFA3056CVendor Code No. 508613


_

M/s. H. B. ConstrM/s. H. B. ConstrM/s. H. B. ConstrM/s. H. B. ConstrM/s. H. B. Constructionuctionuctionuctionuction

ELECTRICAL CONTRACTOR & GENERAL ORDER SUPPLIER

Enlisted : W.B.S.E.D.C.L.

C/o. Jitendra Nath Saha, B. S. Road (Churi Patti)P.O. & Dist. Malda

Mobile : 94743 45277

Prop. : BIPLAB KUMAR SAHA


A B

C D


]

M/S. INDUSTRIAL ENTERPRISEM/S. INDUSTRIAL ENTERPRISEM/S. INDUSTRIAL ENTERPRISEM/S. INDUSTRIAL ENTERPRISEM/S. INDUSTRIAL ENTERPRISE

L. No. 10283 (Govt. of W.B.)

Enlisted Electrical Contractor WBSEDCL / WBSETCL (Authorised)

Kishore Nagar (Near Water Tank)Contai, Purba Medinipur

Contact No. 89001 56022E-mail : [email protected]


A B

C D


^

M/S. JANA ENTERPRISE

Govt. Conractor (Civil, Electrical) and


Regd. Office :

At. Purunda, P.O. NeguaDist. Purba Medinipur, Pin - 721 448Mobile : 94740 85045, 97336 50010E-mail : [email protected]

Registered No. : 7607

PAN Card No. : ACRPJ0074G, GST No. : 19ACRPJ0074G2ZF

PF Code No. : JH / JP / 14557, ESIC No. : 41000666630001019


A B

C D


@

MOONLIGHT ELECTRICALS

ELECTRICAL ENGINEERS & GOVT. LICENCE CONTRACTOR

Enlisted by West Bengal State Electricity Distribution Co. Ltd.

Residence :Vill. & P.O. Wadipur, P.S. Domjur

Dist. Howrah - 711 411

Mobile : 98307 10640


A B

C D


_

M/s. Purnima Electrical Enterprise

GOVT. LICENCE, ELECTRICAL CONTRACTOR

Electrical Engineers & General Order Suppliers

Enlisted by W.B.S.E.D.C.L. (Electrical)

Vill. & P.O. Joynagar (Near Jogmaya Ashram)P.S. Panchla, Dist. Howrah - 711 302 (W.B.)

Phone : 2661 6123, Mobile : 94336 91970

GSTIN : 19AAQFP5352A1Z5


A B

C D


F

M/S. UNIQUE CONSTRUCTION

Govt. Electrical Licensed Contractor & General Order Suppliers

Enlisted in W.B.S.E.D.C.L.

C. L. No. 10798

Office :

ASOKE KR. SEN

Kushalay Apartment, Subhaspally, Jhaljhalia, Malda

Mobile : 94346 80491


A B

C D


_

S. G. ENTERPRISES. G. ENTERPRISES. G. ENTERPRISES. G. ENTERPRISES. G. ENTERPRISEGovt. Enlisted Contractor & General Order Supplier

Subhash Pally, P.O. JhaljhaliaDist. Malda, Pin - 732 102 (W.B.)


q


A B

C D


_

M/s. M/s. M/s. M/s. M/s. BISWAS ENTERPRISEBISWAS ENTERPRISEBISWAS ENTERPRISEBISWAS ENTERPRISEBISWAS ENTERPRISE

Head Office :

‘Genexx Valley’, Building No. 26, Flat No. 5FDiamond Harbour Road, Joka Metro Station

Kolkata - 700 104 (Paschimbanga)

Site : Office :

Qtr. No. A/49, N.T.P.C. Ltd. Farakka, P.O. NabarunPin - 742 236, Dist. Murshidabad (Paschimbanga)

Tel. : +91 94340 44684, +91 89004 59986, +91 94340 44699E-mail : [email protected]

[email protected]


A B

C D


^

STATE ELECTRIC CO.GOVT. LICENSED CONTRACTOR (ELECTRICAL)

