SU TU TRANG (STT) FULL FIELD DEVELOPMENT PHASE I

SU TU TRANG (STT) FULL FIELD DEVELOPMENT PHASE I

SU TU TRANG (STT) FULL FIELD DEVELOPMENT PHASE I

ST-LQ BATTERY AND CHARGER SIZING CALCUALTION

Vector InfoTech. LtdPage 7 of 10PROJECT SPECIFICATIONS

The following Specifications shall be applied to the subject work2014-4874-3L-0001230VAC Uninterruptible Power Supply (UPS) SpecificationENVIRONMENTAL CONDITIONSAll equipment and material located outdoors shall be suitable for corrosive offshore environment. The environmental and climatic conditions to which the electrical equipment and materials will be subjected to are given below: Max ambient air temperature, external 35 C Min ambient air temperature, external19 C Max relative humidity, external100% AtmosphereSalt laden marine

The Switchgear room/E-House building will be positively pressurized and air conditioned. The normal HVAC operating conditions shall be as follows:

Temperature23 C 2 C Relative Humidity 50% 10% RH

DESIGN CRITERIABATTERY TYPE

As per the requirement of the specification no. 2014-4874-3L-0001, 230VAC Uninterruptible Power Supply (UPS) Specification, the following factors to be consider for the sizing of the battery ampere-hour capacity. Battery is VRLA (Valve Regulated Lead Acid) type with limited maintenance, End of discharge shall not be lower than 1.84 V per cell at 25 C, Design margin = 10% , Ageing factor = 1.2, Battery shall have design life of 20 years.

SIZING CALCULATION AND SELECTION FOR ST-LQ battery and chargerGENERAL

The calculation is based on the recommendation of IEEE 485 standards and application guides as available. In the absence of suitable standard criteria, the decisions are taken based on sound engineering judgment and best industrial practice.LOAD LIST AND AUTONOMY TIMES

The list of power consumption and autonomy time of 04 hours for PAGA at ST-LQ is provided in Appendix 1. CHARGER SIZING

Sizing of the Charger shall take into account the peak load operation to ensure that the charger is capable to supply electrical power during those peak periods without requiring the battery to discharge un-necessarily. Below is the table summarizing the expected loads to be supported by the Charger and Battery System.Load DescriptionRating (VA)

PAGA SYSTEM A&B3,736.33

10% Design Margin373.63

Total design Load4,109.96

BATTERY SIZING PARAMETER

The sizing of the battery ampere hour capacity will be done based on the absolute power consumption to avoid over sizing of the batteries. Total load required to be supported by the battery bank would be as follows: Battery load profile is shown at figure 1 which is based on design load (Appendix 1) Battery is designed based on typical data as below: Battery system nominal (Unom): 48V DC Allowable input voltage operating window +/- 10%: 52.8V / 43.2V End of voltage (Uend): 1.85V (to be chosen as per Enersys Battery data) Battery Efficiency: 95% Recommended recharge voltage / cell in floating (Uchr) at 250C: 2.25VBased on above condition, minimum number of cell required:Number of Cell = Umax / Uchr = 52.80 / 2.25 24 cellBattery shall support the loads for a minimum period of 4 hours according to the below load profile below.4 hours85.62 A4,109.96 VA

Figure 1. Load Profile (Design Load)Battery bank voltage to be used is the 48V DC. Normally, has an input voltage operating window of +10% and -10% nominal voltage. Taking a worst case situation, the battery minimum output voltage would be: Battery min. voltage = 48 x 0.9 = 43.2V Battery discharge current at this voltage level is as follows: Discharge current for 4 hours autonomy Id= Total Battery Design Load / Minimum battery bank voltage= (Total design Load x Power Factor / Efficiency) / Minimum battery bank voltage= (4,109.96 x 1 / 0.95) / 43.2 V= 100.15 A

To calculate battery cell, it is described by following cell sizing worksheet.

(1)(2)(3)(4)(5)(6)(7)

LoadChange in loadDuration of periodTime to end of sectionAh/A Capacity at T min Rate(3) * (6) Required section size

Period(Amp)(Amp)(minutes)(minutes)KtPos valueNeg value

Section 1

1A1= 100.15A1-0= 100.15M1=240T=2404.802480.92

Total (F)480.92

Note: The Kt factor is calculated by dividing the rated capacity of the cell in Ah by the discharge current at time period, refer to typical manufacturer sheet attached. The battery type is 12V170F, 170Ah with Kt = 170/35.4 = 4.802 at T =240 minutes. Uncorrected battery cell size = Current x Kt = 100.15 x 4.802= 480.92 AhTaking into consideration a battery ageing factor of 20%, design margin of 10% and the temperature correction factor (base on battery performance data). Temperature factor=1 / Factor from Temperature Correction Chart

=1 / 1.03

=0.971

The selected battery shall have as a minimum the following capacity; Req. batt. Ah capacity=Uncorrected battery cell size x Ageing factor x Design margin x Temperature factor

