Voltage Withstand Test Without Ground

[fifty60]

How would a dialectric test be performed on a jack assembly that does not have any provisions for a ground? The jack assembly consists of 3 prongs encased in an insulating plastic material. I would typically approach this as test each line independently to the ground prong, and then tie all the lines together and dialectric test them all to the ground prong. Without a ground prong, or any kind ground present on the assembly, how can a dialectric test be performed?

Would I only be able to test between individual line conductors? For example, instead of applying 1500 VAC between L1 and Ground, I would just apply 1500VAC between L1 and L2, and check for any current coming back on L2?

 

[petersonra]

I would test them L-L

 

[Ingenieur]

why not ground one prong and apply voltage individually to the others
rotate and do each as a ground
???

 

[Nuber]

Are there any other items near the cable that are bonding to the electrical system ground? Test each pin to an accessible "grounded" point. You should complete 6 tests this way including the L-L previously discussed.

The L-L test verifies that there are no line to line shorts in the cable. The pin to ground test ensures that there will be no ground fault path from inside the cable to the electrical system ground.

We used to do this all the time in the old Navy days, but a steel hull always has an easily accessible "ground" point for reference.