Head Office :

Nabghara Amta Road Jn., N.H.-6, Howrah - 711 322Phone : (033) 2661 6873, Fax : (033) 2661 6873

Corporate Office :

2, Corporation Place, Kolkata - 700 087Phone : (033) 2227 7280, Fax : (033) 2227 6903

Branch Office :

Ankur Hati, Near Mohiary No. 2 GP, Howrah - 711 409Tele Fax : (033) 2669 4722

SEC


A B

C D


-

SIGMAENLISTED CONTRACTOR

WBSEB & P.W.D. (Elec.) & General Order Suppliers

C.L. No. 4619

Office at :

SUBRATA KUNDUChanditala, P.O. Raiganj, Dist. Uttar Dinajpur

Mobile : 94343 84212

Branch :

C/o. LATE SIB SANKAR KUNDUTandelpara, P.O. Chanchal, Dist. Malda

Σ


A B

C D


_

M/s. Gourangaprabhu SarkarGOVT. CONTRACTOR

Specialist in : Civil Eng., Elect., Eng. Supply and Transport

Postal Address :

Maheshmati, Malda - 732 101

Mobile :94345 10839, 89670 23485 (Niladri Sarkar)

94349 81189, 81590 23126 (Himadri Sarkar)



A B

C D


@

RABINDRA NATH MAITY

ELECTRICAL CONTRACTOR & COURIER SERVICE

Nandakumar, Purba MedinipurPin - 721 632, West Bengal

Mobile : 94349 40376

Enlisted in :

W.B.S.E.D.C.L.

Vendor Code No. : 505397

GSTIN : 19ANWPM2602D1ZX


A B

C D


+

M/S. A. K. DAS & CO.Consulting Engineers & Erectors

Govt. Licensed Electrical Contractor & General Order Suppliers

Govt. Licensed No. 10571, Enlisted by W.B.S.E.D.C. Ltd.

Specialists in : Electrical Erection & Maintenance Works

Office :

Chakjia Dighi, NandakumarPurba Medinipur, Pin - 721 649, W.B.

Site : Office :

Deulpota, ChaitanyapurHaldia, Purba Medinipur

Mobile : 94342 36379, 81670 98345


A B

C D


]

M/S. JOY MAA TARA ENTERPRISE

W.B.S.E.D.C.L. Enlisted Contractor & General Order Suppliers

Vill. Bahargram, P.O. Panskura (R.S.)P.S. Panskura, Dist. Purba Medinipur

Pin - 721 152



A B

C D


_

M/s. RABINDRA NATH BERA

Enlistment Electrical Contractor of W.B.S.E.D.C.L. & General Suppliers

At.- Aklabad (Ward No. 09) P.O. EgraDist. Purba Medinipur, Pin - 721 429


Prop. : RABINDRA NATH BERA


A B

C D


^

Shiva Engineering WorksShiva Engineering WorksShiva Engineering WorksShiva Engineering WorksShiva Engineering Works

MECHANICAL ENGINEERS & GENERAL ORDER SUPPLIERS

58/8, Naskarpara Lane, Kasundia, Howrah - 711 101



A B

C D


A B

C D


^

BAG ELECTRICAL ENTERPRISEELECTRICAL ENGINEER GOVT. LICENCE CONTRACTOR & GENERAL ORDER SUPPLIERS

ENLISTED BY WBSEDCL, WBSETCL & OTHER CONCERN

Office :

Vill. & P.O. Deulpur, Via - Begri, P.S. PanchlaDist. Howrah, Pin - 711 411



A B

C D


]

ELECTRO MECH

GOVT. CONTRACTORS

ELECTRICAL, ELECTRONICS & MECHANICAL ENGINEERS

Ramrajatala Station Road (West)P.O. G.I.P.C., Howrah - 711 112

Phone : 2657 3199


F

THE MARKET ELECTRICAL

ENGINEERING WORKS

GOVT. LICENSED CONTRACTOR (ELECTRICAL)

Head Office :

Nabghara Amta Road Jn., N.H.-6, Howrah - 711 322Phone : (033) 2661 6873, Fax : (033) 2661 6873

Corporate Office :

2, Corporation Place, Kolkata - 700 087Phone : (033) 2227 7280, Fax : (033) 2227 6903

Branch Office :

Ankur Hati, Near Mohiary No. 2 GP, Howrah - 711 409Tele Fax : (033) 2669 4722

MEEW


A B

C D


F

M/s. P. K. SINHAEnlisted with WBSEDCL & Working Contractor of Govt. Dept.

