static caravan site

[GPack]

I've been asked to take a look at a proposed static caravan site where there is a single phase supply. It has a TT earthing arrangement. The request is to design a circuit that will feed 8 static caravans. The distance for a ring circuit supply cable to each of the vans is approx 200mtrs.
I'll just put my thoughts down and hopefully there will be someone that could steer me in the right direction.

From the Main intake, into an Swithed fuse.(would this have to be a 100A 100ma RCD?)
16mmsquared 2 core SWA set up as a ring circuit and buried at least .6mtr underground.
8 supply boxes with coin slot. 100A double pole switch, 20Amp 30mA RCD, 16A MCB attached to commando socket outlet and 3A for external light (requested by owner).
Each box would need and earthing rod.

I need to do some cable calcs just to make sure it's all ok but does it sound like I'm along the right lines? Any one know where to get the boxes from? Should I request another phase and increase the possible demand to each van? Is it ok to bring the 16mm up into the 100A double pole swtich and down to feed the next van or should I use a din rail mounted isco block?

Would appreciate a bit of advice on how to apply diversity to this please.

All comments really appreciated

 

[Guest123]

Bit difficult to advise on this one......

I have a bit of info for you, for a 60A 16mm2c ring circuit, the max length to comply with VD is 333M.


It's early and I'll have more of a think and post later.

 

[Guest123]

http://www.mcg-products.com/pdf_pages/MCG_Caravan-Marina WEB.pdf


Lots of different types of feeder pillars and equipment here^^^.

Loading wise you say 8 vans with a 16A feed to each so max demand before diversity of 128A. Will the existing installation take all this additional load, I know it's worst case but it should be allowed for.

As for applying diversity you'll need to find out roughly what each van contains circuit wise and apply diversity accordingly. Obviously it wont be the full 128A so an allowance can be made.

What is the distance from the origin to the last van on the site???, I assume the 200M you quoted was from the origin round and back again???

Would a radial suffice??? From memory and (I stand to be shot down here) the calculation for determining the OCPD for a ring circuit with regard to the installed cables being smaller is - OCPD rating x 0.67, i.e a 100A ring circuit would need a cable installed with an Iz of 67A.

The 32A ring works out to an Iz of 21A, which is about right. Like I said thats from moemory and I cant find anything to back it up so dont quote me on it.

 

[UNG]

I would imagine 16A supply to each van already has a large amount of diversity buillt in already as simple things like kettle and toaster can hit that if they are put on together in one van and that is before any heating, hot water or lighting is taken into consideration

I would check out the vans before commiting to a 16A supply to each van, the 16A supply pillers tend to be used for touring vans which tend to have a lot less reliance on mains electric ie low voltage lighting and gas for heating and cooking

Most static vans I have come across I would think that a 30 - 40A supply would be more likely if not higher. My advice would be to check out the vans before wasting too much time on a design that may be unsuitable

 

[scouse]

Check out this link they specialise in caravan site electrics

Caravan Park Electrical Services - Home

Havent used them but they look like they could help you

 

[lewlec]

hi

we do work on a site that have 8 statics on one 63amp radial and each van has a 16amp supply. havnt had any trouble with overloading....yet anyway. but these vans are fairly new ones with gas central heating.

regards
gary

 

[GPack]

Hey, thanks a lot for all the help. Really appreciated. Will contact the guy this week and get some information on the vans. The link to the MCG products is really good. I'll let you know how I get on.