rcd testing

[tc50]

hello im new here and baffled after today.doing rcd trip times test with newish newlec multifunction tester.new install 0n up and down ring circuits on separate rcds trip x half ok on both trip x 5 ok on both less than 40 m/secs but trip x 1 on both rcds tripped rcds but no readings due to safety cut out on meter indicating 50 v ,have lost manual so not sure what this means but strange on both new circuits and new hlgh integrity board rcds would appreciate any views.

 

[telectrix]

if you are testing at the RCD using probes. it could be a momentary bad connection when the RCD trips. try at a socket using the 3 pin plug.

 

[tc50]

if it was i cant find it aka not good on computers but thanks i,ll look for it.

 

[tc50]

its plug in type to sockets on both manual and auto though it might be meter fault but tried it at home all ok could it be an applience plugged in that ive missed unplugging or existing circuits now rcd controlled but had meggered and tested ok

 

[tc50]

thanks by this i presume you mean disconnect all circuits except rings and retest then each circuit individually to trace problem .....bummer looks like i,m working tomorrow then ....for free boo hoo

 

[Richard Burns]

You would only need to test the RCD on its own with no other circuits connected. Switch off all MCBs and test the RCD at the load side, two minutes, done (if it works); make sure you are not generating an earth voltage fault from static.

 

[DaveyD]

if its a Megger throw it in the bin and get a Fluke

Someones started a fire ...

 

[tc50]

worse ...its a newlec thanks anyway

 

[tc50]

thanks man whats earth volt fault from static ?

 

[telectrix]

a degree in electronics and you can't spell your own screen name!!!!!

 

[Richard Burns]

Do not know about The newlec meter but on a Metrel the test button is used as an earth comparison (i.e using you) if you are statically charged then this charge generates a voltage on the meter when you press the test button and the meter sees this as a voltage to earth and causes the meter not to test. If you press the test button through an insulator e.g VDE screwdriver the test works.

 

[tc50]

well you learn something everyday man will try this next time it happens thanks for reply,also would you recommend metrel instruments as i,m looking for a complete new kit of everything at best rates.

 

[Richard Burns]

I have a metrel MI23002 from instrotech and I find it is great. It has rechargeable batteries, a download facility for your data (which is a bit odd but useful) doea ll the tests for PIRs and inital verification and also does phase rotation and RCD ramp test.
It does not do earth leakage current, but I have a multimeter for that, if I ever do it.
Everyone has their own favorites and most love Megger but they are more expensive and this one does all I need. the only problem is the static bit.

 

[sparkinlee]

hello im new here and baffled after today.doing rcd trip times test with newish newlec multifunction tester.new install 0n up and down ring circuits on separate rcds trip x half ok on both trip x 5 ok on both less than 40 m/secs but trip x 1 on both rcds tripped rcds but no readings due to safety cut out on meter indicating 50 v ,have lost manual so not sure what this means but strange on both new circuits and new hlgh integrity board rcds would appreciate any views.

I'm a bit confused by this thread as it looks like it got mixed up with some trolling which has now been deleted, so I'm not sure if the original problem got sorted.

So, a couple of questions to the OP to see if progress is being made...
- can you clarify what the original results were? The quote above seems to say you were getting tripping on half x but not on 1x, which would indicate some sort of problem!
- I've not seen the tester you are using, but if it has a selector to choose the rating of the RCD under test, have you checked that it is set correctly (I guess you are testing a 30mA RCD)
- exactly how were you testing? At a socket / with other items plugged in / on the bars in the CU?

 

[ackbarthestar]

I would suggest that you disconnect the the outgoing tails from the RCCBs and test with probes.
See whether of not that works and report back.... Ok?