GOVT. LICENCED ELECTRICAL CONTRACTOR (L. NO. 3333)

ELECTRICAL GOODS & GENERAL ORDER SUPPLIER

Specialists in :

Electrical O.H. Erection Works, Internal Wiring Installations &

Illumination Works

Head Office :

Town Padumbasan, TamlukPurba Medinipur, Pin - 721 636 (W.B.)


GSTIN : 19AADFP5531G129


A B

C D


]

APEX INDUSTRIESGovt. Contractor & General Order Suppliers

Regd. Office

Padumbasan (W.O No. 5), TamlukPurba Medinipur, Pin - 721 636



A B

C D


_

M/s. PAUL & CO.Govt. Enlisted Electrical Contractor & General Order Supplier

(W.B.S.E.D.C.L.)

Residence :

Vill. Sayadpur (Ward No. 2), P.O. & P.S. TamlukDist. Purba Medinipur, Pin - 721 636

Office :

Parbatipur, TamlukPurba Medinipur, Pin - 721 636



A B

C D


]

M/S. UTTAM ENTERPRISE

Govt. Contractor of erection HT, LT & Maintenance

and Transformer Repairing Workshop

Enlisted WBSEDCL

Regd. Head Office :

Telami, Benachakri, EgraPurba Medinipur, Pin - 721 429

Mobile : 99336 89916

Branch Office :Kudi, Rasan, Egra

Purba Medinipur, Pin - 721 429Mobile : 99333 97831

Reparing Workshop :

Krishnapur, P.O. & P.S. BeldaPaschim Medinipur, Pin - 721 424

Mobile : 98367 71835


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C D


-

H. S. J. ConcreteH. S. J. ConcreteH. S. J. ConcreteH. S. J. ConcreteH. S. J. Concrete

IndustriesIndustriesIndustriesIndustriesIndustriesApproved P.C.C Pole Manufacturer of WBSEDCL (S.S.I. Unit)

P.O. Barua (Beldanga), MurshidabadPin - 742 189 (W.B.)



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@

NOBLE CONSTRUCTION CO.NOBLE CONSTRUCTION CO.NOBLE CONSTRUCTION CO.NOBLE CONSTRUCTION CO.NOBLE CONSTRUCTION CO.

CONTRACTORS, BUILDERS AND P.C.C POLE MANUFACTURERS (S.S.I. UNIT)

P.O. Barua (Beldanga), MurshidabadPin - 742 189, (W.B.)

Phone : (03482) 264159 (Off.)Mobile : 94340 09664, 94342 02988, 99323 15787



A B

C D


_

MAHAVIR UDYOGManufacturer of PCC Pole and General Order Suppliers

Enlisted with W.B.S.E.D.C.L.

Ghuni, P.O. Muktinagar, P.S. BerhamporeMurshidabad, Pin - 742 102, (W.B.)

Mobile : 09330271776E-mail : [email protected]

GST IN : 19AAQFM5212J1ZYState : West Bengal, State Code : 19


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M/s. SHREE GURU ENTERPRISE

Enlisted Electrical Contractor of W.B.S.E.D.C.L. and

General Suppliers

Vender Code : 506440

Vill. & P.O. Amarpur, P.S. PatashpurDist. Purba Medinipur, Pin - 721 439



A B

C D


]

M/s. Indradeep Enterprise

Govt. Licenced Electrical Contractor, Fabricators & General Order Supplier

Enlisted with W.B.S.E.D.C.L., P.W.D. and Civil WorksContractor Licence (Electrical) No. 13946

Registered Office :

Vill. Talbaganpara, P.O. & P.S. BerhamporeDist. Murshidabad, Pin - 742 101 (W.B.)


