UK Can anyone tell me what is wrong/incorrect.

[marconi]

You are correct, Marconi got his crayons mixed up

If only it was just my crayons......

 

[Simon47]

I am no expert on the regulations but wondered whether the sixth item is that the main equipotential bonding is done remote from the cutout location.

The according to the book ‘rule abiding‘ installation should have the earth conductor from the incoming N in the cutout going only a short distance to the main earth terminal bar, and then from this bar runs a cpc conductor to the dist boards, and separate EP bonding conductors for say water and gas connected also to the bar as in this figure.

With this scheme the cpc wiring and EP wiring do not share one conductor which might be considered a possible single point of failure. Just musing….

View attachment 112486

I'd suggest the opposite.
Suppose you lose the connection between MET and CU ? Your bonding is now probably via the 0.75mm flex to the boiler. By running a connection direct from service head to CU and also taking your bonding cables to the CU, you've eliminated two connections and reduced the risk of incomplete/ineffective bonding.

 

[baldelectrician]

I do like these meters with the integrated isolator built in

I actually suggested (to SELECT) about 16 years ago when they were involved in the consultation for smart meters that these new meters should have a built in isolator

The feedback- it was refused as it would cost an extra £6 per meter.

 

[freddo]

The feedback- it was refused as it would cost an extra £6 per meter.

This is why experienced engineers should be making the regulations not brain dead office staff. Surely a separate isolator in an enclosure and the extra time required to fit it would add up to more than £6?!

 

[Simon47]

I can't help thinking the meters are an example of "a camel being a horse designed by committee"