Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Catawba Nuclear Station > 230KV Switchyard 125VDC System(EBH) > Flashcards

230KV Switchyard 125VDC System(EBH) Flashcards

1
Q

What is the purpose of the 230KV Switchyard 125VDC System(EBH)?

A

The 230KV Switchyard 125VDC System(EBH) provides an adequate and reliable source(non-safety related) of continuous DC power in the Switchyard for:

  1. All Relaying
  2. Controls
  3. Miscellaneous Equipment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the major components of the EBH System?

A
  1. The system is divided into 2 non-safety related trains. Each train contains a Battery, Battery Charger, and Distribution Center.
  2. One Standby Charger is located between the two trains.
  3. Each train is designed such that a single component failure will not result in a loss of protection for the equipment assigned to that train.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the purpose of the Battery Chargers?

A

The Battery Chargers rectify 480VAC to 125VDC to provide power to the loads and keep the batteries charged.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the designators for the Battery Chargers, where are they powered from, and what do they supply?

A

Train A:

  1. SYBC-1
  2. Powered from SPA
  3. Normally provides power to Distribution Center SYD-1

Train B:

  1. SYBC-2
  2. Powered from SPB
  3. Normally provides power to Distribution Center SYD-2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the capability of each Battery Charger?

A

Each Battery Charger:

  1. Capable of carrying the required loads and the 8 hour recharge of its battery.
  2. Can supply both trains simultaneously.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the Standby Battery Charger designator, when is it used, and what is it’s power supply?

A
  1. SYBC-S
  2. The Standby Battery Charger is placed in service to equalize batteries or when the normal chargers are out of service.
  3. Power is supplied from SPA.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the “Kirk-Key” interlock associated with the Standby Battery Charger?

A

The output breakers of the Standby Battery Charger have a “Kirk-Key” interlock that prevents closing both of them at the same time essentially cross-tying the distribution centers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the charger protective relaying?

A

When the voltage downstream of the DC output breaker is higher than predetermined setpoint the AC input and DC output breakers are tripped, WHEN THE CHARGER IS IN THE FLOAT CONDITION.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the purpose of the Batteries, and what are they rated for?

A
  1. The Batteries supply backup power to the distribution centers if power from the chargers is lost.
  2. Each Battery can carry both trains for 4 hours, AND still trip 8 PCBs at the end of that 4 hours.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the designators for the Batteries?

A

Train A

  1. SYB-1
  2. Normally is maintained in FLOAT on SYD-1

Train B

  1. SYB-2
  2. Normally is maintained in FLOAT on SYD-2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is “Cell Reversal” and when does it occur?

A
  1. Cell reversal can happen in batteries containing multiple cells in series when a cell’s voltage drops below the voltage of the battery bank. This happens under a heavy load condition, for long periods. The battery cell becomes a load on the battery causing the battery’s voltage to decrease at a higher rate.
  2. Cell reversal occurs at 80-85% of normal battery voltage. Once cell reversal occurs the cell can not be recovered.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do we prevent cell reversal?

A
  1. Minimize drain on the battery.
    A. Remove non-vital loads from the DC bus
    B. Placing AC portions of these systems on alternate power sources.
    C. Consulting Station Management for recommended loads to remove from a DC bus.
  2. Removing a battery from service when the battery’s voltage drops below 105VDC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is the most accurate indication of a Battery’s condition(voltage) under load?

A

The most accurate indication is taken at each individual battery cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What Panelboards are supplied by SYD-1?

A
  1. SYDP-A

2. SYDS-B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What Panelboards are supplied by SYD-2?

A
  1. SYDP-B

2. SYDS-A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What loads are supplied by SYDP-A and SYDP-B(125VDC Primary Panelboards)?

A
  1. Primary Relaying
  2. PCB Trip Coil #1 Circuits
  3. Unit 1 MOD Switches
  4. Breaker Failure Relaying
  5. Transfer Trip
  6. The Events Recorder
  7. DC Battery Test Panels
  8. Under Frequency Relaying
17
Q

What loads are supplied by SYDS-A and SYDS-B(125VDC Secondary Panelboards)?

A
  1. Secondary Relaying
  2. PCB Trip Coil #2 Circuits
  3. Unit 2 MOD Switches
  4. Breaker Failure Relaying
  5. Oscillographs
18
Q

What type of controls do the DC Test Panels contain?

A
  1. System Ground Monitoring
  2. System Ground Testing
  3. Battery Decay Testing
19
Q

What are the designators for the DC Test Panels, and where are they powered from?

A

Train A

  1. SYDC-1
  2. SYDP-A

Train B

  1. SYDC-1
  2. SYDP-B
20
Q

What are the indications of a ground on the EBH System?

A
  1. Ground alarms are received on the Switchyard Supervisory Alarm System and the Operator Aid Computer.
  2. The normally dimly lit lights above the Ground Test Pushbuttons will be bright.
  3. The Ground Test Pushbuttons when depressed will cause the voltmeter to indicate the magnitude of the ground.

No alarms are produced by depressing the Ground Test Pushbuttons

21
Q

Who depresses the Test Positive/Test Negative Volts to Ground and the Battery Decay Pushbuttons?

A

I&E personnel, not Operations.

22
Q

What alarms are provided at the DC Test Panel?

A
  1. “Distribution Center SYD-1 & SYD-2 Interlocked” alarm indicating the Tie Breakers are closed.
  2. “Charger SYBC-S Trouble” alarm.
23
Q

Where do we enter the Switchyard Relay House and what else is required after entering/before leaving the building?

A
  1. We enter the Switchyard Relay House through the door on the NORTH side.
  2. The alarm system on the NORTH wall must be disabled within 30 seconds of entering and enabled before leaving.
24
Q

What is the Switchyard Relay House entry process?

A
  1. Notify the Transmission Control Center of the intent to enter.
  2. Notify the Control Room of the intent to enter the house(OAC alarm is generated).
  3. Enter the relay house through the door on the NORTH side.
  4. Disable the alarm which is on the NORTH wall.
25
Q

What is the Switchyard Relay House exit process?

A
  1. Enable the alarm on the NORTH wall
  2. Exit the relay house within 30 seconds through the NORTH door.
  3. Notify the TCC and the Control Room.
26
Q

What are some applicable precautions and limitations associated with the EBH System?

A
  1. The DC Bus Tie Breakers normally remain open, unless equalize charging is in progress, or an abnormal lineup is required.
  2. Smoking, open flames, or activities that create sparks are NOT allowed in the battery area.
  3. When placing a charger in service the AC input breaker should be closed first.
  4. Battery chargers are normally in float.
  5. Without adequate ventilation in the battery areas toxic and explosive fumes will increase in concentration.

Catawba Nuclear Station (72 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions