Measurement in cable of 15kv with flexible current sensor.

[Guilhermebr]

Anyone did current measurement with flex sensor in 15 kv cables? I am problems in measurement.

I opened the shield in the cable disconnect to the ground, but de current have oscilation.

I am use the dranetz px5 with 3 dranflex.

GS

 

[7anoter4]

Sorry. I never used dranetz px5 [with 3 dranflex]. That means the cable is 3 core cable and you have 1 dranflex per phase. This device measure the current flowing through conductor so the shield both ends has to be insulated.
What kind of test do you and what the current level is?.
You may have an oscillating capacitive current -it depends on cable length.
The instruction book does not indicate how to proceed in different cases.

http://www.dranetz.com/wp-content/uploads/2017/04/Dranetz-PX5-Family-Current-Probes-Brochure.pdf

 

[Guilhermebr]

Hi.


I am using 1 dranflex per phase. The cable have around 100 meters in 12k.
I am measurements stator current. It is dfig wind generator 3MW. The cliente say that did measurement in the same cables and same point with normal cts, and opened shield in ends of the cables and Ok, but with my rogowisk sensores dranflex I have problems. The manual px5 didnot show me about this case.

Attachment local mesurement Picture.


GS

 

[7anoter4]

It is difficult to see the connections. In my opinion the dranflex loop on the cable it seems to be loose and it will catch electromagnetic fields from vicinity. Do it more tight and avoid to be close to other power cables. I think a clamp-on probe will be less sensible to noise.