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pete555

recently had a test with 2 cables being used for sub main

1st is a 10mm swa 2 core with armourings for earth

2nd is a 6mm swa 3 core with armour and integral earth

both cables doubled up on MCCB 63 a breaker
and both terminated in DB

what code

i think 2

ive told them its grim and needs 1 cable to go but not sure if i should have coded it a 1
 
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Where are those rules as they are not in BS7671 as far as I'm aware? I agree its good practise to make sure all things are equal, but in this case they are not and the BGB basically says thats Ok with special consideration! Hence the guy doing the EICR needs to be sure of his facts if he is going to recommend additional work.

Is that not 523.7 -(i)

OK, but (ii) seems to give a get out. As I've stated before if I was doing something similar I wouldn't contemplate different sized cables.
 
OK, but (ii) seems to give a get out. As I've stated before if I was doing something similar I wouldn't contemplate different sized cables.

There is no get out!! Parallel circuits are standard everyday practice, end of!!

The parallel installation in the OP's case is wrong, it contravenes parallel circuit criteria in at least 2 instances that we know about. So you were right to pick this up and code it...
 
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You obviously totally rely on BS7671 for all the answers, and if it's not in there, then something has just got to be wrong!! lol!! Well i have some devastating news for you, BS 7671 (and it's OSG's) is/are only a guide it is not and never has been the definitive bible you seem to think it is. Broadly speaking it's scope is also somewhat limited and would be almost impossible to cover everything.

I work to BS7671 because thats relevant to what I do and to what most people do on the forum and for the Op this is probably the most relevant document for his situation, he can correct me if I'm wrong. On your project you may work to other documents thats fair enough but are they relevant to what I (and maybe the OP) do - unlikely?


It also assumes, that the reader has a broad understanding of electrical technology.

Are you trying to imply I don't?

Wrong the guy undertaking an ECIR needs to be experienced, knowledgeable and competent enough to be able to conduct and assess the installation he is inspecting/testing and be capable of advising on any remedial work that may be necessary, without having to always confer with a guide book of Reg's!!

There are very few people who don't have to refer to the regs at sometime. The whole point of an EICR is to make observations and back that up with a reason which is usually associated with a reg no. No-one would be able to quote every reg number and sometimes you see something it maybe doesn't look right but when you delve deeper you find it maybe ok or the actual reason why it doesn't look right. In the case of the OP, he's seen something that doesn't look right, I'm just pointing to something that MAY show it is OK. What he choses to do with that information is up to him, he's the one signing the EICR.

What has my last paragraph got to do with this thread?? Well if you think about it for a second or two, ...what single cable size would be capable of supplying 3200A?? NONE, this is/was a perfect example to show you that parallel cabling is the only way that it would be possible to interconnect between the source and the main switchboard... Yes there are other methods, but we are talking about cabling solutions...

But the thread has got nothing to do with this. I've already agreed that I wouldn't use different cables so what are you trying to prove? We all know you are knowledgable but sometimes your arrogance and intolerance of others just winds me up!
 
I work to BS7671 because thats relevant to what I do and to what most people do on the forum and for the Op this is probably the most relevant document for his situation, he can correct me if I'm wrong. On your project you may work to other documents thats fair enough but are they relevant to what I (and maybe the OP) do - unlikely?

I work to various Country codes and regulations, including BS7671. Most overseas project specifications will denote ''designed and installed to the highest international standard''. And yes they are relevant as All those standards will say exactly the same thing as far as parallel circuitry is concerned!!

Are you trying to imply I don't?

I was pointing out that that your statement was misinformed... I have no idea if you, or come to that anyone else here have a broad understanding of electrical technology, i was merely making a statement...


There are very few people who don't have to refer to the regs at sometime. The whole point of an EICR is to make observations and back that up with a reason which is usually associated with a reg no. No-one would be able to quote every reg number and sometimes you see something it maybe doesn't look right but when you delve deeper you find it maybe ok or the actual reason why it doesn't look right. In the case of the OP, he's seen something that doesn't look right, I'm just pointing to something that MAY show it is OK. What he choses to do with that information is up to him, he's the one signing the EICR.

I'm not saying you shouldn't use the Reg's as a guide, just don't be surprised that what your looking for isn't covered, or doesn't give you a definitive answer. So finding a relative Reg number to substantiate a defect observation isn't always possible.


But the thread has got nothing to do with this. I've already agreed that I wouldn't use different cables so what are you trying to prove? We all know you are knowledgable but sometimes your arrogance and intolerance of others just winds me up!

Sorry i got a little confused as to who the OP was at this time. lol!! It was included to give an example of why parallel circuits are a standard everyday practice.

Sorry you feel that way, but i'm afraid you have to take me as you find me!! I certainly don't see myself in that light, and don't think that way either, but i suppose we all have our off day's.
I do know that my tolerance/patience levels are unfortunately not what they used to be!! ...lol!!!
 

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