sp-ps-431 rev 1.01

Applies to: Third Parties and SSEPD

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Specification for 36kV Indoor Secondary Switchgear and Equipment

for Joint User Substations SP-PS-431

Classification: Public Uncontrolled if printed Rev: 1.01

Scottish and Southern Energy Power Distribution Page 1 of 22

The author / owner of this document is:

This document has been approved for Issue by: Date of Issue: Review Date:

David Bartlett, Engineering Policy

John Baker, Engineering Policy Manager February 2014 February 2019

1 GENERAL

1.1 This specification is intended to be used by third parties installing substations for adoption, or use, by Scottish and Southern Energy Power Distribution (SSEPD) where the third party designs and constructs the substation, provides the high voltage switchgear, and metering unit and associated ancillary equipment.

1.2 The switchgear is for use on SSEPD 33kV secondary distribution network.

1.3 The switchgear rated current and operational characteristics shall not be less than that at the point of the network to which it is to be connected.

1.4 SSEPD System Planning will confirm if this specification is pertinent to the application or if the specification for Primary 33kV switchgear (SP-PS-026 33kV Indoor Metal Enclosed Circuit Breaker Equipment) shall be used.

1.5 This specification provides notes of guidance for complete 33kV indoor metal enclosed switchgear panels. Including the design, manufacture, testing, and transportation to UK site, off loading, positioning, installation and commissioning.

1.6 Each panel (circuit breaker or ring main unit) is to be totally assembled and tested as a complete unit before despatch.

2 STANDARDS

2.1 Equipment supplied will comply with the relevant parts of the current versions, of the following standards:

Publication Title

ENA TS 12-11 Dry Cable Terminations in HV Switchgear for service rated voltage 12, 24 and 36kV ENA TS 41-36 Distribution Switchgear for service up to 36kV ENA TS 50-18 Application of Ancillary Electrical Equipment

ENA TS 50-19 Specification for standard numbering for small wiring for switchgear and transformers together with their associated relay and control panels BS 7888 Test requirements on accessories for use on power cables

BS EN 50482 Instrument transformers. Three-phase inductive voltage transformers having Um up to 52kV BS EN 50181 Plug-in type bushings above 1kV up to 36kV BS EN 60068 Environmental testing BS EN 60255 Electrical relays

BS EN 60694 Common specifications for high voltage switchgear and controlgear standards BS EN 60137 Insulated bushings for AC voltages above 1kV BS EN 60529 Degrees of protection provided by enclosures ( IP Code ) BS EN 61869-2 Instrument transformers. Additional requirements for current transformers


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Publication Title

BS EN 61869-5 Instrument transformers. Additional requirements for capacitor voltage transformers

BS EN 61869-3 Instrument transformers. Additional requirements for inductive voltage transformers

BS EN 62271-100 High-Voltage switchgear and control gear. Alternating current circuit breakers

BS EN 62271-102 High-Voltage switchgear and controlgear. Alternating current disconnectors and earthing switches.

BS EN 62271-103 High-voltage switchgear and controlgear: Switches for rated voltages above 1 kV up to and including 52 kV

BS EN 62271-200 AC metal-enclosed switchgear and control gear for rated voltages above 1 kV and up to and including 52 kV

BS EN 62271-201 A.C insulation - enclosed switchgear and control gear for rated voltages above 1kV and up to and including 52kV. BS EN 62271-1 High-voltage switchgear and control gear. Common specifications. BS EN ISO 9001 Quality management systems requirements

2.2 Approved plant is detailed in SSEPD document TG-PS-148, Distribution Plant Catalogue.

2.3 Where a new design of switchgear not already approved by SSEPD is proposed, then the provider shall state whether the switchgear conforms to the Energy Networks Association Engineering Recommendation G79 and hold a valid Notice of Conformity (NoCC). That is the interrupters, disconnectors, housing, cable box and mechanism assembled together shall be tested as an assembled unit and that copies of test certification and accreditation shall be included with the submission.

