Wiring a static caravan, a touring caravan, and a site office

[BillyTheSparks]

YO!!

Right senario I have, Main house is to be demolished on Monday.

There is a new Temp meter and supplyboard (hager 17th board with 1x 63a MCB on one RCD) via a SWA to feed the house for the rest of the week. And 1x 63a MCB on the other RCD to feed the static caravans own C/U Again via SWA.

Plan is to remove the house SWA on Sunday and re-route to the portacabin/site office so that demolition can take place first thing Monday.

All good so far.

Now the problem being that next to the static caravan there is a touring (towable) caravan to act as a bedroom for the kids.

This second caravan is not phyisically attached to the first and has its own CU.
The frame of the second is metal and is earthed to its CU.
The second will be supplied from the first via a commando socket outlet on its own circuit.

The first also has a metal sub-frame and an earth rod. At the moment it has a 30mA RCD unit which can be changed to a split load 100mA Main switch / 30mA RCD (from the old house).

So the question being should the second caravan have it's own earth rod and RCD protection wired from a non RCD protected (or from a 100mA RCD) way from the first?

Or could it be bonded to the first via a 10mm or bigger Earth cable?


Any help would be great

Thanks

 

[nickblake]

My prefered method is to rod each point for the caravan on TT systems as required in caravan supplies it is essential to keep the Ze below 200 ohm if the readings are above this you could well end up with an unstable supply thats the caravan side as supplying the caravan obviously you cant give it a full load you say it has a 63 amp RCD dont forget there is no overload on this so an MCB is required , if you change the RCD to 30ma and use 2 16 amp mcbs then this will be sufficiant to supply the 2 caravans hope this is of help

 

[BillyTheSparks]

Cheers for that Nick.

I did think that this was the case, but mind is drawing a blank tonight..... to many late nights!

The SWA is supplied from the temp board from a 30mA RCD with a 63A MCB (the same for both Circuits)

Would you also bond the two caravans together??

Thanks in advance

 

[Engineer54]

Would you also bond the two caravans together??

If you mean the rods Yes, but make sure that the rods are at least the length of the rod apart, a little more is better.
With TT systems the more contact you can make with earth the better. As this is a temporary installation try keeping the rod locations in a damp condition with regular watering, and maybe a little chemical treatment...

If you mean bonding the frames of the caravans together, ...don't see why you can't, ...i probably would!!!...lol!!

 

[truckster]

I would take the supply out to a 2 gang pitch box on a TT with a delayed 100mA RCd 63A MCB, then each van fed from it's own socket 30mA 16A MCB

 

[BillyTheSparks]

Thank you for your excellent suggestions. I will be using both ideas from both E54 and Truckster on wiring this little jobby.

Cheers Nick for your mind budging on the earth rods!!


Thanks for your help

Billy