Thanks everyone. I should add this installation is an insurance claim being carried out by NFU's approved contractors. Or their subbbies to be precise. My mother won't be paying for it but she has to sign it off before they'll pay out and that isn't going to happen unless its right. So if I've understood it correctly the cable should be armoured and should be a minimum of 450mm deep with tape. I doubt if its a foot deep. I'll be finding out tomorrow and there'll be a visit from the building inspector.
Definitely echo what others have said on here.........The installation is totally unacceptable. The cable should be armoured and at 450mm depth; although not necessarily in a duct (if it is armoured). Ordinary internal cable should not be used externally up the wall unless it is in a steel conduit. And if the sewage treatment unit is more than a relatively short distance from the house (sorry, I need to check the dimension, but I think it is 30'-0") it should have an RCCB next to the plant and an earth stake (regardless of PME earthing in the house). In fact, it is a good idea to have the supply from the mains (on the correct side of the meter of course) also via an RCCB, rather than through the distribution board......that way if there is a fault with the plant or the wiring, it won't trip the whole house out.
I nearly agree with all of this except the bit about internal cable (normal flex). Regardless of steel conduit this sort of cable should not be used outside. It is not designed for low temperature or damp conditions, both of which are present in external steel conduit.
I've had a word with the spark this morning. He's re-routing the cables as we speak. The cable in the duct is now armoured, it does have its own earth and RCD but it goes to an externally mounted box just above ground and exits the box as non-armoured cable without conduit and enters the fuse board through the wall. I made him take it out of the window sill and repair the hole. I rang Elecsa as well and they said non-armoured flex can be used externally and without conduit provided there are no adjacent hazards. I don't like the sound of that either but I don't know what I can do about it if he is registered with Elecsa and they say it is acceptable.
It doesn't seem right from your description....get a fully qualified sparks to look at it. Sometimes on very short runs it may be acceptable, but the cable must be rated for outside use e.g. SY cable From your description I would insist that this is in swa until it entered the building.
I won't be signing the job off until I have the spark's certificate. When I have it I'll get an independent inspection, again before signing off. If it transpires that a certificate has been issued for work which does not comply with regulations as I understand it and offence has been committed and I shall pursue it vigorously.
