Electrician Jobs West cambs - outdoor supply for hut 40A+ on 63A socket

[Chris S]

Hi,
My inlaws have a new garden hut arriving in three weeks to the bottom of their garden which is around 103m from the house. It has various electrical appliances including a 8.4kw electric shower (!). The company making them do an EIC measured on their supply before transporting it to us. The hut has a 63A waterproof appliance plug underneath it for the hook up. The hut is more like a caravan in that it has metal wheels and chasis underneath, but it does not have metal sides. As we have livestock in the field, I want to make sure it is well grounded.

We have a groundworks team coming in a weeks time to open up trench for the water supply and pressure sewer. I need an electrician to design/advise the conductor sizing for the long run, and who can then come in and make up the socket outlet, connect at DB & minor works (?) certify it. I would like to order up the SWA and lay it to the DB to their design.

I would like to finish the supply on a wooden post in a 63a socket. I have ordered a 4m 230v 3 pin 63a extension lead (16mm H07 cable) IP67 Rated for final hookup to the hut from said socket.

We are proposing to join the distribution board in an outbuilding which is a 63A 30ma main breaker with 2 ways clear. This is fed from the main DB on a B40A MCB via. T+E. There have been no alterations to this board since it was rewired in 1996, so no readings or test cert that I am aware of, although there are recent inspection stickers. Site visit no problem. Attached photos of both boards.

I am trying this group as I don't want to get a coyboy who underspecs the submain and then find myself having to excavate again down the line. We used to use Holgate and french of Ely but they have got bankrupt.

It is both high current and long distance so we anticipate quite costly. I do not understand if I should be asking for just the provision and test of *just* a 63A socket outlet, limited to 40A at the head end, or if anything further then needs to be done once the hut arrives. I see mention on the IET sites about needing a pitch RCD and local TT-supply for caravans.

If you are interested and suitably qualified please get back to me on the direct message and I'll PM you my mobile.

Many thanks,
Chris

 

[Chris S]

I've attached a drawing I made with photos of the distribution boards.

 

[Pete999]

Hi,
My inlaws have a new garden hut arriving in three weeks to the bottom of their garden which is around 103m from the house. It has various electrical appliances including a 8.4kw electric shower (!). The company making them do an EIC measured on their supply before transporting it to us. The hut has a 63A waterproof appliance plug underneath it for the hook up. The hut is more like a caravan in that it has metal wheels and chasis underneath, but it does not have metal sides. As we have livestock in the field, I want to make sure it is well grounded.

We have a groundworks team coming in a weeks time to open up trench for the water supply and pressure sewer. I need an electrician to design/advise the conductor sizing for the long run, and who can then come in and make up the socket outlet, connect at DB & minor works (?) certify it. I would like to order up the SWA and lay it to the DB to their design.

I would like to finish the supply on a wooden post in a 63a socket. I have ordered a 4m 230v 3 pin 63a extension lead (16mm H07 cable) IP67 Rated for final hookup to the hut from said socket.

We are proposing to join the distribution board in an outbuilding which is a 63A 30ma main breaker with 2 ways clear. This is fed from the main DB on a B40A MCB via. T+E. There have been no alterations to this board since it was rewired in 1996, so no readings or test cert that I am aware of, although there are recent inspection stickers. Site visit no problem. Attached photos of both boards.

I am trying this group as I don't want to get a coyboy who underspecs the submain and then find myself having to excavate again down the line. We used to use Holgate and french of Ely but they have got bankrupt.

It is both high current and long distance so we anticipate quite costly. I do not understand if I should be asking for just the provision and test of *just* a 63A socket outlet, limited to 40A at the head end, or if anything further then needs to be done once the hut arrives. I see mention on the IET sites about needing a pitch RCD and local TT-supply for caravans.

If you are interested and suitably qualified please get back to me on the direct message and I'll PM you my mobile.