2.4 Where this is not the case the supplier shall supply a list of exceptions, stating where the switchgear does not comply with ENATS 41-36 and this specification. SSEPD will then assess the plant. The Quality and Approval process may take some time and attract a charge for the work. In addition there may be a requirement to undertake modifications (at their own expense) to the operational and safety aspects of the equipment to comply with SSE Power Distribution working practices and to provide operational spares where replacements cannot be made for SSEPD standard strategic stock.


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3 STANDARD RATINGS

1. Power System Particulars (minimum parameters) Rated Voltage kV 36

System Frequency Hz 50

Arc quenching medium SF6 or Vacuum

Ambient air temperature C Minimum -5 Maximum 40

24hr average temperature C 35

Location Indoor

2. Rated Values (common): Rated Insulation Level (BIL) kV 170 Power Frequency Withstand Voltage (1 minute) kV 70

Rated normal current of busbars A 630 / 1250

Rated short time withstand current kA 25

Rated short circuit making current kA 50

Rated short-circuit breaking current kA 20

Rated short time withstand current and duration kA / sec 25 kA / 3 secs

Arc Fault Current and duration kA / sec 25 kA / 1 sec

Rated normal current A 630

Rated capacitive switching currents Class C1

Earthing Switch Mechanical Endurance Op cycles 1000 cycles

2. Ring main switch disconnectors: Rated line-charging breaking current A 2

Rated cable-charging breaking current A 20

Classification for mechanical endurance Class M1 (2000 ops)

Classification for electrical endurance Class E3

3. Ring main earthing switch: Classification for electrical endurance Class E2

4. Circuit breaker: Out of phase making and breaking current kA 6.25

Rated line-charging breaking current A 10 / 16

Rated cable-charging breaking current A 25 / 50

D.C. Time constant ms 45

D.C. Component % < 20

Classification for mechanical endurance Class M2 (10,000 operations)

Classification for electrical endurance Class E1

Rated operating sequence O 3 min CO 3 min CO

Operating mechanism type Charged Stored energy spring


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4 LIFETIME MAINTENANCE COSTS

4.1 SSEPD require switchgear systems that have a minimal requirement for servicing. Therefore products sealed for life, that have lifetime lubrication systems applied at the time of manufacture, with long recommended inspection intervals, a demonstrable high component and overall product reliability history and manufactured within quality assurance systems laid down in ISO 9001 are preferred

5 OVERALL EQUIPMENT DESIGN

5.1 The equipment shall be of a modular design forming a composite switchboard / ring main unit.

5.2 Each incoming cable will be controlled by a circuit breaker with cable earthing facility; an incoming disconnector may be supplied with an outgoing circuit breaker with cable earthing facility, see figures 1 to 4 below.

5.3 The outgoing customers cable must have a means of isolation, earthing and a point of testing.

5.4 Cables and cabling installation must comply with the SSEPD specifications detailed in SP-PS-239.

5.5 Where the customers G59 circuit breaker is housed in the same substation building as the SSEPD incoming circuit breaker, the SSEPD / Customer interface boundary shall be on the busbar side connection of the SSEPD incoming circuit breaker or SSEPD circuit breaker cable box.

5.6 SSEPD will have ownership of the incoming circuit breaker, SSEPD tripping and Scada batteries.

5.7 For non-rotating machine generator connection, a three phase voltage reference may be taken from the SSEPD voltage transformer fused at 2 Amp.

5.7.1 Third parties will not have access to these fuses and will provide a set of links to isolate the supply from their equipment.

5.8 See schematic drawings for connection; Figures 1 to 4.

5.9 Where more than a single SSEPD connection is required only the standard connection shall be accepted in line with Figures 1 and 2.

5.10 The customer will retain ownership of the substation building and ancillary equipment and will be responsible for inspections and maintenance in line with ESQC Regulations and best industry practice.


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Figure 1: Standard Connection Composite Switchgear

Figure 2: Standard Connection RMU Switchgear


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Figure 3: Minimum Scheme Composite Switchgear

Figure 4: Alternative Connection Scheme Composite Switchgear


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6 DEGREE OF PROTECTION FOR THE ENCLOSURE AND PARTITIONS

6.1 Equipment shall have a degree of protection not less than IP30.

7 TYPE OF ENCLOSED SWITCHGEAR

7.1 The enclosure will be metal-enclosed and comply with the requirements of BS EN 62271-200.

8 PROTECTION GRADE OF THE INSULATION

8.1 Protection grade to comply BS EN 62271-201, as appropriate.

9 INTERNAL ARC TESTING

9.1 Only equipment fully internally arc tested and fully compliant with BS EN 62271-200 Appendix AA is acceptable.

9.2 All equipment is required to be tested to the rated short time withstand current specified in the schedules for 1 second.

