LOT 201.30 Offsite Electrical

Question 1

• LOT 201.30 Offsite Electrical*
• • *

Which switchyard lines are not allowed to be counted toward tech specs?

Answer 1

• *Blessing 44 Line**
• Limited capability to provide required voltage*
• *138 KV Blessing Line**
• Lines run below other lines*
• *HILLJE 64 Line**
• Lines run below other lines*
• *HILLJE 44 Line**
• Lines run below other lines*

Question 2

• LOT 201.30 Offsite Electrical*
• • *

What provides control power for the Main Generator Breaker?

Answer 2

TB 250VDC 1A

• Note:*
• Control power for the 13.8 kV breakers will come from either 125VDC Bus 1A or 1B. (Non-Class 125VDC busses)*

Question 3

• LOT 201.30 Offsite Electrical*
• • *

What will happen in the switchyard if a fault occurs on the standby transformer?

Answer 3

• Unit 1:*
• *All North Side breakers will trip**
• Unit 2:*
• *All South Side breakers will trip**

Question 4

• LOT 201.30 Offsite Electrical*
• • *

What powers the 138 kV Emergency Transformer?

Answer 4

138 kV Blessing Line

Steps down voltage from 138 kV to 13.8 kV.

Can supply 1 ESF bus in each plant.

Note:
CP010 houses handswitch controls for the Emergency Transformer motor operated disconnect and the 13.8 kV feeder breaker to bus 1(2)K.

Question 5

• LOT 201.30 Offsite Electrical*
• • *

What voltages are present on each side of the standby transformers?

Answer 5

345 kV / 13.8 kV

• Note:*
• CP010 houses handswitch controls for the 13.8 kV feeder breakers.*

Question 6

• LOT 201.30 Offsite Electrical*
• • *

What voltages are present on each side of the UAT?

Answer 6

25 kV / 13.8 kV

• Note:*
• CP010 houses handswitch controls for the 13.8 kV feeder breakers.*

Question 7

• LOT 201.30 Offsite Electrical*
• • *

Which 13.8 kV switchgears are normally powered from the standby transformers while at power?

Answer 7

1G STBY Bus

2G STBY Bus

Loss of North Bus starts SDG 12

Loss of South Bus starts SDG 22

Question 8

• LOT 201.30 Offsite Electrical*
• • *

What is the purpose of a shunt reactor?

Answer 8

Compensate for line capacitance which can cause an elevated voltage during light load conditions.

Question 9

• LOT 201.30 Offsite Electrical*
• • *

Where are the Unit 1 and Unit 2 standby transfomers powered from?

Answer 9

• Unit 1:*
• *North Bus**
• Unit 2:*
• *South Bus**

Question 10

• LOT 201.30 Offsite Electrical*
• • *

Which switchyard breakers can be operated from the control room?

Answer 10

• Unit 1:*
• *Y510 / Y520**
• Unit 2:*
• *Y590 / Y600**

Isolates the Main Transformer from the switchyard.

• Note:*
• Visual Indication on CP007 AND CP010. Operable from CP007 ONLY.*

Question 11

• LOT 201.30 Offsite Electrical*
• • *

What voltages are present on each side of the Main Transformer?

Answer 11

25 kV / 345 kV

• Note:*
• CP007 houses handswitch controls for the Main Generator Circuit Breaker and the applicable unit switchyard pneumatic circuit breakers.*

Question 12

• LOT 201.30 Offsite Electrical*
• • *

Procedurally, what is the current rating of the standby transformer windings?

Answer 12

1621 Amps / Winding

Equivalent to 2 Aux Busses and all 6 ESF busses fully loaded.