=480.92 x 1.2 x 1.1 x 0.971

=616.41 Ah

The battery final selection: Enersys, Type 12V170F

CHARGER SIZING

Battery charger sizing shall take into account the battery charging current. The below table provides summary of the expected load supplied by charger.Load DescriptionRating (VA)

PAGA SYSTEM A&B3,736.33

10% Design Margin373.63

Total design Load4,109.96

Thus the rectifier unit selected shall have, as a minimum, the following capacity:Minimum Charger Current=(Total Charger Design Load x Power Factor/ Nominal Voltage) + 10% x Req. batt. Ah capacity

=(4,109.96 x 1 / 48) + 10% x 616.41

=85.62 + 61.64

= 147.26 A

The selected rectifier rating: 175A.SUMMARYBattery, Charger Sizing summary for ST-LQ is as follows:

DescriptionST-LQ Charger

1. LOAD SUMMARY

Design Load (VA)4,109.96

2. BATTERY SIZE SUMMARY

Minimum Required Available Current (A)100.15

Calculated Number of Cell / Battery24 cell or 4 battery (6 cells/battery)

Calculated Battery Capacity @ 25 C (Ah)616.41

Selected Number of Cell / Battery16 Battery Bank of 12V170F Number of String for Battery Bank: 4 Total Amp.Hr of Each String: 170 Total No of Battery in Each String:4

Selected Capacity @ 25 C (Ah)680 Ah

3. CHARGER SIZE SUMMARY

Minimum Required Charger Rating (A)147.26

Selected Charger Rating (A)175A

APPENDICES

Appendix 1 Power Consumption Load List for ST-LQ (2 page)Appendix 2 ENERSYS Battery Performance Data (1 pages)

Appendix 1 Power Consumption Load List for ST-LQS/NBrandDescriptionQuantityUnitPower (AC/DC)U (V)I (A)P (W) Total Power (Watts) Heat Distribution (Btu/Hr) Remarks

ST-LQ

1PAGA System A

1.1IndustronicAccess Unit2EA48VDC480.20 9.60 19.20 65.51

1.2IndustronicExchange Board1EA5VDC52.00 10.00 10.00 34.12

1.3IndustronicIntercom station15EA48VDC480.10 4.80 72.00 245.67

1.4IndustronicDDSI15EA48VDC480.10 4.80 72.00 245.67

1.5IndustronicLine Monitoring ring2EA24VDC240.18 4.32 8.64 29.48

1.6IndustronicDigital Exchange 1EA5VDC51.00 5.00 5.00 17.06

1.7IndustronicLinecard Digital Intercom1EA5VDC50.40 2.00 2.00 6.82

1.8IndustronicPower supply control1EA3VDC31.00 3.00 3.00 10.24

1.9IndustronicAmplifier 4EA48VDC486.56 315.00 1,260.00 4,299.30

2IndustronicDC/DC convertor -11EA24VDC242.53 60.72 60.72 207.20

2.1IndustronicCPU1EA5VDC50.40 2.00 2.00 6.82

2.2IndustronicDC/DC convertor -21EA48VDC5 16.00 80.00 80.00 272.97

2.3IndustronicDigital intercom Rack1EA48VDC480.10 4.80 4.80 16.38

2.4IndustronicBeacon 8EA24VDC241.40 33.60 268.80 NA

Total 1,868.16 5,457.25

ST-LQ

1PAGA System B

1.1IndustronicAccess Unit2EA48VDC480.20 9.60 19.20 65.51

1.2IndustronicExchange Board1EA5VDC52.00 10.00 10.00 34.12

1.3IndustronicIntercom station15EA48VDC480.10 4.80 72.00 245.67

1.4IndustronicDDSI15EA48VDC480.10 4.80 72.00 245.67

1.5IndustronicLine Monitoring ring2EA24VDC240.18 4.32 8.64 29.48

1.6IndustronicDigital Exchange 1EA5VDC51.00 5.00 5.00 17.06

1.7IndustronicLinecard Digital Intercom1EA5VDC50.40 2.00 2.00 6.82

1.8IndustronicPower supply control1EA3VDC31.00 3.00 3.00 10.24

1.9IndustronicAmplifier 4EA48VDC486.56 315.00 1,260.00 4,299.30

2IndustronicDC/DC convertor -11EA24VDC242.53 60.72 60.72 207.20

2.1IndustronicCPU1EA5VDC50.40 2.00 2.00 6.82

2.2IndustronicDC/DC convertor -21EA48VDC5 16.00 80.00 80.00 272.97

2.3IndustronicDigital intercom Rack1EA48VDC480.10 4.80 4.80 16.38

2.4IndustronicBeacon 8EA24VDC241.40 33.60 268.80 NA

Total 1,868.16 5,457.25

Appendix 2 ENERSYS Battery Performance Data

Vector InfoTech. LtdPage 10 of 10