Temporary building supplies again

[cliffed]

just wondering how you guys,install temp electrics to portacabins
Seen a lot of installs on sites & at schools where I don’t think it’s correct.
Mainly earthing,& earthing conductors,or am I being over cautious,cheers.

 

[The_apprentice2.0]

I don't do a lot of it personally, but there is a standard for temp supplies, have a look at BS7909 think its tailored more to events etc but might be some help

 

[cliffed]

I don't do a lot of it personally, but there is a standard for temp supplies, have a look at BS7909 think its tailored more to events etc but might be some help

Ok

 

[Nigel]

As per Section 717 of BS 7671:2018.

 

[cliffed]

As per Section 717 of BS 7671:2018.

Agree,but I haven’t seen that being done on sites

 

[Deleted member 26818]

A lot of Portacabins seem to come pre-wired with commando sockets to link them together.

 

[cliffed]

A lot of Portacabins seem to come pre-wired with commando sockets to link them together.

Yea,more intrigued by the supply & Main bonding to it

 

[driverman]

I'm under the impression that temp supplies have to be TT earthing.
DNO's usually insist on TT earthing for temp supplies. They will not provide PME for temp supplies.
Even if Perm supply, aren't porta cabins classed as temp building as they are movable?

 

[cliffed]

I'm under the impression that temp supplies have to be TT earthing.
DNO's usually insist on TT earthing for temp supplies. They will not provide PME for temp supplies.
Even if Perm supply, aren't porta cabins classed as temp building as they are movable?

Thanks,seen so many not tt,& agree Pme should not be used.

 

[Nigel]

Agree,but I haven’t seen that being done on sites

I agree. We test a lot of steel shipping containers and they are almost never done correctly. Usually connected to a PME earth is the issue.

 

[Nigel]

A lot of Portacabins seem to come pre-wired with commando sockets to link them together.

Need PAT testing then.

 

[Deleted member 9648]

TT is not always required. TNS is acceptable. A TNCS supply to a transportable unit can be used where the installation is under the continual supervision of a skilled or instructed person. This may be the case in the units you have observed not on a TT

 

[Nigel]

I'm under the impression that temp supplies have to be TT earthing.
DNO's usually insist on TT earthing for temp supplies. They will not provide PME for temp supplies.
Even if Perm supply, aren't porta cabins classed as temp building as they are movable?

Any transportable unit will need an earth electrode installed unless it is under the supervision of 'skilled or instructed person(s)' in which case the PME can be used.

Construction sites also need to comply with Section 704 as well as 717.

 

[Deleted member 9648]

Any transportable unit will need an earth electrode installed unless it is under the supervision of 'skilled or instructed person(s)' in which case the PME can be used.

Construction sites also need to comply with Section 704 as well as 717.

A transportable unit connected to a TNS earth will not need an earth electrode or to be under supervision.

 

[Nigel]

A transportable unit connected to a TNS earth will not need an earth electrode or to be under supervision.

I know. Thanks for that.