10 CONTROLLED EXHAUST GAS VENTING

10.1 In the event of an internal arc, the by-products are to be directed away from an operator in front of the equipment. The pressure relief system will be designed to conform to the switchgear manufacturer recommendations.

10.2 The provider is to ensure that the minimum ceiling height and volume of the switchroom meets the design criteria specified by the switchgear manufacturer for internal arc gas venting.

10.3 Gas vent boxes and flaps must carry a warning label.

11 INTERRUPTING MEDIUM

11.1 Only vacuum interrupters (configured in air or gas) or SF6 circuit breakers are acceptable. Manufacturers must state the total mass of SF6 gas in each panel.

12 INDICATION OF SF6 GAS PRESSURE

12.1 A Go/ No Go (Green / Red sector type) gas pressure indicator shall be supplied where normal operating gas pressure is marginally above atmospheric pressure, pressure gauges should be temperature compensated.

12.2 Where SF6 gas is used for insulation only (not arc interruption) each gas compartment shall be provided with a pressure switch. The indication of the single stage pressure switch shall be given at the minimum functional pressure.

12.3 Circuit Breakers using SF6 gas for insulation only will withstand the Rated Insulation Level at minimum functional pressure.

12.4 Where SF6 gas is used for arc interruption two sets of pressure monitoring switches are required. One set for alarm and one for protection trip. Protection inhibit shall prevent protection operation but shall allow remote and local electrical tripping.


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12.5 For these conditions remote alarms will be required as inputs to the SCADA system. Alarm levels should be indicated by volt free contacts and passed to the relay to be communicated to Control.

12.6 Each separate gas compartment shall have independent gas monitoring.

13 SF6 GAS FILLING MANIFOLD

13.1 A Hanson or DILO DN6 coupling is required with a retained and gas tight dust cap.

13.2 Manufacturers may offer alternative gas fittings subject to SSEPD approval.

13.3 Adaptors to fit the alternative gas fitting to the Hanson/DILO coupling shall be supplied on a per-switchboard basis free of charge.

14 PARTICULARS OF THE OPERATING DEVICES (BS EN 60694, PARAGRAPH 5.6)

14.1 The operating device shall either be a motor charged, spring operated, magnetic actuated or stored energy design.

14.2 The operating mechanism shall be capable of closing and immediately re-opening at the full short circuit rated current.

14.3 Directly driven mechanical indication of circuit breaker and earth switch status (On / Off) together with Spring charged and Spring free condition will be provided.

14.4 Electrical contacts are required for input to the SCADA system.

14.5 Positively driven Class 1 (BS EN 60694) auxiliary switches will be provided to the requirements of the scheme.

14.6 The switchgear shall be fully interlocked to prevent maloperation. This shall prevent operation of the disconnector or earth switch unless the associated CB is open.

14.7 Software interlocking is not permitted.

15 CIRCUIT & BUSBAR EARTHING

15.1 Circuit breaker equipment with feeder earthing switches either of fault make or of disconnector design with the earth circuit subsequently made by the circuit breakers are acceptable.

15.2 Electrical tripping shall be made inoperative where the circuit breaker is used to apply the Earth. Trip circuits shall be restored on removal of the earth, before return to normal service is possible.

15.3 Fault-making earthing switches shall be manually operated, spring assisted and integrally interlocked with the circuit breaker.

15.4 Earth switches which require no maintenance during normal operation are preferred.

15.5 Maintenance requirements and frequency must accompany the submission for approval.


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ADDITIONAL REQUIREMENTS FOR NON-WITHDRAWABLE CIRCUIT BREAKER EQUIPMENT

15.6 Capacitively Coupled Test Sockets

15.6.1 Three phase capacitively coupled test sockets will be included on each panel and shall be connected permanently to the cable box side of the circuit breaker / disconnector and to each side of a bus-section circuit breaker to enable tests to be carried out.

