Earth Leakage Trip Problem Ask questions and find answers to many subjects relating to electrics and electrical work

[elliotts@cockerham.fslife]

About 20% of the time we switch on garage lights the trip comes out even though neither the live for those lights nor its negative go through the side of the consumer unit the trip protects. Since this is a new build, it foxes me (and sparks). Any ideas?

[sparx]

Are the lights fluorescents, if so check connections in fitting terminals for loose wires, crossed neutral/earths etc.
Even though not on rcd 1/2 of board can still cause rcd trips (well documented problem).
If no faults found try changing fluor. for lamp holder temp. see if fault clears may be duff fitting,
hours of 'fun' to be had on this kind of fault.....
regards SPARX

[elliotts@cockerham.fslife]

Thanks Sparks. Will try alternative to fluorescent light. What about less sensitive fitting (is 100 mA the next one up?). Intrigued about this being a well documented problem. How can I hear more about it?...Brian

[sparx]

Hi agn Brian, yes 100mA is next one up but does not give sufficient protection to sockets. Well documented...in trade press and manufacturers info. only sent to members of trade associations etc....ECA or NAPIT did recent article in magazine not sure which but am trying to find it, believe it related to TN-C-S (pme) type of supply with Neutral - earth fault.
Suggest your sparkie rings tech. help line of whichever trade organisation he belongs to they are very helpful & keep a good database of reoccuring probs., regards SPARX