4mm Radial

[Cirrus]

I have been asked to run a new circuit into a shop for a new lottery machine. Chap wants 3 x double metal clad sockets. I was thinking of running a 4mm t&e radial supply over 15 meters. What size MCB would I be advised to put into the CU?

 

[wayne]

b20 does it need rcd?

 

[Cirrus]

Not sure Wayne as it's in a shop. What is normal practice? He won't be using the skts to mow the lawn

 

[MacSparky]

Over that distance 2.5mm would have been adequate along with the B20 breaker...I would say RCD also as the extra sockets may supply some portable equipment, there may be different people working there at different times that don't realise your not supposed to plug that old 'Kirby' vacumn in to it....you know the one, that lovely solid metal one

 

[Andy M]

Why Not a 32A Breaker ?

Were there any correction Factors to apply which would make you want to wire an A3 radial in 4mm instead of 2.5mm, if not you are putting in an A2 radial (page 151 on site guide-16th)

Does it serve a Floor area in excess of 75 sq metres

And i don't think an RCD on the Lottery machine will go down to well with the punters, Quick design and install it to the 16th ! otherwise it will need an RCD (unless the spotty herbert in the shop can be classed as a skilled or instructed person)

 

[LukeScotty]

::i miss my on site guide, its covered in milk::

 

[MacSparky]

Why Not a 32A Breaker ?

Not on a a3 radial.....if thats what your saying andy, and what has the lottery machine got to do with rcd? cant see why that would be a problem unless there prone to high leakage current.
Already stated a run of 15m cable which is why a a3 radial would suffice.

 

[blewards]

1x 2.5mm run off a 20amp mcb surely? 4mm not a bit on the large side?

what is the cable method run?

 

[Spudmiester]

Why not put the machine(s) on switchfuse spur(s) then RCD is definitely not required !

 

[ian.settle1]

Is the any criteria set down by the lottery company

 

[Shakey]

Why not put the machine(s) on switchfuse spur(s) then RCD is definitely not required !

?????

where has this come from?

What has a switch fuse spur got to do with RCD requirements?

 

[blewards]

?????

where has this come from?

What has a switch fuse spur got to do with RCD requirements?

That one threw me as well shakey, is there a change in the 17th about spurs and rcd's?

 

[Spudmiester]

Well I feel like I am about to get shot down in flames just like Jessie James, but my point was that if the circuit supplies fuse spur outlets then whatever is conected to them is fixed equipment rather than portable, and does'nt need to disconect within 0.4 seconds !
The possability of any other equipment being plugged in and used elsewhere is removed !

As they said at Rouke's Drift, "fire at will" !!

 

[MacSparky]

Lol Spud....i see ripples on my glass of water, you know just before the tyrannosaurus rex turns up ..chews you up and spits you out

 

[Spudmiester]

Can feel em myself. Just like in Jurassic (S)park !

 

[Grae79]

i'll get ur coat...

 

[wayne]

jeeeez ! never seen something so simple get so complicated !!!!
yeah you could do 2.5mm ,but then what about this what about that ,4mm for 15 M of cable gives you spare capicity doubt some ones gonna undercut you on price and use 2.5
under 17th the fu spur would be 0.4 s disconnect
i asked about an rcd because of the 17th regs (rcbo)

 

[Cirrus]

Am doing the job thisweekend so I don't need to worry about RCD as is still under 16th Ed. Only mentioned 4mm cos I got stacks of it lying around but got heaps of 2.5 too

 

[Shakey]

Well I feel like I am about to get shot down in flames just like Jessie James, but my point was that if the circuit supplies fuse spur outlets then whatever is conected to them is fixed equipment rather than portable, and does'nt need to disconect within 0.4 seconds !
The possability of any other equipment being plugged in and used elsewhere is removed !

As they said at Rouke's Drift, "fire at will" !!

ah, can see the way you are going, you mean a switched fuse 'flex' outlet, rather than a s/o?

bit of a faff just to avoid RCD's! But of course, thats assuming the RCD was being provided for supplemetanry protection because the circuit failed to achieve its disconnection time, which just changing it to 5s is a bit of a kop out......

'course under the 17th this wouldnt apply anyway, because now its down to CPD size not circuit supplied (submains excluded!)

doing it under 16th it doesnt need an RCD, and under the 17th the sockets wouldnt need RCD if they are labelled 'lottery machines only' (although the cables supplying still might)

 

[MacSparky]

Munch Munch Munch..

 

[blewards]

ah, can see the way you are going, you mean a switched fuse 'flex' outlet, rather than a s/o?

bit of a faff just to avoid RCD's! But of course, thats assuming the RCD was being provided for supplemetanry protection because the circuit failed to achieve its disconnection time, which just changing it to 5s is a bit of a kop out......

