(4)  
Inspect feeder terminations at the generator for sign of overheating and arcing.

 (a) Repair terminations if any problems are found.

 (5)  
Check ground side feeders on generator to ENG GND lug for continuity.

 (a)  Repair wiring and terminations if any problems are found.

 (6)  
If no problems are found, apply electrical power (AMM 24-22-00/201).

 (7)  
Measure the voltage drop accross the contacts of the generator circuit breaker (C801 - LEFT, C802 - RIGHT) and the transfer relay (R3 - XFR BUS 1, R4 - XFR BUS 2) for each phase with load applied.

 (8)  
If there is any significant voltage drop (greater than 1V AC) replace the GCB or Transfer relay.

 NOTE: The load circuit breaker may trip open when trying to apply
____ the load. If this happens replace GCB and transfer relay.
 (9)  
Measure the output voltage at the generator terminals with load applied. If the voltage is outside the limit of 115V AC + or - 5V on any phase, replace the generator (AMM 24-11-11/401).

 (10)
 Remove electrical power if it is no longer necessary (AMM 24-22-00/201).

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A
737-300/400/500MAINTENANCE MANUAL
 AC GENERATION SYSTEM - ADJUSTMENT/TEST
______________________________________
 1.  General_______
 A. This is a test of the AC generation system and its components.
 B. This procedure contains the following tasks.
 (1)  
AC Generation System Test

 (2)  
Generator Phase Sequence Test

 (3)  
Bus Transfer Interlock Test

 (4)  
On-Wing VSCF Voltage Regulator Adjustment

 TASK 24-21-00-735-001
 2.  AC Generation System Test_________________________
 A. General
 (1)  
This is a test of the engine-driven generators, APU generator, and external power. You will do tests of the generators, the main power breakers, and the ac buses with electrical loads. The electrical loads that you use are the lights, galleys, air conditioning, fuel boost pumps, and hydraulic pumps.

 (2)  
It is necessary to operate the engines and the APU when you do this test. If a generator goes off-line or a power transfer does not occur, do the trouble-shooting of the generator, GCU, and transfer bus relays (Ref 24-21-00/101).

 (3)  
To get accurate results from this test:

 (a)  
Make sure that all meters display and operate correctly.

 (b)  
The press-to-test lights must operate correctly.

 B.
References

 (1)  
AMM 24-21-00/101, AC Generation

 (2)  
AMM 49-11-00/201, APU Power Plant

 (3)  
AMM 71-00-00/201, Power Plant

 C.
Access

 (1)  
Location Zones 101 Left Control Cabin - P5 Forward Overhead Panel 102 Right Control Cabin - P6 Main Power Distribution Panel 202 Lower Nose Compartment

 (2)  
Access Panels 1101R External Power Receptacle Door 1103L Forward Access Door - E-11 Landing Gear Logic Shelf

 D.
Prepare for the Test

 S 865-002
 (1)  Make sure that the STANDBY POWER switch on the P5-5 panel is in the AUTO position.
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737-300/400/500MAINTENANCE MANUAL
 S 865-003
 (2)  
Make sure that the BUS TRANS switch on the P5-4 panel is in the AUTO position.

 S 865-004

 (3)  
Make sure that these circuit breakers are closed:

 (a)  
J9 battery shield panel
 1) C142, BATTERY CHARGER
 2) C798, AUX POWER UNIT START

 (b)  
P6-2 panel
 1) C362, FLIGHT CONTROLS - SHUTOFF VALVES - STBY RUD