EICR opinions

sheff6107

Just had an electrical report on a house we're buying. I could do with some opinions on these C2 issues:

• bathroom no supplementary bond evidenced shower
• double insulated singles no CPC to various switch wires
• overrated MCB for shower CCT 45 amp on 6 MM conductors
• two way lighting borrowed neutral single conductor no CPC
• outside light no CPC carried through
• sockets in garage spur off DB ground socket CCT 3 conductors in MCB

Thanks

Warwick_Hunt

sheff6107 wrote: »

Just had an electrical report on a house we're buying. I could do with some opinions on these C2 issues:

• bathroom no supplementary bond evidenced shower
• double insulated singles no CPC to various switch wires
• overrated MCB for shower CCT 45 amp on 6 MM conductors
• two way lighting borrowed neutral single conductor no CPC
• outside light no CPC carried through
• sockets in garage spur off DB ground socket CCT 3 conductors in MCB

Thanks

What opinion did your electrician give?

Sounds like the pervious work done was a bit slack when it came to earthing things.

The outside light could be shocking. :eek:

Owain_Moneysaver

Double insulated singles with no CPC (earth wire) were normal for light switch wiring and are acceptable provided they run alongside the associated twin&earth cable. They were used to save buying triple&earth cable for two-way switching.

Borrowed neutral is inconvenient if you want to update your consumer unit to incorporate RCDs.

45A MCB on 6mm conductors -- depends on the shower rating (and cable fixing methods, etc) whether 6mm cable is acceptable. It's likely that the 45A MCB provides overcurrent protection and it's unlikely that overload will occur as it's a fixed load.

Outside light no CPC is acceptable provided the outside light is double-insulated.

no problem spurring off the MCB to provide one single or double socket, provided the MCB terminals will take 3 x cables, which it will. More than one single or double socket should not be spurred off a ring final circuit.

The supplementary bonding must be corrected in the shower room unless all circuits are RCD protected -- there is no mention of RCD in that report.

Risteard

Firstly there is no such thing as double insulated cables. They are in fact insulated and sheathed. The sheath simply provides mechanical protection, although is often made of insulating material.

As for supplementary bonding not being required if all circuits are RCD protected, that is an over simplification. There are a number of conditions which must all be met for it to be permissible to omit supplementary bonding.

A cpc must be terminated at every point in the wiring.

As for the shower there isn't necessarily anything wrong with that setup presuming that the circuit breaker is providing short circuit protection to the shower, that the shower itself is not overloading the cable (it is a fixed load and therefore does not require overcurrent protection - only fault protection). So depending on the details it may actually be fine.

There is nothing wrong with having three conductors in a circuit breaker. A ring final circuit may have an unfused spur connected at the distribution board which would mean three conductors would be connected at the circuit breaker, as well as neutral and earth bars.