advice

[domestic spark]

hello, got a job needs a supply outside to a log cabin for a hot tub, two socket outlets and one light.

what i was thinking of doing was running 10mm 3 core armoured.

i was goin to install a ccu next to original with a 30ma rdc. split the tails, henley block.

run the armoured 600mm underground 15m max, and once in the log cabin gland off and put another 3 way consumer unit again with 30mA protection.

then in t&e 1.5 wire a swich and light

in 2.5 t&e put two sockets in.

and off the same board wire in the hot tub.

will 10mm 3 core armoured over 15m be ok?

cheers guys!

havent done much armoured. if you know a better way, step by step it thankyou!

advise much appreciated!!

 

[Hawk81]

Since coming on UK electrical forums, i've been amazed at the tendency to TT everything that involves a sub-main cable to shed or garages and the like, WHY?? ....I honestly can't understand the reasoning behind it!!

It took years to get the majority of the old domestic TT systems converted to PME, by the old leccy boards. Some are still being converted to this day. And here you are creating ''More'' TT systems, ...mostly i fear, because you think it's cheaper than running a suitably sized cable or an additional bonding cable.

The fact is, to create a REAL TT system is far more expensive, but then many don't provide a real TTsystem, mostly you just bung a rod in the ground and think it's a TT system. In the vast majority of cases it Isn't, your relying ''Totally on an RCD device for providing earth fault protection.!!! I also wonder how many electricians know how to maintain a TT system, let alone be able to inform there clients how to maintain them.

Domestically speaking, a TT system should ALWAYS be the LAST choice of earthing system, and considered only when all other avenues have been exhausted. For those that are still under that age old myth that a PME earthing system cannot in any circumstances be extended to an out-building, really do need to understand the Reg's much better than they do now. I believe that even here on the Forum, there is clarification on this issue in one of the Sticky's.

The fact is, ...You CAN take a PME earth with your cable, when supplying domestic outbuildings even when there is water or other services present in that building. There are no rules or Reg's saying you can't either....

I have lost count how many times I have said something similar. I constantly get the reason as "The DNO do not allow you export a PME earth" this is utter rubish. they do not care.

 

[Engineer54]

I know, i have a very good friend with a DNO. He always says, to his knowledge no-ones ever asked in my region!!!
The only exception they have is for petrol stations and other hazardous area's....

 

[MarkieSparkie]

Warning: The HSE take a dim view of distributing the supply in this way and leaves the electrician open to a breach of ESQCR 2002, as you by implication are assuming DNO duty holder powers that you do not possess.

 

[Engineer54]

If your complying with BS 7671 Why would HSE Take a dim view of distributing a PME supply??

Your listening to all those scaremongers out there, that have been listening to other scaremongers, and so the circle continues!!!