(h)  
Close this P6 panel circuit breaker:
 1) 6L12, CENTER BUS DC

 (2)
Remove electrical power if it is not necessary (AMM 24-22-00/201).

 S 865-025
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 (3)  S 865-026Set the switch on the relay adapter to OFF and remove the adapter. Install the isolation request relay and close the P6 panel.
 (4)  S 865-027Remove the meter and close the P11 panel.
 (5)  S 725-028Do a test of the ground handling relay as follows: (a) Set the multimeter to measure 115 volts AC. (b) Open the P34 panel and connect the meter to terminal A2 of the ground handling relay K101 and ground. (c) Supply external power to the ground handling bus (AMM 24-22-00/201). (d) Measure 115 |5 volts AC.
 (6)  S 865-029Remove electrical power if it is not necessary (AMM 24-22-00/201).
 (7)  S 865-030Remove the meter and close the P34 panel.
 (8)  S 725-031Do a test of the ground power transformer rectifier unit as follows: (a) Set the multimeter to measure 28 volts DC. (b) Open the P34 panel and connect the meter to the output terminals of the ground power TRU T103. (c) Supply external power to the ground handling bus (AMM 24-22-00/201). (d) Measure 28 |4 volts DC.
 (9)  S 865-032Remove electrical power if it is not necessary (AMM 24-22-00/201).
 S 865-033

 (10) Remove the meter and close the P34 panel.

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 S 725-034
 (11) Do a test of the left and right 28 volt AC autotransformers, as follows:
 (a)  
Set the multimeter to measure 28 volts AC.

 (b)  
Open the P70 panel and connect the meter to the LV terminal of the left autotransformer T123 and ground.

 (c)  
Supply external power to the left main AC bus
 (AMM 24-22-00/201).

 (d)  
Measure 28 |4 volts AC.

 (e)  
Push the EXT PWR switch on the M10063 electrical system control panel. Make sure the white ON light is off.

 (f)  
Remove the meter and close the P70 panel.

 (g)  
Open the P33 panel.

 (h)  
Connect the meter to the LV terminal of the right
 autotransformer T124 and ground.

 (i)  
Push the right BUS TIE switch on the M10063 panel to AUTO (in) position.

 (j)  
Push the left BUS TIE switch to the ISLN (out) position.

 (k)  
Push the EXT PWR switch, and make sure the white ON light is on.

 (l)  
Measure 28 |4 volts AC.

 (m)  
Push the EXT PWR switch, and make sure the white ON light goes off.

 (n)  
Push the left BUS TIE switch to the AUTO (in) position.

 S 865-035
 (12)
 Remove electrical power if it is not necessary (AMM 24-22-00/201).

 (13)
 Remove the meter and close the P33 panel.

 S 725-037

 (14)
 Do a test of the ground service 28 volt AC auto transformer, as follows:

 S 865-036
 (a)  Set the multimeter to measure 28 volts AC.
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 (b)  
Open the P34 panel, and connect the meter to the LV terminal of the ground service autotransformer T126 and ground.