Earth leakage clamp meter

TPES · May 31, 2010

I've been looking at getting a clamp meter for a while but I'd like one that does earth leakage also, there isn't many about and the ones I have found are stupid money for the rare time they will get used, megger ones are about £350, I can't justify spending anywhere near this...

Anyone recommend a good earth leakage clamp meter? That won't break the bank

IanB · May 31, 2010

As I try and specialise in RCD faults a good meter has proven invaluable. I have a KEW SNAP 2432 which has graduations of 0 to 4ma, 40ma, and 100A. I use 0 to 40ma most. It also has a peak hold function. It doesn't have any form of logging facility but that is not really available anywhere as I have asked although this was a wee while ago. Unfortunately it was in your 'expensive' price bracket.
I looked into cheaper versions but none were very cheap and a normal current meter was simply not accurate enough at these low leakage currents.
I guess you need to revit what sort of jobs you might use it for. In my experience most electricians will shy away from these type of RCD faullts as they are time consuming to fix and the customers often won't pay.
Good luck

pennywise · May 31, 2010

The NIC shop has a slightly cheaper one.

NICEIC - approving excellence

sythai · May 31, 2010

Just curious how you would use it..... where would you normally clamp it on a circuit ?

TPES · May 31, 2010

sythai said:
Just curious how you would use it..... where would you normally clamp it on a circuit ?

Heres an example of its use..
[ame="http://www.youtube.com/watch?v=5hL13UjRSoY"]YouTube - Testing a Theory: Earth Leakage (Excerpt)[/ame]

sythai · May 31, 2010

I see.... it's just for testing appliances then, or can you test fixed wiring?

Thank you,

Sy

IanB · Jun 7, 2010

Yep, you can as long as you can access the CPC on its own. I do this a lot when tracking the earth leakage split across circuits. Also works on the whole house earth. When I tested my house it ticks over at 27ma!! although only half of this is on the RCD protected circuits.

jstephens251 · Jun 7, 2010

Test Instruments Solutions do an earth leakage clamp for less than £100. Available at cef

eskimo39 · Jun 7, 2010

I am more interested in fault finding than the actual installation work. However surely you would need a meter that logs the current as most fault currents are not always present when testing.

I had a problem with a customers installation a while ago where the RCD kept tripping during the night, I checked all the circuits for earth leakage but there wasn't anything obvious. I eventually found the fault but only after numerous visits, each time disconnecting a circuit at a time until it eventually didn't trip. If I had a meter that logged the current on a circuit I could buy several of them and leave them attached to different circuits.

IanB, if for example a customer calls with an RCD that keeps tripping how would you go about investigating?? I am new to this so would be grateful for any advice (so long as it is not a trade secret)

How does everyone else investigate???