someone help me out here please....

[sythai]

Looking at possible job for customer.

Basically I intend to split tails to supply an rcd supplying, submian feeding additional CU. Therefore bypassing the old wylex reirable unit which customer dosent want the expense of changing.

Customer wants to know why I can't put just put the RCD before the old wylex cu to protect whole existing installation and then feed submain from a rewirable in here?

Have told him that because rating of a 3036 is 1ka this wont be sufficient as PFC is higher than this. Is there any other additional reason which I have missed ? Basically this chap is an electrical engineer, member of IEE etc, sound chap but has been reading part P doc, regs etc and would be nice to back to him with as much detailed info as possible... maybe quoting a reg or 2?

Many thanks,

Sy

 

[Sparky Ninja]

Could you not just replace the existing unit and combine everything into one?


Sometimes doing work for people like this can become a headache, I had such a case earlier this year which could have got nasty, but luckily it snowed and I was able to be proven correct.

 

[sythai]

The customer is a decent chap a want to help him out, he is not trying to catch me out.... just interested in regs behind everthing, I know a fair bit, but still learning a lot all the time

Therefore bypassing the old wylex reirable unit which customer dosent want the expense of changing.

Did try for a full cu upgrade but not keen, trying to keep cost down.

Any one got any thoughts please?

Any other reason apart from pfc issue not to put rcd on old 3036 cu

Thanks again,

Sy

 

[Sparky Ninja]

Are you installing a second unit with new circuits?

 

[sythai]

Yep installing another cu with couple of circuits....

 

[Kiers1970]

if he's in the know, and he's worried about cost, just do what you have outlined, can't do more than that can you.

 

[Sparky Ninja]

Yep installing another cu with couple of circuits....

Apologies, but I can't see how installing an additional cu, and an rcd, and the Henley block or which ever means you use to split, is in anyway less costly then replacing the existing? Or is the existing tp&n or too large or something?

 

[JUD]

Any other reason apart from pfc issue not to put rcd on old 3036 cu

Thanks again,

Sy

Division of installation.

See 314.1

(i) avoid hazards and minimize inconvenience in the event of a fault, and
(iv) reduce the possibility of unwanted tripping of RCDs........

Page 39 BRB

 

[Des 56]

Looking at possible job for customer.



Have told him that because rating of a 3036 is 1ka this wont be sufficient as PFC is higher than this. Is there any other additional reason which I have missed ?

Many thanks,

Sy

It has been stated that the installation in domestic , the pfc is covered by the suppliers fuse
Unless there is issues with the Rcd tripping i se no reason not to Rcd the lot
Obviously testing of the existing would have to be carried out before doing so

 

[JUD]

It has been stated that the installation in domestic , the pfc is covered by the suppliers fuse
Unless there is issues with the Rcd tripping i se no reason not to Rcd the lot
Obviously testing of the existing would have to be carried out before doing so

Because an earth fault on any one circuit would knock out the power to the whole house.

If this happened at night, then you could end up with people falling down the stairs

 

[Des 56]

Because an earth fault on any one circuit would knock out the power to the whole house.

If this happened at night, then you could end up with people falling down the stairs

The granny card is being played

Sorry, I dont buy the "reduce the inconveniance pitch" that has played out for a few years now
Its better Rcd protecting whats there than leaving be

No help by me for the subject of the post, but an opinion that the customer is being realistic

 

[sythai]

Thanks chaps for your replies...

This is what I've emailed matey:

"Having the RCD to cover the whole installation, is not the best way to set it up, if you look at ‘Division of installation’ See regulation 314.1 BS7671’

It would also make me responsible for the whole installation, therefore involving a test, inspect and certification of the whole installation. Which would also add extra cost. Hope you understand, but personally I would rather not do it this way."


He seemed happy with that, also works out cheaper for him £150 to split and put in RCD for submain, as opposed to £350 for CU change.


Makes it more staright forward for me, as can see that whole place being 'a can of worms', had enough last week of RCD's banging out and fault finding!!


Thanks,


Sy

 

[Des 56]

Happy customer = Happy spark = Perfect compromise then

 

[sythai]

Yep sorted.....