New sockets in workshop

[Fireblade]

Hi All

First post, so hope it's in the right place and I've followed all the rules...!!

Been asked to quote on a job which in the workshop of a car dealership. Job is to provide x2 new socket outlets. Original installation has numerous three phase DB's, not to mention all the steel conduit throughout the workshop for all the obvious reasons.

My thoughts are to avoid having to fit new steel conduit but to run 2.5mm 2 core SWA (utilising armour as CPC) from an existing switched double socket to a new switched FCU and then feed x2 double sockets as a radial from the new FCU again in 2.5mm SWA with the amour utilised as the CPC.

Any thoughts/comments

Cheers

 

[malcolmsanford]

I have nothing against a 3 core SWA and utilising that 3rd core as a CPC, if by design the SWA is not capable on it's own to provide a good enough conductor. In this scenario a 3 core of say a 1.5mm armoured would, by utilising a 3rd core as a cpc will be 1.5mm. If you utilised the SWA as the CPC then you would have the equivilent of 15mm which is in my mind vastly safer.

I can not comment on the installation you have outlined, as bad termination and installation can be achieved with any kind of containment. I have lost count the amount of times I have removed a face plate and the earths, lives or neutrals have fallen out, or indeed been out, does that make cable and a screwed termination a poor design?

I can only say that a correctly terminated SWA into a gland and then that gland terminated correctly, and I'll use the banjo as the example, then believe me that cable will not come out by accident or any other influence other than the deliberate removing of it by intention.

Would you run a 3 core MICC cable as you would not feel uncomfortable with utilising the outer sleeve as a CPC? Most electricians would say no, that is crazy, but have no problems with runing a 3 core SWA because it is safer.............absolute poppycock, it's not safer it is easier than sitting down and doing a design where you would need to think.

 

[Engineer54]

Why change the installation method??? The whole of this workshop sounds as if it's been professionally kitted out in Galv conduit, (and rightly so too) ...Along comes a DI who has never touched conduit of any type, and thinks that SWA is the way to go to extend a ring circuit!!! Any electrician worth his sort, wouldn't think twice about not continuing the present galv conduit installation..

These days, it seems if it's not T&E /capping or SWA then they are buggered, and will do anything to use a form of wiring that is easier to install, even if it's to the detriment of the existing installation. .....I guess that's what they call progress these days!!!! USE GALV CONDUIT for god's sake !!!

 

[somersetsparks]

Just to add my 2p worth.
The OP designed a perfectly acceptable installation, personally though I too would use conduit in a workshop as swa can get pulled of the wall pretty easily, especially when the cleats have gone a bit britlle, however the OP has to win this job so I imagine he has to keep costs down etc. and without looking its hard to say what I would do exactly.

As for the argument about 2 or 3 core, I would always use 2 core for single phase, where the CSA is adequate, its good solid engineering, and the cores are the right colour.
Banjos - I was always led to believe that banjos were for enclosures which had no earth termination or placcy enclosures. I always use serrated washers, scratch away the paint and do the gland up TIGHT.
I have seen loads of jobs where they have banjos all over the shop linking to the eath terminal which is joined to the same bloody enclosure but the glands are only finger tight anyway! You wouldn't go linking everything with pyro would you?
On some jobs I have been on recently, to keep unnecessary costs down, they have had conduit and trunking systems with no earths at all. Keeping costs down, think 1/3 off cable cost (probably 1/2 million saved over whole job), Huge amount off conduit and trunking cost due to less cable and a cheaper job for customer.

 

[Engineer54]

Just to add my 2p worth.
The OP designed a perfectly acceptable installation, personally though I too would use conduit in a workshop as swa can get pulled of the wall pretty easily, especially when the cleats have gone a bit britlle, however the OP has to win this job so I imagine he has to keep costs down etc. and without looking its hard to say what I would do exactly.

I don't think it has much to do with costs, ...as material wise, conduit in all likelihood would be cheaper. Labour may be more expensive, without the skills required. But if the skill is there, then conduit would be probably go in just as quick as the SWA, but even if it takes a little longer, ...it's well worth the effort!!!

 

[Hawk81]

Why change the installation method??? The whole of this workshop sounds as if it's been professionally kitted out in Galv conduit, (and rightly so too) ...Along comes a DI who has never touched conduit of any type, and thinks that SWA is the way to go to extend a ring circuit!!! Any electrician worth his sort, wouldn't think twice about not continuing the present galv conduit installation..

These days, it seems if it's not T&E /capping or SWA then they are buggered, and will do anything to use a form of wiring that is easier to install, even if it's to the detriment of the existing installation. .....I guess that's what they call progress these days!!!! USE GALV CONDUIT for god's sake !!!

I am very confused by your answer here. Firstly how do you know the op is a DI? Is there any need for you to speak to anyone the way you have in your reply? yes i agree the galv conduit would look best but that is only an opinion and there is absolutely nothing wrong with the design by the op. Saying things like "for gods sake" is no help to anyone. Recently i have saw people complain about the elitist attitude on this forum and I am starting to see it myself now. You are one of the main reasons I see it. The way you have answered alot of posts is degrading to many others and I am not the only one to notice.. The use of CAPITALS and !!!! makes it seem like you are shouting and who give you the right to come on and shout at anyone. It is not a nice way for a new member to see the forum. Maybe if you answered with more manners your suggestions might be listened too.

 

[Engineer54]

I am very confused by your answer here. Firstly how do you know the op is a DI? Is there any need for you to speak to anyone the way you have in your reply? yes i agree the galv conduit would look best but that is only an opinion and there is absolutely nothing wrong with the design by the op. Saying things like "for gods sake" is no help to anyone. Recently i have saw people complain about the elitist attitude on this forum and I am starting to see it myself now. You are one of the main reasons I see it. The way you have answered alot of posts is degrading to many others and I am not the only one to notice.. The use of CAPITALS and !!!! makes it seem like you are shouting and who give you the right to come on and shout at anyone. It is not a nice way for a new member to see the forum. Maybe if you answered with more manners your suggestions might be listened too.

There's nothing elitist about wanting to see the standard of installations in the UK remain high!!! I see far too much of those once high standards being systematically neglected and diminished...

But maybe your right, i can sometimes be too blunt in my thoughts and opinions... If so i appologise...

 

[keefy]

I think if you read my first reply again you will see I told the op his design was fine. It was only later that I said that I would use 3 core and I still stand by this. I do not understand why you are so against 3 core. Hardly any price difference and surely having a dedicated core is. Safer. I was in a workshop recently where the sockets were done in 2 core and the second socket on a 4mm. Radial had the gland broke out of the metal box and the other 5 sockets had no earth.

It seems Malcolm is intend on pushing his opinion that the more money you save, the better the job. Maybe you should let people be Malcolm and do the job as they prefer, as long as it is done well and safely surely that is the most important, not about picking hairs; having an extra core in the SWA. As I previously mentioned in this post, it is actually difficult to get 2 core these days, and when you do it is not that much cheaper as it is a special and no more difficult to install. This forum, I was under the impression, is meant for discussion debate and sharing of knowledge, if you want to show off your superior knowledge, try doing it in a polite, informative way in future.

 

[Hawk81]

There's nothing elitist about wanting to see the standard of installations in the UK remain high!!! I see far too much of those once high standards being systematically neglected and diminished...

But maybe your right, i can sometimes be too blunt in my thoughts and opinions... If so i appologise...

Fair enough. It was not your ideas that I was saying were elitist but the way you put them accross.