brand new RCD don't work

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

danny7299

Well-known member
Joined
Apr 6, 2008
Messages
880
Reaction score
0
Location
Leicestershire
I have been installing a new CU today... (I know its Sunday!)

And when I had put it all together and powered up, the RCD kept tripping , wouldn

 
Danny if it trips on the 50% test with no load connected then it must be defective.

You could have had standing Earth leakage on the installation you worked on today which amounted to 15mA ...or abit more.this would trip the faulty rcd but the replacement may just be holding [ Less than about 24mA in total ]

.If not the case and your IR tests proved it then maybe dodgy connections at the consumer unit.

 
Not Hager generally used to get main problems Wylex but I replaced one on some street lighting a few months back it had been in a few years and kept tripping out so tested installaton which was very good so concluded it was the RCD changed and have not been called back. I have fitted a lot of Hager Rcbo's recently they tripped ok on 1x test but where failing on 5 x test but I think it may have been my old tester a di-log. My Fluke is away being repaired more than its here so have gone back to my Megger cm500 this works well apart from the low current loop test which can be out considerably. When I get my Fluke back I am going to send it away to hopefully get it adjusted.

Batty

 
When I was fault finding there are 2 boards in the property and I moved and changed the RCD around and it was only that RCD that was doggy...

Just slightly annoyed as I have to go back to job now!!!

ohh well, win some, lose some

 
The fact that you tested and found the fault means that yet again a proper electrician has helped to save a life.

 
I have had the opposite problem a few years back brand new RCD, (can't remember make) would NOT tip at all!!! only with test button..

Got it replaced FOC by supplier.

Anyway since then I ALWAYS test RCDS before going to site...

just stick a bit of flex off my snap block power it up stand-alone on my garage bench... then quick trip test!

I have also had a main switch that was only making one half...

Live came on, but neutral leg stayed open circuit..

so I also stick my continuity buzzer across all main isolators & MCB's before going to a CU change..

It don't take long but can save wasted time....

the only other solution IMHO is as Andy C says..

carry duplicate stock in-case of commissioning failures.

:| ;)

 
I once installed a 100mA time-delayed RCD in a thatched cottage as additional protection against setting the roof alight, feeling pleased with myself I pressed the test button and watched smoke pour out of it, shortly followed by flames...

Luckily I was able to pull the cut-out & the flames went out before they even scorched the enclosure.

 
I once installed a 100mA time-delayed RCD in a thatched cottage as additional protection against setting the roof alight, feeling pleased with myself I pressed the test button and watched smoke pour out of it, shortly followed by flames...Luckily I was able to pull the cut-out & the flames went out before they even scorched the enclosure.
:eek: :O:|

bob

 
I once installed a 100mA time-delayed RCD in a thatched cottage as additional protection against setting the roof alight, feeling pleased with myself I pressed the test button and watched smoke pour out of it, shortly followed by flames...Luckily I was able to pull the cut-out & the flames went out before they even scorched the enclosure.
I hate it when they do that.

:|

 
Top