MK 63amp RCD that fails Ix5 test everything else tests fine on the board

[stuarth]

I have a brand new MK 63amp RCD that fails Ix5 test everything else tests fine on the board, I tested with all circuits off everything unplugged so swapped it for another thinking must have a faulty one but the same result, it will trip at 50ms and ramp tested at 33ma, ze=0.18 what could be happening? any advice on what could be wrong would be greatly appreciated.

 

[Midwest]

Has all the other initial testing been ok?

 

[HappyHippyDad]

I'm sure I'm missing something here and will be promptly corrected, but.... the RCD doesn't trip within required times so change it for a new one that does.

 

[Bob Geldoff1234]

I'm sure I'm missing something here and will be promptly corrected, but.... the RCD doesn't trip within required times so change it for a new one that does.

See post 1.Do keep up

 

[HappyHippyDad]

See post 1.Do keep up

Oh dear
I thought it seemed too obvious!

 

[davesparks]

I'm sure I'm missing something here and will be promptly corrected, but.... the RCD doesn't trip within required times so change it for a new one that does.

You are correct as far as I know, the tripping time is set by the manufacturer and a property of the individual unit.

 

[davesparks]

it will trip at 50ms and ramp tested at 33ma, ze=0.18 what could be happening?

That's not right, if it trips at 33mA then its faulty, it should trip between 15 and 30

 

[stuarth]

Has all the other initial testing been ok?

Yes all tested good, nothing to suggest there would be any issue had high resistance on the cps on both ring circuits but after investigation a couple of sockets had there sleeving clamped in and a couple were lose but retested good.

 

[stuarth]

That's not right, if it trips at 33mA then its faulty, it should trip between 15 and 30

Its the second RCD they can not be both faulty surely?

 

[freddo]

We had about 8 MK 6a RCBOs recently with a similar fault. Tripped fine at 1x, at 5x or more they would not trip at all. Tried 3 different test meters.

 

[Midwest]

We had about 8 MK 6a RCBOs recently with a similar fault. Tripped fine at 1x, at 5x or more they would not trip at all. Tried 3 different test meters.

Not one of those faulty batch?

 

[kenny maccuish]

Have you tried a different make in place of the MK one? Just as a temporary test to see what results you get with that. Or maybe get another MK one from a different supplier if its possibly a faulty batch.

 

[Octopus]

I think the OP should re-do his IR tests ..............