Should we test connector @rated voltage AND current (8kv, 200A)?
Should we test connector @rated voltage AND current (8kv, 200A)?
(OP)
Hi,
I'm a Mechanical Engineer at a company where make feedthru connector systems to run 3-phase submersible pump motors in oil wells. Our standard product is rated at 5kv and up to 210A. Typically we do dc hi-pot testing (1 minute @24kvdc, 5 microamps max leak) to validate the voltage rating, and also low voltage, no load, closed circuit heat rise testing to validate the current rating. With new upcoming applications requiring 8kv we are now concerned with PD and we're in the process of purchasing partial discharge test equipment. When that comes we'll need to figure out some acceptable initiation and extinction values, but my question right now is regarding a proposal to outsource full load testing. Do you guys think it is of value to test the connector system with a load so that it's at rated current and voltage simultaniously or is that no different than testing voltage and current independently as we currently do?
I'm a Mechanical Engineer at a company where make feedthru connector systems to run 3-phase submersible pump motors in oil wells. Our standard product is rated at 5kv and up to 210A. Typically we do dc hi-pot testing (1 minute @24kvdc, 5 microamps max leak) to validate the voltage rating, and also low voltage, no load, closed circuit heat rise testing to validate the current rating. With new upcoming applications requiring 8kv we are now concerned with PD and we're in the process of purchasing partial discharge test equipment. When that comes we'll need to figure out some acceptable initiation and extinction values, but my question right now is regarding a proposal to outsource full load testing. Do you guys think it is of value to test the connector system with a load so that it's at rated current and voltage simultaniously or is that no different than testing voltage and current independently as we currently do?





RE: Should we test connector @rated voltage AND current (8kv, 200A)?
If you really want or need to do a combined high current / high voltage test then I don't think it would be unreasonable to drive an HV current transformer in reverse as the source of test current and float the CT 'primary' (high current side) at whatever proof voltage you desired. That way you're using relatively low energy sources to develop high current and high voltage without needing an MV substation and a fairly large load bank to achieve it. That said, it would be a test rig with enormous potential to kill the unwary and would have to be very carefully designed to ensure safety.
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If we learn from our mistakes I'm getting a great education!
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
That's a test we could run for less cost than a full load test.
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
I might be overlooking something obvious, but I can't think what. No doubt one of our peers will point it out to me soon!
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If we learn from our mistakes I'm getting a great education!
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
It seems more of a power question than a motor question to me though.
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RE: Should we test connector @rated voltage AND current (8kv, 200A)?
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
It probably won't make a difference in your instance but inadvertent poor connections may perform differently depending on whether the heat is applied externally or internally.
BTW, Using CTs to test at high current while floating at high voltage may not be much more hazardous than testing at high voltage.
And, testing at a full 200 Amps and 8kV with a load bank may end up with the kWHr charges being a major portion of the testing expense.
Bill
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"Why not the best?"
Jimmy Carter
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
I agree Bill, but the electricity bill will be much lower, say a 10kW load compared to 1.6MW. Lower arc flash hazard too.
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If we learn from our mistakes I'm getting a great education!
RE: Should we test connector @rated voltage AND current (8kv, 200A)?
Yous
Bill
Bill
--------------------
"Why not the best?"
Jimmy Carter