Stator and Isophase Cooling

Question 1

State the Purpose and Capabilities of the Stator Cooling System, Isophase Bus Cooling System, and The Collector Housing Cooling Unit.

Answer 1

The Stator Cooling System provides cooling for the main generator stator windings, terminal
bushings, the excitation rectifiers and the connection rings.

The Isophase Bus Cooling System provides cooling for the isolated phase buses that connect the generator output to the Main Power Transformer.

The Collector Housing Cooling Unit provides cooling to the main generator collector housing.

Question 2

Unit 1 is at 100% power with all systems in a normal lineup.
Stator Cooling Pump CEN-P01A is running, CEN-P01B is in standby.
The feeder breaker for CEN-P01A opens on ground fault and trips the 86 relay.
One minute later, with no operator action, what is the status of CEN-P01B?
A. Not running. The pump can only be started by manual action in the control room.
B. Running. The pump automatically started because of the 86 lockout.
C. Running. The pump automatically started on low discharge flow.
D. Running. The pump automatically started on low discharge pressure.

Answer 2

D

Question 3

The Stator Cooling Water flows through the Stator Cooling Water Heat Exchangers in \_\_\_(1)\_\_\_.  Turbine Cooling water flows through the Stator Cooling Water Heat Exchangers in \_\_\_(2)\_\_\_.
A.  (1) series; (2) series
B.  (1) series; (2) parallel
C.  (1) parallel; (2) series
D.  (1) parallel; (2) parallel

Answer 3

B

Question 4

What is the cooling water for the Isophase Bus Duct air coolers?
A.  Nuclear Cooling Water (NC)
B.  Normal Chilled Water (WC)
C.  Stator Cooling Water (CE)
D.  Turbine Cooling Water (TC)

Answer 4

D

Question 5

If the normally running isophase bus cooling air blower trips, the standby unit ___(1)___. With no isophase bus cooling air blower running, ___(2)___.
A. (1) will auto start; (2) the generator must be tripped immediately
B. (1) will auto start; (2) the generator load must be reduced in 30 minutes
C. (1) must be manually started; (2) the generator must be tripped immediately
D. (1) must be manually started; (2) the generator load must be reduced in 30 minutes

Answer 5

D

Question 6

Stator Cooling Water Pump P01A and P01B are supplied power by…

Answer 6

Non-Class IE 480 VAC NGN-L15 and L14