Discuss what causes earth leakage? in the Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

ExArmy

-
Reaction score
143
testing a house today before I put RCD protection on it and i got 300mA earth leakage. appox 100mA from the sockets, 180mA on the downstairs lighting circuit, then 20 odd mA accross the rest of the circuits.

I had a poke around the downstairs lighting circuit, couldn't see anything obvious, did R2 tests at all points (OK), did IR test and it was in the region of 650MΩ L-N, L-E and N-E.

as for the sockets, 2 chest freezers that are older then me are the cause of 50mA between them, rest is unnacounted for?

what causes this?
 
There are a number of devices that may cause leakage. For example anything that involves a power supply, transformer, heating element. First step should be IR test on the circuit (all devices disconnected and protect any vulnerable equipment) to elimate any faults with the wiring (often the cause of relatively high leakage, like you appear to have).
 
I should add that some of this can be considered (arguably) valid leakage, although it's undesireable. A typical personal computer for instance would leak less than 5mA in healthy condition.
 
how have you measured this 300mA leakage? that's a hell of a leak, worse than my local plumber!!!
 
Suspect something is a bit wrong somewhere. A few mA here and there is ok with some devices but 300mA ???

Filters are devices in electronic systems often made from resistors, inductors and capacitors that control the form of input waves and as a result will of leak very small currents to earth but this is usually < a few mA.

A resistance of approx 766Ω between a Line and earth would give you 300mA of current in the cpc. I would be looking at dodgy appliances and low IR readings :)
 
pity we can't harness the power. would beat sunshine panels hands down.
 
suppy is TN-S, and it was measured using an earth leakage clamp meter.
since looking at the lights i've been told theres more lights and sockets that have been spurred off the downstairs lighting circuit in another part of the house, so when i go back i'm fairly confident I'll find the problem.
 
think it's electron confusion as the E and N are connected together at the head, the poor little buggers don't know which route to take.
 
they were fine when they were using a map and compass, but now they've been supplied with a sat.nav. that's what's buggered the poor little sods. they want to take the neutral path, but the sat.nav. directs them down the earth path, even though it's clearly marked as " no through road for electrons".
 

Reply to what causes earth leakage? in the Electrical Forum area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock