Oral Prep Elec PWR

Question 1

What does the DC GEN 1/2 Fault light indicate?

Answer 1

Fault LT extinguish above 61.5% NH if operating Normal
.>61.5% NH, gen not functioning properly / triggered by GCU
Auto reset by GCU if underspeed situation

Question 2

EXT PWR PB
What does the AVAIL light indicate?

Answer 2

Proper
Voltage / Current / Polarity

Question 3

DC SVC/UTLY BUS
SHED light

Answer 3

One of the DV SVCE / UTLY 1 and 2 busses is shed

Question 4

DC SVC/UTLY BUS
OFF light

Answer 4

All the DC SVCE BUS/ UTLY 1 AND 2 BUSSES ARE SHED

Question 5

BTC GAURDED SWITCH
GREEN FLOW BAR?

Answer 5

BPCU CONTROLS BTC OPERATION/ESTABLISHES PRIORITY
EXT PWR, HOTEL MODE, OR SINGLE GEN OPS
(BTC IS CLOSED)

Question 6

BTC GAURDED SWITCH
ISOL (BLUE)

Answer 6

BTC OPENED (PRESS IN)
BTR (BUS TIE RELAY) LOCKED OPEN (tie between ac busses)

Question 7

What type of batteries are used?

Answer 7

24v Nicad Battery

Question 8

How many batteries do we have?

Answer 8

2
MAIN
EMERGENCY

Question 9

WHAT ARE THE AMPS TO THE BATTERIES?
MAIN? EMERGENCY?

Answer 9

MAIN 43 AMPS
EMERGENCY 17 AMPS

Question 10

WHAT CAUSES BATT CHARGE FAULT?

Answer 10

THERMAL RUNAWAY
BUS VOLTAGE <25V
BAT SWITCH IN OVRD
START SEQUENCE

Question 11

WHAT HAPPENS WHEN BAT SWITCH IS IN ON POSITION?

Answer 11

STANDBY BUSES SUPPLIED BY HOT MAIN BATTERY BUS
IF GPU CONNECTED/GEN 1/2 ONLINE, THEN DC STDBY BUS IS SUPPLIED BY THE HOT EMER BUS AND AC STDBY BUS IS SUPPLIED BY DC BUS 1

Question 12

WHAT HAPPENS WHEN BAT SWITCH IS IN OFF POSTION?

Answer 12

ESS BUS, DC STBY BUS AND INV1 ARE ISOLATED FROM HOT MAIN BATT BUS
DC EMER BUS IS ISOLATED FROM HOT EMER BAT BUS

Question 13

WHAT HAPPENS WHEN BAT SWITCH IS IN OVERRIDE?

Answer 13

ENSURES BASIC MODE OPERATION BY OVERRIDING ALL OTHER PROTECTIONS

Question 14

WHAT IS DIFFERENCE BETWEEN
BASIC MODE?
EXT PWR?
GEN MODE?

Answer 14

BASIC - BATT SWITCH ON AND NO OTHER SOURCES OF PWR CONNECTED
EXT PWR - BPCU PRIOTITIZES GPU OVER OTHER SOURCES OF POWER
GEN MODE - BOTH GENS RUNNING NORMALLY

Question 15

WHAT DOES UND/V LIGHT MEAN?

Answer 15

DC STBY BUS VOLT <19.5V

Question 16

WHY IS 19.5V SO IMPORTANT?

Answer 16

THE INVERTERS NEED AT LEAST 18V MINIMUM

Question 17

WHEN PRESSING GAURDED STBY BUS, WHAT WOULD YOU SEE?

Answer 17

DC STBY BUS IS NOW POWERED BY HOT EMER BAT BUS
UND/V LIGHT EXTINGUISHES
OVRD LIGHT ILLUMINATES
LEFT AMBER ARROW FROM EMER BUS

Question 18

WHAT BUSES IS TRU POWERING?

Answer 18

EMER BUS
ESS BUS
DC STBY BUS
INV 1
AC STBY BUS

Question 19

HOW MANY AC BUSES? WHAT ARE THEY?

Answer 19

3
AC BUS 1
AC BUS 2
AC STBY BUSS

Question 20

WHAT IS THE OUTPUT OF INVERTERS?

Answer 20

26V/115V

Question 21

WHAT IS THE OUTPUT OF THE ACW GENERATOR

Answer 21

115V TO 200V

Question 22

WHAT IS THE OUTPUT OF THE TRU?

Answer 22

28V

Question 23

3 REASONS BTC WILL BE CLOSED?

Answer 23

EXT PWR ON
HOTEL MODE
SINGLE DC GEN OPS