Testing IR on a ring main

[333rocky333]

"L-N" is indeed, what I intended to type - so just a typo (now 'clarified') Thanks for noticing.

I say 'clarified' (rather than 'corrected') since I think that, even with L-E testing there is sometimes a potential risk (to connected 'sensitive' loads). For example, if there is an N-E input 'filter' capacitor in the load, then when one connects 500V DC between L and E, 500V will presumably transiently appear between N and E - potentially for long enough to damage or kill a sensitive load.

Kind Regards, John

Sorry I did not realise i actually posted that,
After i typed it, i thought maybe you was being more concise than me and relating to a L and E test somehow feeding through to the N, as you say via filters or something

 

[JohnW2]

Sorry I did not realise i actually posted that, After i typed it, i thought maybe you was being more concise than me and relating to a L and E test somehow feeding through to the N, as you say via filters or something

You were really right to post it since, as I admitted, "L-N" was what I had intended to type, and I don't think that I had realised that I ought to also give a warning about the possible risk/problem with L-E testing. However, thanks to your picking up on this, I think I have probably now clarified my point adequately - the potential 'risk' (to sensitive connected loads) is probably much less with L-E testing (as compared with L-N), but, in some situations, it does exist.

Kind Regards, John