RCD tripping... something odd here....

[Lurch]

scheme registered or not Zs does not indeed come into play when functional testing the rcd but as lurch says when testing Zs the rcds very often trip.headbangheadbang

Well not quite, as I've said in a thread on the subject, in circuits with a highish Zs and low rated MCB's, such as an upstairs lighting circuit, the MCB will often trip when testing Zs at 25A.

 

[steptoe]

scheme registered or not Zs does not indeed come into play when functional testing the rcd but as lurch says when testing Zs the rcds very often trip.headbangheadbang

as I said , so why is OP involving the Zs on his test?

test the RCD at the CU using 3lead test.

Zs proves the circuit is safe(in a manner of speaking, nothing to do with RCD operation)

BTW, Im sure functional testing is simply pushing button T .

 

[niceguy]

I always test the RCD's at the CU.

Silly not to when it saves going backwards and forwards to the CU if you dont have autotest.

Also, i very rarely have problems with RCD's tripping when performing a Zs test.

Occasionally a 6A MCB will go, but thats only when using the cheap own brand shyte CU's.

 

[kme]

BTW, Im sure functional testing is simply pushing button T .

You`d be correct bud

 

[bengie]

I always test the RCD's at the CU.Silly not to when it saves going backwards and forwards to the CU if you dont have autotest.

Also, i very rarely have problems with RCD's tripping when performing a Zs test.

Occasionally a 6A MCB will go, but thats only when using the cheap own brand shyte CU's.

we get the problem all the time with mcb's and rcbo's, its a bloody nightmare and we use contactum and wylex only so should be decent.

 

[PIP IOM]

Had same issue some weeks ago with my Megger 1502, manufacturer told me the repair/upgrade was not cost effective so bought Megger 1553 (guaranteed no trip) and to date all OK. CEF on the Iisland

 

[gselectrical]

test the RCD at the consumer unit.as has been said, your R1R2 test and your Zs is proof that the RCD will function inside the parameters allowed in case of a fault.

test the RCD, NOT the circuit.

Agreed;\

 

[steptoe]

Had same issue some weeks ago with my Megger 1502, manufacturer told me the repair/upgrade was not cost effective so bought Megger 1553 (guaranteed no trip) and to date all OK. CEF on the Iisland

 

[PIP IOM]

Love the Megger, Love the rock (22 yrs), CEF are the best of a bad bunch and will deliver island - wide. I was on the first power station 21 yrs ago, came to the island after 10 yrs on the other rock (Jersey)