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C

cmp260

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

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.
 
Last edited by a moderator:
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.
 

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