RCD testing - metrel MI3000

[gazdkw82]

Been noticing that when I run an auto RCD test I sometimes get a failure on the x1 and sometimes x1/2. However when performing the tests individually everything is fine.

Has anyone had these issues?

 

[Andy78]

Nope. Any particular times it seems to happen ?

 

[Deleted member 26818]

Been noticing that when I run an auto RCD test I sometimes get a failure on the x1 and sometimes x1/2. However when performing the tests individually everything is fine.

Has anyone had these issues?

When you do the tests individually, are you doing the 180 degree test as well?

 

[gazdkw82]

When you do the tests individually, are you doing the 180 degree test as well?

Yes. Doing both sides

 

[gazdkw82]

Nope. Any particular times it seems to happen ?

1x and 1/2x

 

[Wilko]

Hi, I don’t have your tester so I can’t say about your issue directly. But, perhaps it’s the RCD (?). My thought being that after years of no operation or testing its movement might not be working to spec initially. If I get an auto test fail (rare) I don’t immediately retest. I hit the RCD test button a few times, recheck I’ve picked the right RCD type on the test, then re run.

 

[Gareth Brookes]

Are we not doing an rcd test to prove they react quick enough incase of a fault to earth surley by pressing the test button you have woke it up and now not testing it under realistic fault conditions

 

[Andy78]

1x and 1/2x

Sorry I meant apart from factors to do with the tester. Brand of RCD, type of RCD, testing from device terminals or down circuit, etc ?

 

[gazdkw82]

Sorry I meant apart from factors to do with the tester. Brand of RCD, type of RCD, testing from device terminals or down circuit, etc ?

No nothing consistent. Recently had a job where the RCD was tripping at half times on auto test but when I performed the half times on it's own it was fine, no matter what side of the wave. The other day I had the opposite, auto test failed because at x1 the RCD was too slow to trip. Then performed it on it's own at x1 and it was fine.

Tbh both RCD's we're over 10 years old. However still seemed odd

 

[Andy78]

Was the auto test repeated after the manual tests and did they continue to give fail results ?

 

[gazdkw82]

Was the auto test repeated after the manual tests and did they continue to give fail results ?

Yes. I will try and perform a few tests tonight on my board. See if there is any difference

 

[Andy78]

also double check the settings on the auto test function. I have inadvertently altered mine before whilst being careless putting it away.

 

[Wilko]

Are we not doing an rcd test to prove they react quick enough incase of a fault to earth surley by pressing the test button you have woke it up and now not testing it under realistic fault conditions

Yes, but I don’t think it’s wrong to give it a few warm up stretches. After all, the manufacturer asks for it to be tripped 4 times a year and so if it’s 10 years old that’s 40 it’s probably not had. If it doesn’t trip with the test button then that’s that really.

 

[Gareth Brookes]

Yes, but I don’t think it’s wrong to give it a few warm up stretches. After all, the manufacturer asks for it to be tripped 4 times a year and so if it’s 10 years old that’s 40 it’s probably not had. If it doesn’t trip with the test button then that’s that really.

4 times thought it was once every 6 months

 

[Wilko]

Yes, but only had 1 six month test so far .