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Has anybody HI-POT a PLC Control Panel?

Has anybody HI-POT a PLC Control Panel?

Has anybody HI-POT a PLC Control Panel?

One of my clients want me to Hi-POT my PLC Control Panel per their specification.
I have never been requested this before on a PLC Panel. I'm pretty sure a Hi-POT
will damage Electronic Equipment in the panel.

Has Anyone done this before? Do you have to unterminate every wire end to end
to do a Hi-Pot test?

RE: Has anybody HI-POT a PLC Control Panel?

Groan.. idiots abound.

You will have to analyze your entire PLC panel for those things that connect to line voltage gear and after noting the actual specs of those parts of the setup, Hi-POT just them.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Has anybody HI-POT a PLC Control Panel?

Hi R-Roc,
I suspect that they want you to megger, and not hi-pot, the wiring portion of your control system. Even with meggering, you must ensure that anything with an electronic component is completely isolated. Anything not isolated will be almost certainly be toast.
Did you client provide the "hi-pot" potential to which the test is to be conducted to? (ie 300V, 600V, 25kV).

"I have not failed. I've just found 10,000 ways that won't work." Thomas Alva Edison (1847-1931)

RE: Has anybody HI-POT a PLC Control Panel?


See attached specification. It silent on voltage range.
I know 14 AWG wire insulation in my panel is only rated for 600V and the Belden cable I have is only rated for 300V.
I might be just megger each and every wire in my panel. If I had known this sooner I would have megger/hi-pot the cable
reel and call that good. To many wires to de-termaintate and re-terminate again.


RE: Has anybody HI-POT a PLC Control Panel?

Hi R_Roc,
I would suggest that a 300V megger would be more than sufficient on 300/600V wiring. You will need to disconnect the field wiring from the I/O cards / power-supplies / etc though. I assume that your I/O cards have some means of bulk disconnect (like a wiring-arm or plug), correct?

"I have not failed. I've just found 10,000 ways that won't work." Thomas Alva Edison (1847-1931)

RE: Has anybody HI-POT a PLC Control Panel?

I wish my I/O cards did. My project called for the 1794 Flex I/O family of module.
Luckily I only have 4 modules.

Do you know what the ANSI and Nema Standard requirement is for meggering/over-potential test in my case?

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