Enlistment No. RE/Enlistment/PROV/F-10/220/95

PAN - AAEFI6899M, GST IN : 19AAEFI6899M2ZC

P.F. Code No. WB/JNG/45174, E.S.I. No. 74000628530001019

Vendor Code : 508631


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_

DHAR CONSTRUCTIONGOVT. CONTRACTOR & GENERAL ORDER SUPPLIER

Enlisted in WBSETCL & WBSEDCL

4, Manindranagar, P.O. Cossimbazar RajDist. Murshidabad, Pin - 742 102, (W.B.)

E.P.F Registration No. WB/38755

ESIC Registration No. 74000636560001001

GST IN Registration No. 19AACFD0180AIZ3

Professional Tax Code No. 192009518194


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M/s. B. M. INDUSTRIESGovt. Licenced Electrical Contractor & General Order Supplier

Enlisted with W.B.S.E.D.C.L., P.W.D. and Civil Works

Registered Office :

Vill. + P.O. + P.S. Raninagar, Dist. MurshidabadPin - 742 308, West Bengal


L.C. No. 12192, Enlistment No. R/2016/20/434

P.F. Code No. WB/JNG/45033, Vender Code : 508917

PAN No. AANFB8467F, GSTIN : 19AANFB8467F2ZX

E.S.I.C. No. 74000628480001019


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M/s. JOYDEV JANAGOVT. CONTRACTOR & GENERAL ORDER SUPPLIER

Enlisted Civil Contractor - W.B.S.E.D.C. Ltd., Midnapur Zone

Office :

Ratnali, Radhaballavpur, TamlukPurba Medinipur, Pin - 721 627


P.F. Code No. WB/CA/40145

Vat Registration No. 19851373011

PAN No. ACFPJ4419B

Service Tax Registration No. ACFPJ4419BSD001


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_

Bhunia EnterpriseBhunia EnterpriseBhunia EnterpriseBhunia EnterpriseBhunia Enterprise

Govt. Licensed Electrical Contractor & General Order Suppliers


Head Office :

Vill. Alipur, P.O. Boba, P.S. KhejuriDist. Purba Medinipur, Pin - 721 431

Branch Office :

Vill. Sarada, P.O. Sarada, P.S. ContaiDist. Purba Medinipur, Pin - 721 427

Mobile : 99333 65772, 94340 23234, 97345 92921, 947567140, 94756 73140E-mail : [email protected]


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S. E. ConstructionGOVERNMENT CONTRACTOR

Civil, Mechanical & Electrical Contractor

Earth Movers Equipments & Materials Supplier

Grit Blasting, Sand Blasting & Industrial Painting

Regd. Office :

Shrikrishnapur, RaghurampurSutahata, Haldia, Dist. Purba Medinipur

Pin - 721 645, W.B.


[email protected]


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F

THE MARKET ELECTRICAL

ENGINEERING WORKS

GOVT. LICENSED CONTRACTOR (ELECTRICAL)

Nabghara Amta Road Jn., N.H.-6, Howrah - 711 322

Phone : 2661 6873, Fax : (033) 2661 7863E-mail : [email protected]

MEEW


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F

M/s. ZAMAN ELECTRICALS CO.Govt. Licenced Electrical Contractor & General Order Supplier

Enlisted with W.B.S.E.D.C.L

Licence No. 16660, Vender Code : 512408

Vill. + P.O. Bhabta, P.S. Beldanga, Dist. Murshidabad, Pin - 742 134Mobile : 86299 48155, 75012 19319


VAT - 19761331597, PAN No. AABFZ2866Q

GST No. 19AABFZ2866QIZ8, Service Tax No. AABFZ2866QSD001


F

STP ELECTRO ENGINEERSRepairer of Distribution & Power Transformer, Vacuum-cum-Hot Filteration

of Power transformer & General Order Supplier

Enlisted with W.B.S.E.D.C.L, W.B.P.D.C.L, B.H.E.L, A.B.B Ltd. & I.P.C.L.

