Cable Test Voltage
Cable Test Voltage
(OP)
I would like to inquire what is the appropriate test voltage for a 6 year old 132kV underground power cable and a codes and standards that adhere to it?
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RE: Cable Test Voltage
RE: Cable Test Voltage
Specs
NETA MTS
IEEE 400
What type of cable? % insulation level?
RE: Cable Test Voltage
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RE: Cable Test Voltage
RE: Cable Test Voltage
RE: Cable Test Voltage
We do a ton of on line PD testing but not on 132kV in europe, however I do know someone who does.
RE: Cable Test Voltage
If there is no suspected problem, then taking it out to do either a HVac or PD (or both) test on it is really a waste of time. If you want to do something easy, you may want to measure PD activity by clamping a high frequency CT around the cable screen earth connection. This will give you an indication as to any problems in the sealing end or possibly joints in the cable. If this shows up anything, then perform an offline test.
If you do have a problem in a similar cable, then you really need to assess whether a high voltage test will determine if the the same problem exists in this cable or not. Adding a PD measurement to this would be valuable as well. Be aware here too that if PD activity is present at service volts, you may be seeing a quite a substantial problem.
PD tests have their limitations, in that the discharge pulses will only travel so far in the cable and still be detectable due to the attenuation of the cable impedance, so you may not "see" all the discharges in the cable. Again, you must know what you are looking for, and the limitations of the particular tests that you employ, to know whether it is a realistic test, or whether you will waste you money.
So if after you work out what you really need, you decide on a HV ac test, then another reference is the values in IEC 60840. This has figures for tests after installation of cables in this voltage range, and usually works on 1.7Uo for up to 60 minutes (ie about 132kV phase to ground). This figure obviously only applies if your cable was purchased to this standard, and as DPC says, have a chat with the manufacturer about it first. Also, you may want to decrease the test voltage due to the cable system being aged somewhat. Again, it really depends on what you are trying to achieve in your test.
ausphil
RE: Cable Test Voltage
What is the Test Voltage to be applied? Are there any other test to be conducted that we should be aware of?
RE: Cable Test Voltage
ausphil
RE: Cable Test Voltage