100ms time delay rcd on main domestic unit?g

[cmp260]

my house has 100ms time delay rcd main switch. why would this have been installed in a house? is it legal?
thanks

 

[brman]

ok thanks brman, ill rip up the stopcock cover tomorrow

Sounds a good plan.
And, now I think I understand it a bit better I think you could do worse than get a quote from the guy that did the EICR to sort out the high Zs and disconnect the unused ccts. If he was cheap on the EICR he might end up being cheap for the remedial and I am starting to think he might actually have done a good job on the EICR............

 

[cmp260]

steve, youre right its rightly failed on some aspects, but wtf does high impedance on 25 on circuits 2 and 3 mean?

 

[cmp260]

and he did fail it for having a 100 ms td main, why?

 

[Octopus]

steve, youre right its rightly failed on some aspects, but wtf does high impedance on 25 on circuits 2 and 3 mean?

FOR GODS SAKE MAN get the EICR out and list the readings you've been given on here - or hasn't he given you a full report??

 

[cmp260]

ok dude, chill out, its a lot of typing and i cant attach it, hang on ill make a dropbox link

 

[trev]

steve, youre right its rightly failed on some aspects, but wtf does high impedance on 25 on circuits 2 and 3 mean?

I have no idea what that means but why don't you ring the guy tomorrow and ask him. It could be that he had a slight brain fart.

A word to the wide though, don't tell him you've been asking questions on here. He would probably be offended, I know I would

 

[Octopus]

ok dude, chill out, its a lot of typing and i cant attach it, hang on ill make a dropbox link

Try Cooker circuit 40A MCB type then the earth fault loop reading

eg. 40A BS60898 0.89

 

[cmp260]

heres the doc. i did ring him on fri and asked him, he said hed get back, but hasnt..

hers thendoc http://db.tt/a09WQgKS
cheers

 

[cmp260]

trev, thanks for the advice, and i know wha t you mean, but how would you suggest i tell him that a 100ms td is not a fail?

 

[trev]

trev, thanks for the advice, and i know wha t you mean, but how would you suggest i tell him that a 100ms td is not a fail?

Simple, you don't. You could ask him why it's a fail though. Seriously, just ring him and ask him to talk you through the report, I'm surprised he didn't do that anyway. It's something I do as a matter of course because my clients, like you, are not electricians. If they were they wouldn't need me.
Call him up, get him to talk you through everything and tell him to explain it in layman's terms. jobs a goodun mate(hopefully)

 

[guest119]

steve, youre right its rightly failed on some aspects, but wtf does high impedance on 25 on circuits 2 and 3 mean?

Ring main end to end readings?


Boydy

 

[Gentle Ben]

As has been said by others the '25' is probably zs, the total resistance of the earth loop going all the way to the suppliers transformer.

On the table of test results for the circuits that have failed their should be an R1 + R2 result, what are these? This should confirm whether the high impedance is in your installation or on the suppliers side.

Too high a zs can be caused by poor or loose connections. I would always advocate finding the cause and repairing it but you can get round it by down-rating the MCB which allows a circuit to have a higher zs or converting to RCD.

 

[richy3333]

Please stop poking things in sockets mate.

No Trev, he should. Natural selection will then do it's bit for mankind...

 

[Octopus]

heres the doc. i did ring him on fri and asked him, he said hed get back, but hasnt..

hers thendoc http://db.tt/a09WQgKS
cheers

One or two slip ups on there me thinks. How long did it take him to do?

 

[richy3333]

Just a guess, but it looks like the fail comment in respect of the 100mA RCD is because it's protecting circuits? Kitchen RFC in particular?

 

[brman]

reading those results I can see why he failed it. Zs of 50ohm on cct 3 is over 10 times what I would expect for a start so you have a fire waiting to happen there........

As Murdoch said, there are a couple of anomalies on the sheet but it is basically believable so you do need some work done to make it safe.

I still can't see why there is a C2 on the main RCD but, as others have said, why not ask the guy?