Office & Work Shop :

Paschimgamini, P.O. Balarampur, Dist. Murshidabad, Pin - 742 165Mobile : 94346 42457, 94752 28556


PAN No. AARFS4306E, GST No. 19AARFS4306E1Z1


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EASTERN ELECTRICALS

GOVT. LICENSED ELECTRICAL CONTRACTOR & GENERAL ORDER SUPPLIERS

Office :

Vill. Chandrapur, P.O. Bagnan, Dist. Howrah



NATIONAL ELECTRICENLISTED BY : W.B.S.E.D.C.L. & OTHER CONCERN

Electrical Engineers & Govt. Licensed Contractors & General Order suppliers

Head Office :

Vill. + P.O. Nabagram SikipurDist. Howrah, Pin - 711 315

Branch Office :

Bazarpara, Uluberia, HowrahBakultala, Howrah


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M/s. B. S. ENTERPRISE

Govt. Electrical Contractors &



Business Office :Vill. Dwarikapur, P.O. Totanala

P.S. Bhagwanpur, Dist. Purba MedinipurMobile : 97326 19083

Head Office :14/A, Parui Das Para Road

(Shyamsundar Palli), Kolkata - 700 061Mobile : 94337 69947


G

ARYA ELECTRICALSGovt. Enlisted Electrical Contractor &


Parbatipur, Tamluk, Purba Medinipur

Mobile : 94344 17737, 80018 69106


BHARAT ENGINEERING

SYNDICATE

GOVT. LICENSED ELECTRICAL CONTRACTOR &

GENERAL ORDER SUPPLIERS

Enlisted W.B.S.E.D.C.L. & Other Concern

Office :Vill. Majherati (Panpore More) P.O. Jadurberia

P.S. Uluberia, Howrah - 711 316



G

BALITIKURI ELECTRICAL

GOVT. LICENCE ELECTRICAL CONTRACTORS

Enlisted Erection Contractors underW.B.S.E.D.C.L.

All types of Electrical Machinery Repair &


Balitikuri, Chakpara, Howrah - 711 113Mobile : 98360 07492


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F

Bhunia EnterpriseGovt. Licensed Electrical Contractor &



Head Office :Vill. Alipur, P.O. Boba, P.S. Khejuri

Dist. Purba Medinipur, Pin - 721 431

Branch Office :Vill. Sarada, P.O. Sarada, P.S. ContaiDist. Purba Medinipur, Pin - 721 427

Mobile : 99333 65772, 94340 23234,97345 92921, 947567140, 94756 73140



F

M/s. S. K. SINHAGovt. Licenced Electrical Contractor

Enlisted with W.B. State Electricity D.C.L./T.C.L.

NH-34, Chuanpur More, P.O. BerhamporeDist. Murshidabad, Pin - 742 101, W.B.


C.L. No. 3178, VAT No. 19761895070

PAN No. AAUFS6202Q, P.F. Code No. JL/JNG/38752

GSTIN : 19AAUFS6202Q1ZA

Vendor Code - 505832


A B ENGINEERING

ENTERPRISESELECTRICAL ENGINEERS &

GOVT. LICENSED CONTRACTORS

26A, Sankharitola Street, Kolkata - 700 014

Phone : (033) 2264 0083, Fax : (033) 2264 0533E-mail : [email protected]

Branch : Haldia (W.B.)


