(25-06-2014, 05:18 PM)Radio Fixer Wrote: " The Neutral should be bonded to Earth at the Meter and be tagged as PME. "
Well now another two things I don't understand. What does PME stand for? And the neutral being bonded to earth. To me that is a No! No!. The neutral has volts on it and I have always understood that it should not be connected to earth at the domestic premises. I was told it is connected to earth back at sub station or the transformer that splits out the phases.
Well I hope it was the mower and yes you don't actually need an earth to it. The RCD trips because on an unbalance in the L and N wires. I will have to try it again sometime. But it still seems unlikely the lead is in good order and when I cut the stalks off the grass it was bone dry. We hadn't had rain for about a month. Gladly we had some last night.
Gary
PME means as in post #10 as far as I know.
There are various earthing systems, I'm not an expert but here our house wiring earth from the consumer unit is connected to the DNO's neutral at the meter box using a 10 mm earth cable, legally only the DNO can connect that. From there the neutral and the live goes to the top of a utility pole in the garden, I was told there was also another connection from the neutral at that point down to a buried ground mat or spike.
Once the DNO's neutral and PME reach the consumer unit they go there separate ways and must not be connected together under any circumstances even though they are connected together at the meter box.
Lawrence. EDIT: I've referred to this in the past, the system at our place is TN-C-S :
electrical.theiet.org/wiring-matters/16/earthing-questions.cfm?type=pdf (copy and paste into your address bar)
