What is the proper way to connect a GPU to the aircraft

[JAR48]

what is the proper way to connect GPU to the aircraft 

[Fly Boomer]

18 minutes ago, JAR48 said:

what is the proper way to connect GPU to the aircraft 

https://www.aircraftspruce.com/catalog/elpages/jumpercables.php

[JAR48]

there are two different procedures out there; one is to turn the GPU on, let it stabilize, then connect the cable to the aircraft.  The other is to connect the cable to the aircraft with the unit off, then turn it on after the unit is connected.  Anyone know which one is correct?

[Rick Junkin]

31 minutes ago, JAR48 said:

there are two different procedures out there; one is to turn the GPU on, let it stabilize, then connect the cable to the aircraft.  The other is to connect the cable to the aircraft with the unit off, then turn it on after the unit is connected.  Anyone know which one is correct?

I turn the GPU on and verify stable power first, and then connect it to the airplane. That’s what the White Lightning GPU owner’s manual says to do, and it’s how we did it on military jets. 

[Fly Boomer]

1 hour ago, JAR48 said:

there are two different procedures out there; one is to turn the GPU on, let it stabilize, then connect the cable to the aircraft.  The other is to connect the cable to the aircraft with the unit off, then turn it on after the unit is connected.  Anyone know which one is correct?

That NATO connector is designed to be plugged in “hot”.  The larger positive and negative pins make good contact before the smaller pin energizes the relay connecting the juice to your airplane.