Many thanks,
Chris

A new circuit and a MNWC don't compute Chris, Firstly you need to employ someone who knows what they are doing, to design and install the electrical supply to the new building.

If I was being honest it's a bit late in the day to start worrying about the electrical supply, of this size.
The Electrician will need to evaluate the current set up to assertain if what you require is feasible, for example have you approached the DNO to see if the supply to the existing dwelling is large enough to cater for the extra power consumption?

 

[Cadgey123]

Phone a couple of companies and tell them the information above and get a few quotes to compare. There is nothing hard involved.

You sound like you have knowledge of certain aspects of the electrical trade, so no doubt you will discover if the companies are up to scratch.

 

[Wilko]

Hi Chris and Welcome to the Forum !
For your new building with an electric shower and probably cooking and heating (as there's no mention of gas?) I can see why the manufacturer has put the 63A connector. I'd be thinking to divide your service directly after the meter and run the new service from a fuse switch there. Just a thought

 

[buzzlightyear]

welcome Chris ,what you are thinking his not are thinking . you need a new feed from
DNO cut out area direct to the new hut because of the loading .
you need a good spark to design it for you having 103mtr of cable to the new hut .
you are looking at 16mm cable for that to the hut.

 

[Strima]

You would need some measurements done at the source of supply and the DB you are proposing to come from as this will impact on the cable design.

I would be inclined to go down the route of having a fused supply, as mentioned before, split off from your meter and have a caravan style distribution circuit at the hut end. As this unit has wheels and a shower I would be treating it as a caravan.

 

[davesparks]

welcome Chris ,what you are thinking his not are thinking . you need a new feed from
DNO cut out area direct to the new hut because of the loading .
you need a good spark to design it for you having 103mtr of cable to the new hut .
you are looking at 16mm cable for that to the hut.

I think it'll be a bit bigger than 16mm at that distance, on a rough calculation on volt drop based on the 40A mentioned I get 35mm cable minimum.

 

[buzzlightyear]

delete

 

[Strima]

Why would you use 90c SWA and not 70c?

 

[buzzlightyear]

sorry strima, I was using Doncaster cables calculator having no book to hand.

 

[Chris S]

Thanks for the replies. All seem to be agreeing it's a caravan rather than a socket outlet, so that helps.

No plans to randomly order up the SWA cable from an internet forum comment, but thanks, will wait until I've spoken with someone willing to do the design for me (No PM's so far). The groundworker is going to open up trenches week of 16th October and hoping to close up that Friday, so there should be plenty of time. If not I can keep the sheep out and leave it open another week. I'm doing the plumbing so it won't be moving very quickly.

I have learned plenty from this forum, just to identify what there is. There is a Henley service connector block after the meters, before the first consumer unit, but no isolator other than the DSO's fuse, so adding another CU at that level would need some coordination. It's easier to run cables from the second CU as the outbuilding is partly in the right direction, and unplastered, and it follows my runs for the water. But the T+E between may not be sufficient - looks like good cooker cable to me.

I tried to draw a circuit diagram of what is happening on the DSO side at this house and it looks like a pretty weird setup. There is a manual ticking VENNER ERO28P timeswitch providing a small-diameter signalling input to the modern "Multi-rate single phase watt house meter". But there also looks to be what I can only guess is a switched live from same VENNER switch that is in parallel to the modern meter and joins at the henley block (or maybe I misunderstand the purpose of that cable). I'm no expert but I don't see how they could measure any kwhs when that wire is switched live, guess that's a DSO problem! I'll send a pic if interested...

 

[davesparks]

That timeswitch will be sending a signal to the meter to tell it when the off peak period of the economy 7 supply is.

Presumably the house has night storage heaters?

 

[Chris S]

That timeswitch will be sending a signal to the meter to tell it when the off peak period of the economy 7 supply is.

Presumably the house has night storage heaters?

It's Oil fired now, they might well have gone in the 1996 rewire.

 

[Chris S]

Found someone reasonably local to come out and look at it on Thursday. Thanks for looking.