×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Hi-Pot Testing Control Panels

Hi-Pot Testing Control Panels

Hi-Pot Testing Control Panels

(OP)
I have some questions regarding hi-pot testing of equipment.
We manufacture automation equipment and are looking in to hi-pot testing the control panels and control system.  My question is what needs to be tested...
The control panels consist of contactors, relays, disconnects, inverters, plc's etc... most of which have been hi-pot tested by the manufacturer.  So do i just test all of the remote wiring? and how do i do that without damaging equipment...

any help is greatly appreciated

RE: Hi-Pot Testing Control Panels

Is this for some agency listing?  If so, then you would just have to become familiar enough with the applicable standard, etc...

The most common hi-potting scenario with which I am familiar is hi-potting between all the wires tied together and the control panels.  If all the wires are tied together, there is no reasonable way to destroy a given piece of equipment.  Any resulting breakdown will either a result of nicked wire insulation, poor design of a given piece of equipment (which should have been handled by the manufacturer of the equipment), or careless construction of your automation equipment...

RE: Hi-Pot Testing Control Panels

...but you don't normally hi-pot test a panel with the active electronics (inverters, PLCs) installed.  Usually, it is just the plain old panel itself being tested (wires, connectors, maybe switches) - nothing low voltage.

RE: Hi-Pot Testing Control Panels

(OP)
So for practical purposes, I would test all the wires before they are terminated?  What we do is build and wire the backplate's for the panels on a bench, and then install them into the cabinets when complete.  We then do the remote wiring and terminations.  But by what you are saying, we dont need to test the low voltage(120vac/24vac) control wiring, just the high voltage (480/600vac)?

As far as agency listing, we would like to build the machiney with CE compliance.  As well, the hi-pot testing has been recommended as a good manufacturing procedure by an outside agency.  To be honest, we've never had any problems without the testing, but i guess it is a good idea to do..

RE: Hi-Pot Testing Control Panels

Yes, that is true...back to the question regarding agency listing.

During my days working for a custom automated test equipment outfit we never had any kind of agency listing and we never hipotted anything.  Amongst many other things, our equipment was responsible for controlling a hi-pot tester and was also responsible for connecting the output of the hi-pot tester to the DUT, but we never hi-potted our equipment (I suppose you could say part of our equipment was hi-potted every time a product went down the assembly line...).

RE: Hi-Pot Testing Control Panels

Your panel should be tested in its most fully configured, final stage of assembly. Typically, this is the point where your product is next going to boxed/shipped/warehoused.

The purpose of the hi-pot test is to find a weak link in the insulation caused by inadequate materials or poor/damaged construction.

It's also important to ramp up/ramp down your test potential voltage slowly so that you do not inadvertantly punch a hole in the insulation (your test standard should give some guidelines on volts/sec).

Your test should encompass all wiring/components where primary mains AC is typically present during normal operation, which would include 120 VAC and above.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources