Consumer unit reasoning

[TJ Anderson]

Regarding earth leakage tester,

I don't know how to use one , because I don't own one.

Simply because I have never needed one.

Any time I have been called back for a nuisance tripping fault 9 times out of 10 its been :

Dodgy item plugged in like irons , washing machines, extension leads to sheds/garages, any outside socket /light/ pond pump basically anything where moisture is likely.

Fittings being changed for fancy ones or moved for decorating and not done properly, (contemporary metal fittings that don't fit into normal back box depth,which squashes the wires which fall out, screws through wires etc..)
New Lights where there is not enough room to fit loop in/out/sw and again squashed in so they fall out.

If I disconnect circuit on a suspect RCD and the ramp test is less than 15mA I have just changed it.

This was the first time I had something that would have stumped me , as totally random and hardly any load, hence I started looking at buying an earth leakage tester and would have learnt how do use it , just like when I first learnt how to use an MFT,

I would not have give up until I had sussed problem out, and would have come on here to ask advise from people more knowledgeable than me, which is why these forums are so good.

If you think the attitude to admit I don't know something,
Am willing to buy new equipment and try and learn it,
And ask any one with better knowledge to better myself,
"leaves a lot to be desired...."
Well what can I say to that mentality?

Just get one mate, they are a great tool to have in your arsenal. Very easy to use and pinpoint faults quickly, too quickly sometimes (£) if you know what I mean

 

[Deleted member 9648]

Good pointers fella's on the advantages of an earth leakage clamp meter. Will ponder that one. Have to say though I've only ever been stumped twice by an RCD tripping issue.Both instances were only solved after several visits and a lot of head scratching,maybe an earth leakage meter would have helped. It's rare that the cause of an RCD trip takes me longer than minutes to trace,although rectifying it can take much longer!

 

[GB.Kayak]

Not expressing an opinion for once, but for those who haven't found it yet, the new OSG has guidance on p84 for those making additions and alterations to installations with non-Amd 3 compliant CUs after the new regs come into force. It specifically states that installers should NOT advise replacement purely because the units do not comply. It also discusses some of the poor workmanship issues discussed on here. Nothing about the other design issues with the units themselves though.

Once again apologies if this has already been said.

It's the first that I have read on the subject and good to see that the 'you have to change it because it's not compliant' brigade have a 'shot across their bows'; that said, I suspect that if any read it they will ignore it. It is after all only a code of practice.

 

[Midwest]

And how many of those 35 years were there RCD's present at virtually every job you went too??
Ramp testing is the poor man's alternative to a leakage clamp meter, some only ramp up in 3 or 5mA steps on the 30mA range. You could well be right about most or many leakage faults being down to low IR to earth, but it's those faults that aren't down low IR, and/or, being able to easily trace the source/cause of the fault, (including accumalative leakage problems) especially on the larger twin RCD CU's that make them a must have bit of test kit for today's electrician...

I bet i could trace an actual EL fault on a large 17th ed CU of any type, faster with just my EL tester, than you could with your MFT!!!

So Yep, it's time to purchase an earth leakage clamp meter, ...or maybe it's time to retire!! lol!!

Funnily enough I was inspired (on anther thread) to purchase said EL clamp meter, might have been you E54. I have had a couple of jobs over the past few years of nuisance tripping. I have always found (thus far), that it has been an appliance causing the problem. I think having one of these devices will speed up the process of locating offending item, as opposed just unplugging everything and see what happens. Got mine from forum sponsor for under a ton.