Memera 2000 RCD Question (A100HE)

1strangefish · Mar 12, 2013

Hi Guys,
Have seen some similar threads on these boards but still after some wisdom . . .

At clients yesterday and completed tests on a lighting circuit that was moved to the RCD side of the board.
Came to complete the RCD tests before packing up to go home and that is where it all began!

Using a Meggar MFT 1553 on auto set at 30ma

Got the following results:

x1/2: no trip

x1 (0): 69 ms
x1 (180): 113ms
x5 (0): 40ms
x5(180) 41.3ms

Retested (on Auto test) a further 4 times and had pretty much the same results except at for the x5 (180) where it then failed to trip, always reaching 1999 ms.

I need to go back and test just the RCD with the rest of the system isolated, but have never come across a fault like this before. Any/all help and advice greatly appreciated.

Thanks

Fish

Rampantchilli · Mar 12, 2013

Mem rcds frequently give sh@@ readings in my experience, you can replace them as you can get them easy enough, but I'd check the little earth wire is connected properly and you have adequate Ze readings

Clive P · Mar 12, 2013

Hi,

Having tested that particular type of RCD in the past I can confirm those readings are about right for that type of RCD. Not saying they are acceptable but they always in my experience have higher test readings than other comparable units.

Regards.

MarkieSparkie · Mar 12, 2013

1strangefish said:
Hi Guys,
Have seen some similar threads on these boards but still after some wisdom . . .

At clients yesterday and completed tests on a lighting circuit that was moved to the RCD side of the board.
Came to complete the RCD tests before packing up to go home and that is where it all began!

Using a Meggar MFT 1553 on auto set at 30ma

Got the following results:

x1/2: no trip

x1 (0): 69 ms
x1 (180): 113ms
x5 (0): 40ms
x5(180) 41.3ms

Retested (on Auto test) a further 4 times and had pretty much the same results except at for the x5 (180) where it then failed to trip, always reaching 1999 ms.

I need to go back and test just the RCD with the rest of the system isolated, but have never come across a fault like this before. Any/all help and advice greatly appreciated.

Thanks

Fish

When you come to testing RCD directly at the RCD terminals with the final circuit isolated, be aware of MEM technical support advice that the protective device should have a minimum 'load' of 1m T&E cable connected to it otherwise misleading results are possible.