Busbar Insulation Resistance Testing

[lannoy]

I am re-utilising previously idle and dismantled 11 & 33kV switchgear. Will conducting Insulation Resitance (IR) test at 500V give me an indication of the likely condition of the busbar insulation, if so what value would be an acceptable IR reading? I would of thought >100 Mohm

I will of course be conducting full pressure and partial discharge testing of the switchgear when assembled.

 

[Jerry123]

If you test at 500Vdc your insulation resistance should be better than 2000megohms. 500V may not stress the insulaton enough to give a valid IR.

You should test the gear at a minimum of 2500Vdc for 15KV rated switch gear. I don't have the book in front of me right now but I think that the minimum insulation resistince for 15KV gear tested at 2.5KVdc is 500megohms. I will look it up tommarow an let you know.

 

[alehman]

For accptance of new gear, the National Electrical Testing Association recommends the following: 5kV-15kV gear should be tested at 2.5kVDC with a minimum resistance of 5000Mohms. For 35kV gear, test at 15kVDC with a minimum resistance of 100,000Mohms.