15.7 Testing of Metalwork normally live

15.7.1 A testing instrument suitable for indicating the presence of voltage will be provided. This will to be used to determine whether normally live metalwork is dead before circuit main earths are applied. Devices should be provided to allow testing of all three phases at the same time.

16 EMERGENCY TRIP

16.1 Under the Electricity at Work Regulations there must be provision of an emergency trip to disconnect all supplies to the site in an emergency. This is detailed in TG-PS-671 revision 1.01: figures 5 and 6 shown below.

EPB

MVAJ 21 Relay

Trip Coil of SSEs incoming 33kV circuit breaker

Customer Owned

SSE Owned (Adopted)

Customer Supply

SSE Supply

Isolation link for EPB testing

purposes

K1K*

K3

Contact to RTU for ENMAC alarm

Emergency Trip

X962

X766 Figure 5 Emergency Push Button remote to the SSE switchroom (eg in 3rd partys switchroom)

EPBTrip Coil of SSEs

incoming 33kV circuit breaker

Isolation link for EPB testing purposes

K1

K*

K3

6A

16A

SSE Protection

J2J1

Contact to RTU for ENMAC alarm

Emergency Trip

X962

X766 Figure 6 Emergency Push Button affixed to the SSE switchroom


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17 LOW VOLTAGE SUPPLY

17.1 A 100A low voltage 230V ac supply will be provided from the customers low voltage network.

17.2 An LVAC panel (which can be a Consumer Unit) is required to connect the external LV supply and operate LV equipment on individual circuits.

17.3 The LVAC panel shall consist of Type B MCBs rated at a minimum of 16A connecting the following equipment.

A 13A fused spur supplying the trip/close battery charger

A 13A fused spur supplying the scada battery charger.

A minimum of one 13A 3 pin double socket protected by an RCD.

A 13A fused spur supplying the 230/110V transformer.

2 way 16A ways.

17.4 A 16A, 3 pin industrial, 230V socket will be provided to connect an external generator with an access facility to the building or within a secure external fitting connected via a changeover switch to the LVAC panel.

17.5 A loss of supply relay will be provided to indicate loss of low voltage supply to substation auxiliary supply.

18 BATTERY/CHARGER UNITS

18.1 Batteries and Chargers will comply with SP-PS-008.

18.1.1 24 Volt 100 Ampere hour approved battery and charging equipment will be required for SCADA / telecontrol, control and protection duty for the sole use of SSEPD.

18.1.2 108 Volt 200 Ampere hour approved battery and charging equipment will be required for tripping, closing and motor wound spring duty for the sole use of SSEPD.

18.2 Batteries shall be capable of running all equipment for a minimum of 72 hours following loss of mains supply.

18.3 The standing load of the SSEPD and third party equipment must be declared and met by the respective batteries.

18.4 It is the customers responsibility to supply and install the batteries and battery cabinets, all ac and dc cabling required and all terminations.

19 INSTRUMENT TRANSFORMERS

19.1 Current Transformers

19.1.1 All current transformers will be thermally rated for the full Circuit breaker current rating at the ratios specified.

19.1.2 CT options available for joint user connections are:


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Protection 200/100/1A 15VA 5P10 / 7.5VA 5P10. Metering 200/100/1A 0.2S 7.5VA / 0.5S 5VA.

Protection 800/400/1A 15VA 5P10 / 7.5VA 5P10. Metering 400/200/1A 0.2S 10VA / 0.2S 5VA.

Protection 800/400/1A 15VA 5P10 / 7.5VA 5P10. Metering 800/400/1A 0.2S 10VA / 0.2S 5VA.

19.1.3 Current transformers shall comply with BS EN 60044 Part 1.

19.2 Voltage Transformer Arrangements

Primary Winding: Specified System Voltage (e.g. 33,000V)

Secondary Windings:

Winding 1: 110V Class 0.5 30VA for COP 2 main meter and check meter.

Winding 2: 110V Class 0.5 30VA for COP 2 non-settlement burden

Arrangement: 3 phase 5 limb VT or 3 single phase VTs.

Function: Protection and metering to COP 2 Standard; appendix C.

19.3 The 5 limb 3 phase or 3 single phase voltage transformers arrangements shall have the HV star point earthed and the neutral of each secondary winding earthed through a bolted link.

19.4 Solidly connected single phase non-withdrawable voltage transformers are acceptable, provided an SSEPD approved means of primary and secondary isolation is provided for operational purposes.

19.5 Plug in C type connectors with flexible single core cable may be used for the VT connection.

19.6 Busbar connected voltage transformers will have fused HV connections and method of Isolation from the Busbar.

19.7 Metering Current & Voltage Transformers

19.8 Separate fused supplies are required for main meter, check meter and an additional burden. Metering voltage LV isolation arrangements will be designed to accept SSEPD standard security seals.

19.9 Metering voltage LV isolation arrangements will be designed to accept SSEPD standard security seals.

19.10 Metering instrument transformers will be tested and certified as detailed in Appendix C. The routing of the certification documentation is critical, as are the requirements for accuracy testing. The supplier will provide this information at the appropriate stage in the manufacturing cycle.


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20 OPERATING MECHANISM CONTROL SCHEMES

20.1 Standardised Protection (Protective Relays)

20.1.1 The circuit breaker control scheme will be fully engineered to provide anti-pumping facilities, trip circuit supervision and an interface with protection and related control scheme specified in Appendix 1.

20.1.2 The preferred protection arrangements detailed in the appendices use numerical protection and control relays with programmable logic (PSL) for auto-reclose and other duties.

20.1.3 All tripping circuits from protection relays (inputs and outputs) are to be wired through the test block. Trip isolation links will be required with a separate link provided for main and back-up protection.

20.1.4 SSEPD may provide outline protection schemes based on existing experience. These schemes are based on particular relay types. Suppliers may offer alternative relays provided that they are approved by SSEPD prior to use and the scheme functionality is retained.

20.1.5 Where relays of a different type are provided (by agreement) in lieu of the relays specified, the manufacturer shall ensure supply of associated programming software. This shall be provided at no cost to SSEPD.

20.2 Number and type of spare auxiliary switches

20.2.1 All spare auxiliary switches on all panel types shall be wired out to terminal blocks.

20.2.2 A minimum of 4 normally open and 4 normally closed switches in excess of the scheme requirements shall be provided on Feeder and Metering panels.

20.3 Circuit breaker trip / close facilities

20.3.1 Equipment will be fitted with a socket for connecting the plug of a trailing lead with a remote end trip / close push button.

20.3.2 One trailing lead with a minimum length of 15 metres and fittings will be supplied per switchboard.

20.3.3 The remote trip / close facility shall be wired to the main protection relay of each panel.

20.4 Feeder Current and Voltage Monitoring

20.4.1 Current and voltage monitoring shall use the digital relay display on the Main or Back Up protection relays.

20.4.2 There are no requirements to have a panel mounted ammeter.

20.4.3 Analogue interfacing to SSEPD SCADA system will preferably use a serial connection via DNP3 connection from the Protection relay.


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20.4.4 Alternatively 0-10mA or 4-20mA current and voltage transducers with a minimum of 25% over-range capability dependant on CB Type and Number shall be specified at the panel order stage.

20.5 Control Circuit Protection

20.5.1 Control circuits will be protected by a device which can also be used as a positive means of isolation. Fuse carriers and bases are acceptable.

20.6 Control Switches

20.6.1 Operating switches shall have push to turn locking facility complying with BS EN 62271.

21 SCADA SYSTEM INTERFACE

21.1 SCADA Interface

21.1.1 Input / output connections selected from Appendix 2 for the particular switch-panel type are required for interfacing remote control, alarm, indication and analogue signals with the SSEPD SCADA system for panel types where serial comms are not used.

21.2 SCADA cabling

21.2.1 It is the responsibility of the customer to supply, install the cabling required for SCADA communications and terminate this at the switchgear connection.

21.2.2 SSEPD will be responsible for terminating the unit at the RTU connection point.

21.3 SCADA related small wiring

21.3.1 All SCADA small wiring will terminate on Weidmuller RSF1 links (SAKR_ 041222) terminals with isolating link or approved equivalent. Terminals will be mounted in the front of the control panel in groups of 20 to suit the 10 pair telecontrol cable; 1/0.6mm SWA to ENA_TS_09-6. Provision shall be made for the RS485 serial communication single pair cable. These shall be mounted ion a TS32 DIN rail.

21.4 Panel mounted control switches

21.4.1 Rotary switches associated with the SSEPD SCADA system will be supplied where required.

22 Anti-Condensation Heaters

22.1 Anti-condensation heaters will be fitted to each switch panel installed with fuse and link in the heater supply circuit.

23 AUXILIARY SUPPLIES

23.1 A single 230/110V transformer rated at 1kW shall be supplied.

23.2 A single 110V AC supply for the panel heaters will be connected into one end panel and buswired through the switchgear suite.


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23.3 A sump pump with high alarm will be supplied; access to the sump pump should be provided by keyed and not bolted covers. Refer to SP-PS-430.


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24 SMALL WIRING

24.1 The suppliers standard small wiring, marking and end identification will be acceptable provided the terminal rail interface markings correspond to site specific requirements.

24.2 Multicore cables shall be terminated using Weidmller crimped hooked blade cable lugs.

24.3 Small wiring terminal blocks shall be spring clamp, spring loaded, and small wire terminations of the Weidmuller type WDU6 SL mounted on TS32 DIN rails.

24.4 Alternative terminals may be considered on production of sample terminals for approval.

24.5 All current transformer secondary wiring will not be less than tri-rated cables 2.5 mm stranded conductor with Black insulation.

25 MULTICORE CABLE TERMINATIONS

25.1 A gland plate will be provided in an approved accessible position within the LV compartment to terminate the multicore steel wire armoured cables. Facilities are to be provided to route the cables from the cable trench / basement to the LV compartment.

25.2 Where necessary the manufacturer will install cable tray support to facilitate the routing of cables from a top protection panel to the rear of the Circuit Breaker cubicle to enable the ease of installation of the multicore cables.

25.3 Where protection panels are mounted at the bottom of the Circuit Breaker cubicle and cabling can be routed directly into the cable trench / basement, the cable tray will not be required.

26 HV CABLE TERMINATION ARRANGEMENTS

26.1 HV Cable termination shall be either:

a. 1250A separable connectors (Outer cone) with copper connections and 16mm studs.

b. CONNEX Type 3 1250A connectors (Inner cone) may be used.

26.2 Panels should allow for the connection of the following number of cables per phase based on the rating of the circuit breaker:

630 A One connector per phase

1250 A Two connectors per phase

Where separable connectors are utilised, cable box gland plates shall be non-ferrous split plates with 70mm holes for cable access.

26.3 All cable terminations must comply with ENA TS 12-11.

27 FACILITIES FOR CABLE TESTING

27.1 Facilities will be designed into the equipment to enable cable circuit testing to be carried out in safety. Full details shall be provided with the submission.


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27.2 Where a dedicated HV cable test access is provided, opening of the cable test access cover shall only be possible with the circuit earth ON.

27.3 All covers requiring removal for test access shall be interlocked so that the cover cannot be removed unless the circuit earth switch is ON. Where applicable an indication on the front panel of the circuit breaker equipment shall indicate when the cover is open.

27.4 Where a dedicated cable access cover is provided, provision shall be made for locking the cover in the closed position with an operational padlock.

27.5 In no instance shall it be possible to replace the cover with test equipment in place or energise the primary circuit with test access covers off.

28 EQUIPMENT RATING PLATES

28.1 Rating plates shall comply with BS EN 62271 and will include short circuit making current (peak) details for both circuit breaker and earthing switch.

29 LABELS

29.1 Circuit label facilities will be supplied at both the front and rear (if accessible) of the switch panel. Panels designed for mounting over basements will have circuit labels mounted in a prominent position under the panel.

29.2 All internal and external fuses, links, alarms, LEDs, indications, Relays etc will be clearly identified by means of permanent labels mounted adjacent to the relevant item..

