CalCard, dedicated socket and RCD

[ringer]

Have just got myself a CalCard to keep a running check on my newly calibrated MFT. No problem with continuity and IR tests using the card, but am now looking at how, exactly, to set up other tests, being Zs and RCD tripping. Instructions suggest either a dedicated socket on a dedicated RCBO, or a dedicated non-RCD protected socket and use of a plug-in RCD adaptor.

I am thinking option 1 (RCBO) will trip the protective device when I try to measure Zs, so do not see how this will work, unless I test on no-trip which is notoriously inaccurate and unreliable. RCD test should be no problem.

Option 2 (RCD adaptor) will enable me to do proper Zs (without the adaptor) and RCD (with the adaptor plugged in), but will a RCD adaptor be suitable to test RCD tripping? Am thinking these adaptors are cheap and perhaps not really representative of how a proper RCD will perform.

Can anyone with a working set-up like the above confirm how well either option will work?

 

[telectrix]

i use a particulr socket ( RCD protected) to check no=trip Zs. then do a Ze test to check the accuracy at high . hope this helps.

 

[ringer]

Do you get repeatable readings on no-trip?
I thought the point of testing Zs is that you don't have to isolate the installation, which you have to to do Ze?

 

[telectrix]

true. but it's only to check the MFT accuracy. should get same readings every time.

 

[Sintra]

I have a single non RCD protected circuit mounted below the DB in the office with a single RCBO protected socket next to it. Able then to do all checks.

 

[ringer]

Sounds like a good way to do it, Sintra. My board is a 16th Ed type with the two spare ways both being on the RCD side so will have to do a bit of rejigging in there.

 

[MarkieSparkie]

You aware using a Calcard does not verify that your test equipment is functioning within the limits set out in GN3. The test instrument voltage and current output must also be verified. Megger and Transmille checkboxes do this. If your'e unfortunate enough to have to testify in court you will be expected to be able to provide evidence that your kit was/is within the limits set out in GN3.

 

[ringer]

I have been looking through GN3, without success, to find the appropriate paragraphs where it is stated that the instrument voltage and current output must be verified. Please quote the appropriate page numbers/paragraphs in GN3 where it is stated that these parameters must be verified, and the appropriate time interval in which that verification should take place.