'course under the 17th this wouldnt apply anyway, because now its down to CPD size not circuit supplied (submains excluded!)

doing it under 16th it doesnt need an RCD, and under the 17th the sockets wouldnt need RCD if they are labelled 'lottery machines only' (although the cables supplying still might)

Its a fecking minefield out there so it is Shakey

 

[EasyFox]

Shakey beat me to it.
Me I'd slap in a 2.5mm radial on a 16amp mcb & lable the socket as a dedicated socket for lottery machine only (to comply with 17th).
Or
do as above but use fused flex outlet (as already said) to comply with 16th & lable as above.

On another note......... Shakey (or anybody else) have you heard anything about the labling of dedicated sockets for 17th regs...
Was told by NICEIC assessor that a printed sticker will not suffice but an engraved accessory would only meet the requirements of the 17th....(he said crabtree & MK were mass producing them at this time)

Beaware the NICEIC assessors are now asking questions about 16th & 17th regs during assessments mine did anyway.

 

[wayne]

I have been asked to run a new circuit into a shop for a new lottery machine. Chap wants 3 x double metal clad sockets. I was thinking of running a 4mm t&e radial supply over 15 meters. What size MCB would I be advised to put into the CU?

i doubt the client would want to call an electrician everytime he wants to shift the lotto m/c so fu spurs is a non starter
3 double metal clad sockets lotto m/c needs one whats the rest for?
i refer to my first answer ,the simplest reply on this thread b20 does it need rcd?

 

[Bane]

"Fire at will"

LOL Spudmeister!!!

You didn't fare too badly though did you?

Now, the way I'd do it....

 

[Cirrus]

Well, the job is a no-go as went to look at what was needed materials wise and the board is an old Wylex with re-wireable fuses. No spare ways and only one 30A breaker with 3 conductors terminated in it. I refused the job as also the earthing system was TT with a 4mm earth and NO RCD present. Sadly, altough a shop, it is leased from the council so said if she gets them round to upgrade the board I will happily go back and do the work.

 

[Andy M]

Well all that was a waste of time then!

 

[Cirrus]

Not really, every day is a school day

 

[Andy M]

Can't you quote to upgrade the mains ?

Might be quite good to get in with the council ?

 

[EasyFox]

Could have split the tails & fitted a small cu with 30mA rcd main switch & mcb for circuit or a standard mainswitch & 30mA rcbo for circuit, then thumped in a new rod with 10mm to a MET for both new & old boards.
Why turn work away

 

[Cirrus]

I can't do the work as it's council leased. I don't want to get on their preferred contractor scheme for a few months until I have properly set up on my own. I quoted to the shopkeeper for the board upgrade but it isn't their decision. As for turning work away - I haven't either but if the council say no to the upgrade then I can't get the work. As Easyfox mentioned, it's a sound idea to split tails etc but these guys won't pay that much. They are Sikhs and want everything done at a knockdown price!

 

[Shakey]

Shakey beat me to it.
Me I'd slap in a 2.5mm radial on a 16amp mcb & lable the socket as a dedicated socket for lottery machine only (to comply with 17th).
Or
do as above but use fused flex outlet (as already said) to comply with 16th & lable as above.

On another note......... Shakey (or anybody else) have you heard anything about the labling of dedicated sockets for 17th regs...
Was told by NICEIC assessor that a printed sticker will not suffice but an engraved accessory would only meet the requirements of the 17th....(he said crabtree & MK were mass producing them at this time)

Beaware the NICEIC assessors are now asking questions about 16th & 17th regs during assessments mine did anyway.

well, i have to be honest, this is the first time i have heard of the NIC talking out of their ar*e!!!!

book says 'suitably labeled' or 'suitably identified', so what are they saying, if a socket had 'freezer only' (for example) stuck on it they would fail it on a PIR - would love to know what code they would give it, and which reg it contravened

obviously, if you were in a humid or greasy environment you would tend not to use a stick on label, but what is wrong with using it in a house

its complete shash anyway

lets say someone had a socket labeled (or etched) with 'freezer only', and they decided to re-arrange the utility room, and put the washing machine there instead - how would safety be compromised? i suppose if you then re-labelled (or re-etched it) with 'washing machine only' then the householder would instantly become 'safe' again and breathe a huge sigh of releief

you couldnt make it up

 

[EasyFox]

well, i have to be honest, this is the first time i have heard of the NIC talking out of their ar*e!!!!

book says 'suitably labeled' or 'suitably identified', so what are they saying, if a socket had 'freezer only' (for example) stuck on it they would fail it on a PIR - would love to know what code they would give it, and which reg it contravened

obviously, if you were in a humid or greasy environment you would tend not to use a stick on label, but what is wrong with using it in a house

its complete shash anyway

lets say someone had a socket labeled (or etched) with 'freezer only', and they decided to re-arrange the utility room, and put the washing machine there instead - how would safety be compromised? i suppose if you then re-labelled (or re-etched it) with 'washing machine only' then the householder would instantly become 'safe' again and breathe a huge sigh of releief

you couldnt make it up

Yep I shook my head at it aswell mate.

 

[wayne]

glad this got sorted, walking away is the prefferrred route rather than being the monkey who put it right for free

 

[Cirrus]

My way of thinking Wayne