Expert: Master Bob - 10/22/2004

Question
First of all, what is earth leakage?

We were told by an electrician that the reason our earth leakage monitor kept tripping was that we had earth leakage into the walls when they got damp. What does that mean?

Is there any way to fix this problem?


Answer
Hi Simon,

Based on your description....it appears this question may be coming from the UK or a European country....as earth leakage and the monitors are not commonly used terms and equipment here in the US. What we refer to as "ground" - they refer to as "earth"....technically one and the same thing.

  I do have some limited information on earth leakage monitors in some of my power guide references and know that they are designed and listed to prevent fires, safeguard lives and save on maintenance by monitoring electrical cable insulation and detecting AC or DC earth loop faults - before disaster strikes. Our nearest similiar device here in the US that performs almost the same function is a ground fault circuit interrupter...or what we call a GFCI....and they too will trip when excess moisture is on live wiring - preventing a potentially dangerous shock and/or equipment damage. For this reason, they are Code required in the US for protection on any circuit location that is subject to moisture - such as bathrooms, outdoor receptacle outlets, garages, etc.

 Our GFCI's monitor the difference between the hot line and the return neutral and ground lines....and any significant difference indicates a ground fault either by contact with water or any other event that can cause a short...and this will cause the GFCI to trip.

 Based on the information I have, earth leakage monitors operate in the same or similiar fashion...

 So...with out having access to the test data your electrician has - I can't tell you exactly what it means - but I would assume that he/she is indicating that your earth leakage monitor is detecting excess moisture on the wiring and/or devices in your home....and tripping to protect personnel and equipment.

 How do you fix this problem..? Unknown without seeing exactly what is causing it - but it appears to be related to a water entry problem in your walls so you would need to seal out or otherwise prevent this water entry or build-up.

 Where the equipment you mention is not used here in the US...that's all the information I have on it. I would highly recommend you contact this electrician who advised you of the problem for more detailed information on the cause and how best to affect repair.

 Hope this helps...

Best Wishes,

Bob Osgood
Master Electrician

RKO ELECTRIC, USA

www.rkoelectric.com