R. M. ELECTRICALGovt. Licenced Enlisted Contractor &


Under W.B.S.E.D.C. Ltd.Enlisted No. :

Distribution Enlistment / 2015-16/242

Vill. 2nd Part Jalpai, P.O. BaraghuniP.S. Chandipur, Dist. Purba Medinipur

Mobile : 97326 67271, 96094 14789

C.L. No. 17002, P.F. No. WBCAL/1382838


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I

R. K. ENTERPRISEElectrical Contractor & General Order Suppliers

Enlisted by : WBSEDCL

Chaitanyapur, HaldiaPurba Medinipur, Pin - 721 645

Mobile : 91535 21995, 93329 27319



I

M/s. ROY ELECTRICALSRegd. No. 8885

CONTRACTOR OF W.B.S.E.D.C.L

Netaji Subhash Road, ContaiPurba Medinipur, Pin - 721 401


Vendor Code No. 505753, PAN No. ACLPR2120FGST IN : 19ACLPR2120F1ZP

Prop. : BISWARUP ROYBISWARUP ROYBISWARUP ROYBISWARUP ROYBISWARUP ROY


M/s. R. P. G. CONSTRUCTION(W.B. Govt. Regd. No. L/71137)

Govt. Electrical Enlisted Contractor

Specialist in : Foundation, Construction

Erection, Stringing and other Civil works

of EHT Transmission Line & Sub-Station

29, R. N. Mukherjee Road, Windsor HouseKolkata - 700 001


GST No. 19AAHFR4266J1ZQ


RAINBOW CONSTRUCTIONSpecialist in : Electrical, Civil, Mechanical,

Instrumentation Construction maintenance

work & General Order Supply

Chiranjibpur, HaldiaPurba Medinipur, Pin - 721 604

Fax : 03224-251742 (Off.)Mobile : 94342 42677, 94745 84625

94344 53237, 94342 08942E-mail : [email protected]


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M/s. Ganguly ConstructionW.B. GOVT. ELECTRICAL LICENCE CONTRACTOR, CIVIL ELECTRICAL ENGINEER & TRANSPORT

FABRICATION & GENERAL ORDER SUPPLIERS

Vill. & P.O. Arbelia, Dist. North 24 ParganasBranch : Near St. Paul School, Contai, Purba Medinipur, W.B.

Mobile : 91431 31160, 91430 77080, 94346 20416, 91430 62978, E-mail : [email protected]


M/s. SAHA & GUPTA ENTERPRISE

Govt. Civil, Electrical Contractor & General Order Supplier

Enlisted in - Class-I C.P.W.D., N.F. Rly. & W.B.S.E.D.C.L. II E.C.L. No. : 5279

44, Kuttitola Lane, P.O. & Dist. Malda - 732 101


M/s. J. GUCHHAIT

Govt. Licenced Enlisted Contractor & General Order Suppliers

Under W.B.S.E.B.D.C. Ltd., Enlisted No. R/2015/585/213

Vill. + P.O. Thakurnagar, Dist. Purba Medinipur, Phone : 276140, Mobile : 94349 91010

C.L. No. 9180, PF No. WB/CA/54377, S.C.C. No. 18829


NATIONAL TRADING CO.INDUSTRIAL COMPONENTS

Stockist of : All kinds of Electrical Goods, tools, Pipe, Pipe Fittings, Valve, Hardware Goods,

Gauges, Welding Accessories, Sealing Compound & General Order Suppliers

Vill. Basudevpur (Near SDO Office), P.O. Khanjanchak, P.S. Durgachak, Purba Medinipur - 721 602

Prop. : G. SASMAL, Mobile 9434623674, 81162 79533, E-mail : [email protected]


APEX INDUSTRIESGovt. Contractor & General Order Suppliers

Regd. Office : Padumbasan (W.O No. 5), Tamluk, Purba Medinipur, Pin - 721 636

Mobile : 89679 65597, 80137 38413, E-mail : [email protected]


PUSPA ELECTRICALS CONTRACTORGovt. Electrical Contractor Enlisted of W.B.S.E.D.C.L.

Head Office : Serpur Telengabard, Contai, Purba MedinipurMobile : 99326 26107, 96353 25469



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M/s. Matan Engineering Construction

ENLISTED ELECTRICAL CONTRACTOR W.B.S.E.D.C.L. & GENERAL SUPPLIERS

Mobile : 95634 33802, E-mail : [email protected]

GSTIN : 19BKRPM4277M1Z5, Vender Code No. 504022


RAINBOW CONSTRUCTION

Specialist in : Electrical, Civil, Mechanical, Instrumentation Construction maintenance work & General Order Supply

Chiranjibpur, Haldia, Purba Medinipur, Pin - 721 604, Fax : 03224-251742 (Off)Mobile : 94342 42677, 94745 84625, 94344 53237, 94342 08942

E-mail : [email protected].


M/s. Super ElectricGovct. Licence Electrical Contractor Registered No. 16538

Enlisted by : WBSEDCL

All Electrical Working Job, Installation & H.T./L.T. Panel Repairing Making any Type of Electrical Jobs

Antila, Bagna, Howrah - 711 312 (W.B.)Phone : (03214) 272092, Mobile : 98304 71635, E-mail : [email protected]


SURAJ AGENCYGovernment of West Bengal Approved License holder Electrical & Civil Contractor Specialist in

L.T., H.T. & E.H.T. over head lines, Underground cable lines, Transportation job & all kinds ofSub-Station Structure, Equipments Erection & commissioning works

Enlisted under West Bengal State Electricity Transmission & Distribution Company Ltd.

H.C. Sarkar Lane, P.O. Krishnanagar, Dist. Nadia, Pin - 741 101Mobile : 94343 22781, 95637 07265, E-mail : [email protected]


BAKSH ENTERPRISEGOVT. AUTHORISED ELECTRICAL CONTRACTOR

Vill. Sarulia (Madrasah Para), P.O. Barua, P.S. Beldanga, Dist. Murshidabad (W.B.), Pin - 742 189Mobile : 99320 46259, (A) 97355 26041, E-mail : [email protected]

GSTIN No. : 19AAQFB5433J1Z2


ERECTION STRINGING COMPANY(GOVT. LICENSED CONTRACTOR)

400 K.V., 132 K.V. & 33 K.V. SUBSTATION ELECTRICAL JOBS

Civil Jobs, Heavy Transformar Loading, Unloading, Dragging & Transporting, Overhauling

Office : Avinandan Market, Ground Floor, 9, Jessore Road, Duckbanglow MoreP.O. Hridaypur, Barasat, Kolkata - 700 127

Phone : (033) 2562 6582 (O), Mobile : 98311 40082, E-mail : [email protected]

GST IN : 19AHPA5602K1ZD


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MANOJ SANTRAGOVT. LICENCE ELECTRICAL CONTRACTOR & GENERAL ORDER SUPPLIERS

Kaurchandi, Amalhanda, Purba Medinipur, Pin - 721 134


Service Tax No. DQHPS7051HSD002, Vat No. 19851049904

Enlistment No. CED/185, PAN No. DQHPS7051H, GST No. 19DQHPS7051HIZC


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C D


I

M/S. SAJ ENTERPRISEGOVT. LICENCED ELECTRICAL & CIVIL CONTRACTOR & GENERAL ORDER SUPPLIER

Enlisted Electrical Contractor W.B.S.E.D.C.L.

Office Address :

Bhakuri, P.O. Balarampur, P.S. BerhamporeDist. Murshidabad, Pin - 742 165, (W.B.)


Vender Code : 512717, L.C. No. 20120104324 (15573), Enlistment No. 2015-16/176

PAN No. AAUPZ6661Q, GST No. 19AAUPZ6661Q1Z3, P. Tax No. 192026705527

P.F. Code No. JL/JNG/1029417, E.S.I.C. No. 74000630280001019


]

SONALI CONSTRUCTIONELECTRICAL, CIVIL GOVT. CONTRACTOR & GENERAL ORDER SUPPLIER

Enlisted under W.B. State Electricity Distribution Company Ltd.

(W.B.S.E.D.C.L.)

Vill. Nischintapur, P.O. Gopinathpur, P.S. BeldangaDist. Murshidabad, Pin - 742 134 (W.B.)