 

[brman]

Just a guess, but it looks like the fail comment in respect of the 100mA RCD is because it's protecting circuits? Kitchen RFC in particular?

maybe, but I'd give that a C3 unless of course there is a socket that could be expected to be used for outside equipment. (ie. outside socket spurred off the kitchen ring)

 

[Heisenberg]

Any chance you could also upload the other pages he gave you to Dropbox?

 

[cmp260]

One or two slip ups on there me thinks. How long did it take him to do?

it took him about about 2 1/2 hours for 4 bed house,
when I asked about the 100ms delay, he said thats unsafe since thats long enough for a fatal shock, there should be no delay and thats why it failed. is he right to fail it or is this a grey area?
should he be using a special meter to text the td?

 

[cmp260]

its typed on the form, definitely 25

 

[cmp260]

maybe, but I'd give that a C3 unless of course there is a socket that could be expected to be used for outside equipment. (ie. outside socket spurred off the kitchen ring)

actually, that could be it, there is an outside socket running off the kitchen ring however its one of those aldi kits with a builtin rcd plug that you simply plug into a spare socket in the kitchen.
if thats the case, can you explain how the td would make a difference?
thanks

 

[richy3333]

If a socket is in a position that makes it accessible to being used outside then he would code it accorcdingly. I guess this is the reason, rather than the Aldi DIY job?

 

[Jonny66]

Incredible, 5 pages of guess work, assumptions and opinions based on what? technical information from a DIY bt man with no knowledge of electrical installations? who is a little aggrieved to have been given an unsatisfactory EICR? and cant interpret the certificate? but who owns a multimeter? .........

Come on, he went for the cheapest quote from "MY ----er dot Con":smilielol5:...... where all the monkeys try to out quote each other until only the most desperate, deranged and possibly feeble minded amoeba like DIs are left......and get this, unbelievable I know, he still picks the cheapest.... incredible......and to top it off, like a little cherry on top, he now wants the cheap EICR scrutinised for free by electricians who have not seen the install and who would of most likely charged a decent rate in the first place.......well, what can you say but IMO tough, pay someone a proper rate and get it done again if your not happy.:6:

And just out of interest, why dont we all post up one of our own EICRs (with no other information or further posts to justify what codes you gave) and sit back as they are torn into by others from a distance with guess work and assumptions based on nothing.....silly I know, but I bet no-one would want to.....any takers??

 

[cmp260]

Incredible, 5 pages of guess work, assumptions and opinions based on what? technical information from a DIY bt man with no knowledge of electrical installations? who is a little aggrieved to have been given an unsatisfactory EICR? and cant interpret the certificate? but who owns a multimeter? .........

Come on, he went for the cheapest quote from "MY ----er dot Con":smilielol5:...... where all the monkeys try to out quote each other until only the most desperate, deranged and possibly feeble minded amoeba like DIs are left......and get this, unbelievable I know, he still picks the cheapest.... incredible......and to top it off, like a little cherry on top, he now wants the cheap EICR scrutinised for free by electricians who have not seen the install and who would of most likely charged a decent rate in the first place.......well, what can you say but IMO tough, pay someone a proper rate and get it done again if your not happy.:6:

And just out of interest, why dont we all post up one of our own EICRs (with no other information or further posts to justify what codes you gave) and sit back as they are torn into by others from a distance with guess work and assumptions based on nothing.....silly I know, but I bet no-one would want to.....any takers??

well it is an advice forum, i was looking for advice and I mostly got it, very helpful comments and i really appreciate this. I suppose reading comments from the likes of you with chip on shoulder is fair price to pay for free advice. chill out dude, youll give youself an ulcer..
by the way im not BT, I had one year training in military in electronics and full spectrum of telcomms from landline to microwave to pbx followed by multiple courses in various PBX systems in civvie land and working for major interconnect.

 

[telectrix]

one problem with threads like this is that it's not possible to convey all the info across the internet. otherwise a post could take up 2 pages. then readers of the post have to fill in the blanks and read between the lines. this results in the post being mis-interpreted to a greater or lesser degree and then out come the negative replies. it's a bit like a surgeon trying to remove a tumour when he doesn't know where it is.