RCD x 5 touch voltage too high

[Just]

Hi, When I test socket ring x 1 I get 44ms and when I x 5 I get greater than 25V touch.. Zs is 0.53 and Ze is 0.17, IR is low 25M. Any ideas greatly appreciated

 

[pushrod]

Think there was a thread on this just the other day, but tbh can't remember what was said,but if you are lucky someone might be able to link you to it. What tester is it - does it say anything about "greater than 25V" in the manual?
Have you tried putting another rcd in to see if you get the same result?

 

[Just]

Hi thanks, I checked the manual and it just says touch voltage too high and that old chestnut 'requires further investigation' which to be fair it does! The meter which is a Socket&See was calibrated a few weeks ago. Any other circumstances would start testing but as the x 1 was 44ms surely there must be a fault with the rcd? As you say test with another. A poor IR wouldn't have anything to do with it would it?

 

[pushrod]

Hi thanks, I checked the manual and it just says touch voltage too high and that old chestnut 'requires further investigation' which to be fair it does! The meter which is a Socket&See was calibrated a few weeks ago. Any other circumstances would start testing but as the x 1 was 44ms surely there must be a fault with the rcd? As you say test with another. A poor IR wouldn't have anything to do with it would it?

Can't see how a reading of 25MΩ could have anything to do with it tbh. Is it an rcd protecting several mcbs? Have you tried it with the other circuits turned off if it is?

 

[Farmelectrics]

the 44ms for x1 is ok as long as it trips in under 200ms

 

[Just]

Thanks farm, it's not the 44ms I'm worried about! The x1 is a fair reading which is why I am not sure x5 is greater than 25V touch. It's a TN system so it's under 400ms.

 

[Farmelectrics]

please explain do a lot of testing myself dont understand what you mean with 25v touch when i do my rcd test with my meter x1/2 x1 x5 and my meter just spits out the readings

 

[marcusone]

Test the Rcd with all loads off. Or switch off all mcbs and test the Rcd in isolation.
Many testers will give a greater than 25v touch voltage reading if the RCD doesn't trip within the required times.

Hope this helps.

 

[Farmelectrics]

does this apply to rcbos as well

 

[marcusone]

I've never had this issue with rcbos but if I did, again I would ensure loads on the circuit were off and then test.

Cheers..

 

[baazab]

rcd testwhat does 1/2 and 1/5 mean when doing testing on rcd please tellme what is thediffrient

 

[Sintra]

Basically a RCD has to be tested 6 times.

Tests 1 & 2 are at 1/2 x the RCD rated current and are performed at 0 and 180 degrees of the cycle.

Tests 3 & 4 are at 1 x the RCD rated current and again performed at 0 & 180 degrees.

Tests 5 & 6 are at 5 x the RCD rated current at 0 and 180 degrees.

 

[Farmelectrics]

marcusone when you say all loads off do you mean nothing pluged into sockets or am i missing the point when i test my rcds ie ring main sockets there is nothing plugged into them hence i then carry out my secuence of rcd test with my tester cant understand were this 25v touch voltage is from is the tster detecting this interesd to find out as i have never came across this before

 

[Sintra]

Don't understand why your meter is indicating a touch voltage >25V as this would be acceptable.

Touch voltage has to be <50V

 

[baazab]

what about ramp test on rcd what is it allabut can you explain please