30 PADLOCKING

30.1 Operational locking facilities will be sized to allow SSEPD standard operational and safety padlocks with a 5mm shank to be used without adaption. A means of locking off circuit breaker mounted mechanical and electrical trip and close controls is required.

30.2 All doors and exposed fuses on SSEPD owned equipment will be supplied with provision for locking with standard SSEPD padlocks.

31 BUILDING REQUIREMENTS FOUNDATION ARRANGEMENTS & DIMENSIONS

31.1 Details of foundation and cable trench requirements (including any structural steelwork, etc.) together with full dimensions of the equipment are to be submitted with enquiry.

31.2 Minimum access clearances for cable jointing, circuit breaker removal and panel replacement (for fixed mounted circuit breaker equipment) shall be maintained in accordance with manufacturers recommendations.

31.3 Details of the substation building and ancillary equipment can be found in SP-PS-430 Specification for 36kV joint User Substation Buildings.

32 TRANSPORT, STORAGE, ERECTION AND MAINTENANCE INSTRUCTIONS

32.1 The transport, storage and erection is the responsibility of the third party.

32.2 SSEPD will only be responsible for maintenance of its equipment.


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32.3 Following installation, the switchgear is to undergo power frequency testing for 1 minute before being energised on the network.

32.4 A complete set of documents including; test certificates, detailed instructions for the transport, storage, erection and maintenance of the equipment shall be provided. One set of paper documents are to be held with the switchgear and one electronic set to be sent to the relevant Distribution Major Projects (DMP) Engineer. These documents must be received by SSEPD DMP prior to hand over of the SSEPD equipment.

32.5 Updated, as built schematic diagrams must be given to SSEPD prior to hand over of the SSEPD equipment.

33 TOOLS & SPARES

33.1 Details of special tools, accessories and recommended spares are to be detailed on the submission.

33.2 Tools required for the operation and maintenance of the switchgear, or any other specialist use, are to be provided and supplied in a suitable storage container.

33.3 All items are to be clearly identified with information as to their function.

33.4 Where switchgear mounted VTs are fitted with HV fuses one set of spare fuses shall be provided.

34 COMMISSIONING

34.1 Specification for site testing shall include:

34.1.1 Confirmation of all parts delivered (including test bushings).

34.1.2 Record of test instruments used and calibration dates.

34.1.3 Ductor reading for all joint connections (busbar) assembled at site.

34.1.4 Torque settings for all connections assembled at site.

34.1.5 CT Flash tests and mag. curves if factory results are not available on site.

34.1.6 Relay secondary tests.

34.1.7 Relay Primary current test recording (O/C, E/F and SEF operate values). Tests are to be carried out at nominal settings if no final settings available at time of test.

34.1.8 Operation of Trip relays.

34.1.9 HV Pressure test & insulation resistance check on HV equipment.

34.1.10 Insulation resistance check on panel wiring.

34.1.11 Mechanical operation tests on CB / Isolator / VT isolation / Interlocking.

34.1.12 Proving of phasing devices.

34.1.13 Scada indications and operation.

34.2 Commissioning records giving details of the above as a minimum shall be given to SSEPD as part of the handover of the SSEPD equipment.


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35 APPLICABLE STANDARDS

35.1 Third Parties must obtain copies of non SSEPD Standards, such as BS or ENA documents, from the issuing organisations at their own expense. These documents may be subject to copyright.

35.2 Copies of documents required under ENA G81 will be available on the SSEPD website.

35.3 Should Third Parties require copies of other SSEPD documents these can be requested from the SSEPD Power Systems Document Administrator, Inveralmond House, 200 Dunkeld Road, Perth PH1 3AQ.

35.4 There will be a cost of 150 for each copy of each document requested to cover administration and copying costs. Note documents containing confidential information will not be issued.


