Mobile Trailer wiring

[looman]

Hi Chaps first post time!

My firm makes portable toilet trailers and although they come in section 717 17th edition it is unclear to me at least weather they should have an earth rod as well as a site supplied earth via a 16a cform?
I put one on before from the main earthing terminal via the chasis to the rod but others dont...?
some sites insist on it others it seems argue it is a bathroom so should be double insulated lighting etc ( although they dont seem to have ip rated fittings!)mmmm.
any ideas who is right?
cheers

 

[looman]

Come on chaps give me some assistance here pls.
I noticed that as the trailers that have been wired by others are mostly glassfiber and wood panels with plastic piping so in theory they would be insulated so the earthing on the lighting and double insulated pumps unit are not used? If they have a double insulated fitting they are not earthed. so does the cable still hace to contain an earth link through its entire length or is a two core flexable cable sufficent?
think i would go for the earth and belt/braces but what do i know!

 

[desertbootz]

Go on then, I'll have a stab at it...

Looks like it may depend on where yr getting yr supply and/or what system is applied within the portable unit??

Looks like you either need an internal TT or TN system within the bog or isolating transformer as part of the bog installation. Either way, and I may very well be talking the kind of stuff yr clients will be putting down the loo, I would think it depends on whether yr Earth fault loop impedance is within limit for ADS?

 

[looman]

Thanks for the reply,(there is more than me on this planet !.. ish.)

I have decided to run earth to everthing just in case and still fix an earthing rod incase we get chucked off site (cheaper than the revisit). 30 mA trips on everything and the earth is as big as I can get