after finding an unexpectedly high Zs on a shower, I narrowed it down to:
Zs at input of RCD (RCCB) is around 0.18 as would be expected but the Zs at the output of the RCD is 0.96! Both tests done with 3 lead low test on Megger MFT with 3 month calibration.
It is a split load board and both RCDs show similar results. Both pass standard TCD trip tests.
I haven't come across this before although some googling showed an MK article that said the electronics in an RCD can cause this.
It is a pain in the bum to have to bridge out the RCD to do the Zs tests in this case!?
Zs at input of RCD (RCCB) is around 0.18 as would be expected but the Zs at the output of the RCD is 0.96! Both tests done with 3 lead low test on Megger MFT with 3 month calibration.
It is a split load board and both RCDs show similar results. Both pass standard TCD trip tests.
I haven't come across this before although some googling showed an MK article that said the electronics in an RCD can cause this.
It is a pain in the bum to have to bridge out the RCD to do the Zs tests in this case!?
