Caravan or Mobile Home? Which one is it.......

[Adrian Sadler]

Hiya all

What we have is a holiday home site type effort where there are 13 caravan type looking units of accommodation.

They do not have towing facilities nor are wired for running lights while towing.
They are sat on wind down legs for adjustment.

Mobile Home - A transportable leisure accommodation vehicle which includes means for mobility but does not meet the requirements for construction and use of road vehicles.....

I thought caravan and therefore caravan site but the more I read it - Its a mobile home.

The issue we were having is that the site supplies are PME.
This is ran all the way to these homes.

The homes are fed from a DB attached to each of the outside of these homes (only accessible with tools) - which in turn feeds the internal manufactures CU.

Now - they have installed via the external DB - a 13a IP socket for hot tubs - on RCBO.

Now people are getting electric shocks from the hot tubs.............

4 other firms have been out to site and said there is nothing wrong with the electrics and it must be the tub. They have also stated that it is not classed as a caravan site so section 707 (i think) does not apply.


Here's my view.

Option 1
External DB main sw will be changed to 100ma type s D.P switch. Install MCB to feed the van and leave the hot tub supply on RCBO.
Divorce the earth at this DB and turn into a TT system therefore both the home and tub are same potential as earth and the shocks will go away.
Use the PME on the armouring for decent protection.

Option 2
Unsure on this one....
Leave the Homes on PME and just divorce the earth at the tub end and rod tub only.
The issue I see with this is that you can touch the tub and the metalwork of the home at the same time. If you can do this then IMO there's risk of a shock again.

If we look at the mobile unit regs section 717 - PME shall not be used unless a) its continuosly under supervision of skilled or instructed people and b) means of earthing is tested before connection.

Now a groundsman wouldnt fall under this........

After any ideas or opinions please as this ones doin me head in - along with site owner.

PS - I have chosen option 1 above and applied to one home - no shocks

 

[Wilko]

Hi Adrian - a couple of thoughts for what it's worth

In post #1 you mention 13 caravans, and some trouble-maker hot tubs. Is a single 100A supply going to be man enough for that lot?

The "is it a caravan" question - when I read Section 708 it's about locations, is the location a caravan or camping park or similar location. To get picky you could ask local council to tell you the approved use of the land. To me, the diag you've attached doesn't look like a typical domestic supply to a house or a street, just sayin.

If folks are getting tingles in/out of hot tub then as RB says in #8 there is likely a pd problem between stand-on-earth at the tub and the incoming CPC. We know the fix for this, and it's a requirement (I think) of 708.553.1.14.