DC testing voltages
DC testing voltages
(OP)
When doing DC hipot tests, what value of a DC voltage do you use relative to the rated voltage of a cable? Like for 11kV rated cables (AC) what value of DC voltage can i use? What does the BS standard say about this?






RE: DC testing voltages
Remember that hi-pot testing is potentially destructive (pass/fail).
RE: DC testing voltages
RE: DC testing voltages
RE: DC testing voltages
For ANSI regions, I agree with wareagle’s numbers that are consistent with {US} ICEA standards, but only for new, yet-to-be-energized cable. Again, for ANSI practices, IEEE std 400 was overhauled in 2001 and may be worth a careful read.
RE: DC testing voltages
For normal maintenance of cable that has already been placed in service, I would not recommend testing the cable above its rated value unless you have made provisions to pull new cable in the event of a failure.
Since I work for a service company we ALWAYS have the customer tell us at what value to hipot exsisting cable.
As stated hipot testing is a destructive test.
RE: DC testing voltages
RE: DC testing voltages
RE: DC testing voltages
A HIPOT may cover you as far as you local standards but, it is a fairly useless test. The only information one knows from a successful HIPOT test is that the cable survived the overvoltage! The cable could still fail after you put the cable back in service. You must measure the cable's response during the voltage application to predict future performance.
The best recommendation for PILC cable.
1. Disconnect cable from the load
2. Perform a 5kV 'megger' test (Doble or tan delta test would be better)
3. Perform a 60 Hz PD test up to 1.7-2.0Uo.
PILC cable have a proven track record if they are built correctly. They can last 80+ years. The problem today is that there are very few contractor who know how to properly build PILC cables. The job requires a true artist with knowledge of hot oil tests (for terminations and joints)and nitrogen pressure test (for joints).
-Cheers