workshop/shed power

[Adam_151]

Yes, presuming you have some RCD protection in the downstream board

A switchfuse may be thought of as a 1-way CU with a fuse rather than a breaker. You have the main switch, then you have your protective device for your one outgoing circuit which is usually a submain to a dist board, which is where any required RCD protection would be fitted.

 

[RF Lighting]

Yes. The 63A rating of the RCD refers to the maximum amount of current the RCD can handle. If this rating is exceeded it will not trip as that is not what it is designed to do, it will however eventually burn out, so you must not supply a 63A RCD with a fuse or circuit breaker larger than 63A.

 

[GeoffTitch]

Ahh, you make a very common mistake.

I am not surprised, but I am learning (without setting fire to the house).

 

[Taylortwocities]

I suggest you find your sparky right now, have him do the brain work (ie the things you don't know about).

 

[GeoffTitch]

I suggest you find your sparky right now, have him do the brain work (ie the things you don't know about).

If that was directed at me, he is going to cross check everything I have been drawing before telling me which bits I can do (which is probably limited to 'dig a ditch there')

I'm just naturally curious to know how and why, but hopefully wise enough to know when not to touch!

 

[JohnW2]

I suggest you find your sparky right now, have him do the brain work (ie the things you don't know about).

If that was directed at me ...

Yes, there appears to be some potential cross-thread confusion going on here, since you have been discussing here some of the things we've been talking about in the other thread!

Kind Regards, John

 

[scott25]

Am lost on my own thread

 

[GeoffTitch]

Yes, there appears to be some potential cross-thread confusion going on here, since you have been discussing here some of the things we've been talking about in the other thread!

My apologies to Scott for hijacking his thread - it just raised similar questions

 

[scott25]

Kk no worrys

 

[aesmith]

Am lost on my own thread

Back on topic (ish). For the welder you'd likely need at least a 16A breaker, maybe a 16A slow trip (type C). But it depends on the welder, you say it has a normal 13A plug, what have you been plugging that into so far?

Regarding connection at the house, my outbuildings connect as BAS described, but it's a much bigger supply that you're speaking about. I can see advantages and disadvantages to taking a smaller supply from the CU. Advantage is that you still have a single point of isolation at the CU main switch. Disadvantage you can't fully isolate the outbuildings any other way (assuming single pole MCB)

 

[scott25]

I have a blagdon power safe which is plugs into a socket in my front room with a rcd it wot u have for ponds it takes glass fuses the welder don't trip the rcd or anything

The sparky said he would run from the house cu as the load is not a lot as I would not be useing the welder and compresser at the same time


But it would be ok to run 6mm twin and earth to metal clad then with the SWA init which would then run to the shed


Am only useing diy tools

Does this sound like a gd plan

32amp MCB type C house cu
6mm t/e from the cu to metal clad box in the kitchen
6mm 3 core SWA from metal clad box to shed
Wylex RCD 8 way DP 60mA fully insulated OR
MK dual RCD board need advise on these

If I use the Wylex board should I use
MCB Type B
MCB type C
RCBO Type B

 

[ban-all-sheds]

Does this sound like a gd plan

Not if your electrician won't do it.

32amp MCB type C house cu
6mm t/e from the cu to metal clad box in the kitchen
6mm 3 core SWA from metal clad box to shed
Wylex RCD 8 way DP 60mA fully insulated OR
MK dual RCD board need advise on these

If I use the Wylex board should I use
MCB Type B
MCB type C
RCBO Type B

8 design questions.

As in

I being the person responsible for the design, construction, inspection & testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the design, construction, inspection & testing hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2011 except for the departures, if any, detailed as follows:

So therefore 8 questions which only the electrician doing the job may answer.

 

[GeoffTitch]

You do realise, from a legal concept that whole para is qualified by:

I being the person responsible for the design, construction, inspection & testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the design, construction, inspection & testing hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2011 except for the departures, if any, detailed as follows:

Define 'reasonable'

Just being pedantic

 

[aesmith]

I have a blagdon power safe which is plugs into a socket in my front room with a rcd it wot u have for ponds it takes glass fuses the welder don't trip the rcd or anything

That gives a starting point, you know the welder doesn't blow it's 13A fuse, nor does it trip the MCB for that circuit in the house. However, counter intuitively, a surge in current from the welder might trip 16A MCB even though it doesn't blow the 13A fuse, hence the circuit for the welder might need a type C breaker.

Regarding choice of CU at the garage end, I can't see the need for a dual-RCD board if there are only four or five circuits, and if you use RCBOs you don't need an RCD at all (at the shed end).

How much of this is being done/decided by your Spark? I'm not sure if you're asking for guidance to do the work all yourself, or to understand what the spark's offering.

 

[scott25]

I would like to do most off the work run the cables dig trench etc then sparky can check all the above work test and then connect it all up like I did for my brothers gym

I would also like to buy the bits I nee my self as I work for MK I get a gd discount

So the wylex with the rcd and use mcb type b cu for the shed

Am trying to get as much info as poss thank u so much for all your help and info