How the CPCs are connected? How would you code the fuseboard?

zvspark · Oct 27, 2022

Hi guys.
Can someone explain what is this? Where are the CPCs connected? I think the black cable connected to the MET have something to do with it.How would you code that?

loz2754 · Oct 27, 2022

The CPCs are the metal conduits.
If there is continuity to the each point on the circuit, then no code. Otherwise C2 for lack of adequate CPCs.
The black earth wire may be the earthing conductor, but this will need confirmation.

westward10 · Oct 27, 2022

Without seeing behind that board it is impossible to say.

SparkySy · Oct 27, 2022

That is an MEM red spot board I think the conduits are the earth if they are metal!
I took one of those out only 2 weeks ago and swapped it for a Fusebox!
I agree with @loz2754 should check at the sockets and lights / switches if the conduit is continuous,

zvspark · Oct 27, 2022

loz2754 said:
The CPCs are the metal conduits.
If there is continuity to the each point on the circuit, then no code. Otherwise C2 for lack of adequate CPCs.
The black earth wire may be the earthing conductor, but this will need confirmation.

No cpc continuity on 75% of the accessories , you're right. But now what is the remedial action for that?

loz2754 · Oct 27, 2022

It may be possible to pull a new single core CPC cable through the conduits. Though very doubtful.

zvspark · Oct 27, 2022

SparkySy said:
That is an MEM red spot board I think the conduits are the earth if they are metal!
I took one of those out only 2 weeks ago and swapped it for a Fusebox!
I agree with @loz2754 should check at the sockets and lights / switches if the conduit is continuous,

Did you swap the CU only or did a full rewire? And if CU only, did you use the same metal conduits for CPC?

loz2754 · Oct 27, 2022

Sometimes I've had success in similar situations with loosening off the bushes where they enter the back boxes, cleaning, and retightening.

loz2754 · Oct 27, 2022

Of course, it's probably long overdue for a rewire. I would be doing my best to convince the client of this.

SparkySy · Oct 27, 2022

@zvspark said
Did you swap the CU only or did a full rewire? And if CU only, did you use the same metal conduits for CPC?

I was very lucky someone had already pulled in a separate earth conductor and insulation resistance were all still good! I guessed that the installation was rewired in the mid-late 80's but for some reason the cu was not upgraded!

westward10 · Oct 27, 2022

That left side conduit looks like it is terminated through at least two entries by the look of it.

Petej999 · Oct 27, 2022

loz2754 said:
The CPCs are the metal conduits.
If there is continuity to the each point on the circuit, then no code. Otherwise C2 for lack of adequate CPCs.
The black earth wire may be the earthing conductor, but this will need confirmation.

Are the conduits joined througout the installation?? maybe they hsve used the conduits for cps