Earth Leakage Clamp Meter

[sparkycomuk]

Hello everyone..... :D This is my first post .....Be gentle. I am interested if anybody has any experience with an earth leakage clamp meter. The Fluke 360 clamp meter states that it can check earth leakage (if clamped around L+N) while a circuit or installaion is live, and apparently will substitute carrying out an insulation resistance test.

It sounds like a good idea, as you could confirm the IR and expected leakage (RCDTripping) before giving a Quote for a consumer unit change without turning the power off. Thus taking away the "It never used to trip" scenario

Also, would it find a faulty cable leg in a circuit if it was clamped around a twin and earth cable

Thanks in Advance .....Mark

[ianmacd]

I think you will find that the clamps will need to be on each tail individually so doubt it will work on a T&E cable.

Welcome to the forum.

[steptoe]

Im not known to that meter personally, but any milli amp leakage meter Ive ever used previously was never as simple as what you describe, and always involved at some point turning off the power,
at the very least a base is required when you are using currents as small as these, esp with a clamp meter and all the other inducted currents around.
I am doubtful, but hope it works, would save a lot of hassle.

[Apache]

Hello and welcome, anyways :D

[Evans Electric]

New one on me , Sparkycom , welcome to the Forum anyway.

Deke

[Lurch]

If you read the manual I think the 360 is supposedly a high accuracy meter, reading low currents that other ones cannot do to a reasonable tolerance. You seem to have to place the conductors in a perfect place within the jaws depending on the reading you want, which is the downfall I think.

Good idea in theory, doubtful that it will work in practice though.

[kme]

Would be in agreeance with my esteemed colleagues.

KME

[batty]

Would be in agreeance with my esteemed colleagues.

KME

He's not drunk to early for him to get steamed up.
:coat

[kme]

He's not drunk to early for him to get steamed up.
:coat

Who would you be referring to, my little bouncing friend??

[sparkycomuk]

Thanks for the replies

This is copied from the Fluke UK site

The Fluke 360 leakage tester is a rugged and accurate solution for leakage current measurement.
Ideally designed for non-invasive checks of insulation condition, the Fluke 360 leakage meter allows you to perform tests without powering down the installation or disconnecting equipment - saving you time, without compromising on quality or safety.

The unique jaw design of the Fluke 360 AC Leakage Current Clamp Meter eliminates the influence of adjacent current conductors, and minimizes the effects of external magnetic fields, even at low currents. This allows you to perform accurate and reliable tests in today’s crowded electrical environments. The tough and high-quality jaw design of the Fluke 360 leakage tester guarantees high stability for long-term repeatability and durability.

Why leakage current testing?
Leakage currents can be an indicator of the effectiveness of insulation on conductors. High levels of leakage current may be present in circuits where either the insulation resistance is low, or electronic equipment with filters is used. Leakage currents can cause disruptions of the normal operation of equipment and installations. It is possible to locate the source of leakage currents by using the Fluke 360 leakage current clamp meter and taking methodical measurements throughout the installation. The big advantage of leakage current testing versus insulation testing is that the installation and equipment do not need to be powered down but can be done during normal operation.

I think I will have to E-mail Fluke


PS: I read on IEE site that they work the same as an RCD..... "The idea is to clamp the phase(s) and neutral at the same time. This is then exactly the same reading that the RCD makes. If you try and measure the earth connection, you will be competing with all sorts of parallel paths".....So that might answer the T&E question.

[kme]

PS: I read on IEE site that they work the same as an RCD..... "The idea is to clamp the phase(s) and neutral at the same time. This is then exactly the same reading that the RCD makes. If you try and measure the earth connection, you will be competing with all sorts of parallel paths".....So that might answer the T&E question.

Can`t see that, mate. If you`ve clamped phase and neutral, there should be zero magnetic field (in a non-leaky cct), therefore meter will not read.
Your post didn`t say what the meter`s spec. was with regard to measuring ranges.

There aren`t that many (domestic) locations, where you could clamp phase and neutral without any other cable being involved. I also wouldn`t have thought that a clamp meter would work to a tight enough tolerance to find leakages.

Further. If you DO find a leakage using the meter, how do you determine its location? By their own admission, the reason for doing it that way is to leave the circuit energised. But, how do you know a leakage is an installation fault, as against a unit that, by its nature, leaks (e.g. surge supression or switch-mode power supply) ?

KME

[WarrenG]

I have the Megger DCM300E nd does pretty much the same in terms of lamping live conductors.

http://www.transcat.com/PDF/dcm300e.pdf