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Appendix 1: Protection

Feeder (Various including metering)

Fitted with the following

Main Protection Relay (Micom) P143 3114M0401 with additional input board

Communications DNP3

Relay Watchdog alarm Hard wired

Analogues Current, Volts, MW, MVAr via the main protection relay

Test Blocks MMLG02

Metered Generation Feeder with G59 and PQM / Containerised switchboards

Fitted with the following:

Main Protection Relay (Micom) P341

Back Up Protection Micom P122

Local Control Relay MMLZ31

Control Switches (A/R, SEF) Spring return to centre

Communications DNP3

Relay Watchdog alarm Hard wired

Analogues Current, Volts, MW, MVAr, Frequency

Test Blocks MMLG02 (1 per relay)

Power Quality Meter Ametek Precision Instruments PQ&R 128 including wedding ring CTs and telephone line share unit

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Appendix 2: Requirements for SCADA interface I / Os

Remote controls, remote alarms, remote indications and analogues from individual switch-panel option types will be required, selected from the following list to suit the particular option associated with SSEPD SCADA system.

SCADA communications should be via a serial connection to the SSEPD RTU using DNP3. Logic and protection files must be provided for all relays to SSEPD requirements. Factory testing of the first of each panel type will be required.

Communications should be via hard wire only where serial communicating relays are not fitted to panels

Indications

Circuit Breaker closed / open Double bit

Spring Charged Single bit

Earth Selector closed Single bit

Telecontrol On Single bit

Auto-reclose In / Out Double bit

FPI Operated Single bit

Busbar Selector Closed Single bit

Alarms

(all alarm contacts are to be wired out from protection including unused alarm outputs)

SF6 Gas Low Single bit

Protection Defective Single bit

Auto-reclose Successful Single bit

Trip Circuit Fail Single bit

Relay Watchdog* Single bit (separate hard wired alarm for main and back up relay)

Loss of mains supply. Single bit

High water level. Single bit

Controls

Circuit breaker Open / Closed Double bit

Auto-reclose In / Out Double bit

Analogues

Current, Voltage, Power, Reactive Power, Frequency All CB panels

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Relay Watchdog alarms shall be connected via bus wiring as follows:

- Main relay watchdog

- Back up relay watchdog

- Common

- Buswires shall be terminated using Weidmuller RSF1 links.


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Appendix 3

Requirements for Metering Current and Voltage transformer test certificates

Test certificates for Current Transformers

Test certificates are to be submitted by the supplier to the Large Power Metering department. This testing is to be carried out in accordance with BS EN 61869, with the following additional requirements:

i. All secondary burdens used for test purposes shall have a power factor of 0.8 lagging.

ii. Combined ratio and phase angle errors shall not exceed 0.5% when measured between 1% and 120% of the rated current.

Combined error can be calculated from the formula: - R + (K x P) where:

R = ratio error (in %)

P = Phase angle error (in minutes)

K = Factor to be applied for two conditions:-

a) K = 0 (power factor = 1)

b) K = 0.05 (power factor = 0.5)

The test certificate for each current transformer verifying compliance with the specified limits of accuracy will include the test results in the format as shown in Table A below:

TABLE A: PRESENTATION OF CURRENT TRANSFORMER ACCURACY TESTS

VA/ PERCENTAGE OF PRIMARY CURRENT

PF 1 5 20 100 120

RATIO ERROR %

PHASE ANGLE ERROR (MINS)

COMBINED ERROR %

K=0

COMBINED ERROR %

K=0.05


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Test certificates for Voltage Transformers

Test Certificates are to be submitted by the Supplier to the Large Power Metering department. This testing is to be carried out in accordance with BS EN 61869 with the additional requirement that the test certificate will indicate ratio and phase angle errors for burdens of 2VA, 5VA and 10% of the rated burden at 0.8 power factor lagging.

The test certificate for each voltage transformer, verifying compliance with the specified limits of accuracy and to include the test results as shown in table B:

TABLE B: PRESENTATION OF VOLTAGE TRANSFORMER ACCURACY TESTS

2VA 5VA PERCENTAGE OF RATED BURDEN

10 25 100

RATIO ERROR %

PHASE ANGLE ERROR %

Routing of CT and VT Test Certificates

One copy of each test certificate will be forwarded by the contractor to the Large Power Metering department (details on FO-MET-141) with a second copy placed in the Pilot box (in a plastic bag). Where certificates are hand-written, they must be legible and easily read.

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