Control Power 125VDC (PK)

Question 1

Where does PK system receive its power from ?

Answer 1

It receives it from a Class 480 MCC (PH)

Question 2

How many channels of control power is there ?

Answer 2

4 channels A,B,C,D

Question 3

What kind of equipment did each PK train have?

Answer 3

-Battery (each channel)
-Battery charger(each channel)
-Swing battery charger (Each Train)

Question 4

What do the ‘A’ & ‘B’ CHANNELS provide control power to?

Answer 4

-Train A & Train B
-vital instru. And control power for channels A &B RPS
-ESF system
-Diesel Generator A & B

Question 5

What do C & D channels provide instrument. & control power to ?

Answer 5

RPS & ESF systems and other safety loads

Question 6

What happens if AC or DC breaker is opened on battery charger ?

Answer 6

B01 will receive alarm in control room & plant computer (NOT SWING CHARGERS)

Question 7

What’re provided on 480 MCC for battery chargers to B,D,BD( Train B) ?

Answer 7

A disconnect switch that will isolate from control room in case of a control room fire

Question 8

What is used to prevent moisture in the battery chargers ?

Answer 8

Space heaters controlled by thermostats

Question 9

What will an operator have to do to investigate a an alarm on battery charger ?

Answer 9

Operator will have to open cabinet and investigate the LED indications

Question 10

How do you swap class battery chargers ?

Answer 10

-Remove in service battery charger and place oncoming battery charger.

-Class battery chargers should NOT be place in parallel

Question 11

What’re the purpose of the Class batteries ?

Answer 11

2 hours of DC power to class loads during a LOCA,LOP, or design basis event

Question 12

During a station blackout what will happen for Class loads that are powered from PK?

Answer 12

First hour Class batteries will power class loads, then once SBOGS are in service A train battery chargers will be loaded on

Question 13

How does PK interface with PN system ?

Answer 13

PK send 125VDC power through inverter and changes it to 120VAC to supply PN instrument power

Question 14

What indication do you look for on an under voltage on a class control center?

Answer 14

A local white light indicator and a alarm in control room

-Alarm will self reset when conditions clear

Question 15

What indication do you look for on a ground bus condition of a control center ?

Answer 15

-White light will illuminate and alarm will be on in control room

-The “ground reset” button will reset alarm and indication

Question 16

What will happen if battery breaker is closed, while racking screw cover interlock is open ?

Answer 16

The battery breaker will trip due to cover being open

Question 17

Which channels do the battery breakers have transfer switch on ?

Answer 17

Channels A,B,C battery breaker

Question 18

How does PKA system interface with diesel generators ?

Answer 18

Provides control power and field flashing power

Question 19

How does PK interface with AF?

Answer 19

Supplies control power to MOV & Electronic Governor Regulator

Question 20

How does PK interface with Oily Waste(OW)?

Answer 20

OW provides drains for each battery room for 1 of 2 neutralizing sumps (One per train)

Question 21

How does PK interface with SG?

Answer 21

Provides control power to MSIVS logic cabinet

Question 22

How does PK interface with Safety Injection?

Answer 22

Supplies control power through inverter to motor operated Shutdown Cooling Containment Iso. Valves

Question 23

How does PK interface with Containment isolation ?

Answer 23

Provide control power to containment isolation valves