Mobile : 89266 54556E-mail ; [email protected]

EWK No. 0670502, GST IN : 19DXEPS7344F2Z0, S.T. Code Regd. No. DXEPS7344FSD001

P.F. No. JL/JNG/0045914/000, Trade Regd. No. 33/2012-13

E.S.I. No. 74000663100001009, Licence No. MSD-129/S/CL/DLE/BER

Electrical Licence No. 20050104277, Vender No. 514279, RE/Enlistment/60/B-2729

Prop. : SAHADATH SK.


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Mobile : 94341 61097, 97357 01226, 97357 01224E-mail : [email protected]

ENLISTED : W.B.S.E.D.C.L.

With

Best

Compliments

From

ABASBARI (Ward No. 6)P.O. Tamluk, Dist. Purba Medinipur

Head Office : Factory :Nischintabasan, Bahichard

Tamluk, Purba Medinipur


279, Sutirmath, P.O. + P.S. BerhamporeDist. Murshidabad, Pin - 742 101, W.B.



WithBestComplimentsFrom

Vill. Hulashpur, P.O. DangaparaP.S. & Dist. Murshidabad, Pin - 742 302

Mobile : 97344 51950

PAN No. AQPPM9116L, GST IN : 19AQPPM9116L1Z2

P. Tax Id No. : 192013801908, EPF No. JLJNG1707907000

ESI No. 74000672000001019

GOVT. CONTRACTOR & GENERAL ORDER SUPPLIER


Berhampore, Bhakuri, Ghoshpara, (Subhas Pally)PO. Chaltia, Dist. Murshidabad, Pin - 742 407, W.B.

Phone : 03482-654465Mobile : 94346 72626/27

Head Office :

Enlisted with WBSEDCL & WBSETCL, NTPC Farakka

Vendor Code No. 1053867

PF Regd. No. R-ENF / SPL / WB / HLO / 36604 / How / 604

ESI No. 74000636430001001, Service Tax No. AEYPB6288HSD001

VAT Reg. No. 19763763096

GOVT. CONTRACTOR, CIVIL, MECHANICAL, STRUCTURAL & ORDER SUPPLIER


With

Best

Compliments

From

Office :Debkunda, P.S. Beldanga

Dist. Murshidabad, Pin - 742 133, W.B.

Mobile : 94349 35893, 97354 20502E-mail : [email protected], [email protected]

GOVERNMENT CONTRACTOR (CIVIL & ELECTRICAL)


34, Mohan Roy Para, P.O. KhagraDist. Murshidabad, Pin - 742 103


GOVT. ENLISTED CONTRACTOR AND GENERAL ORDER SUPPLIERS


74/7, Ukilabad Road, BerhamporeMurshidabad, Pin - 742 101

Phone : 03482-259613, Mobile : 94341 08692E-mail : [email protected]

GOVT. CONTRACTOR & GENERAL ORDER SUPPLIERS


Shankarpara, Bhabta, Murshidabad, Pin - 742 134Mobile : 94340 04244, 81451 21456

E-mail : [email protected], [email protected]

PAN No. : ACJFS4424K

GST No. 19ACJFS4424K1ZP

C.L. No. 11883

Badurtala, Lodha Park, P.O. JiaganjDist. Murshidabad (W.B.), Pin - 742 123


GOVT. CONTRACTOR & GENERAL ORDER SUPPLIER

PAN No. ABRFS6502R, GST No. 19ABRFS6502R1Z6

EPF No. JL JNG0045004000, ESI Code No. 74000666200001099

With

Best

Compliments

From

GST No. 19AAJFB0776H1ZA

Enlisted with W.B.S.E.D.C.L.

Vendor Code : 513866

E-mail : [email protected], [email protected]@gmail.com

Corporate Office :

New Saradapally, Chuanpur

Chaltia, Berhampore

Murshidabad, Pin - 742 101, W.B.

Mobile : 99333 91134 / 94748 95544

Residential Office :

Vill. & P.O. Mahula, (Near Ghosh Fertilizer)

P.S. Beldanga, Dist. Murshidabad

Pin - 742 134, W.B.

Mobile : 99333 91134 / 94748 95544

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