Looking for opinion on whether this scenario is compliant

[Wilko]

Hi - agree.
But any L-E faults before the CU's RCDs will have to clear via the service fuse. And with TT its likely it won't clear and there's risk the installation E could rise. Case of L tail flapping about inside AMD3 CU for example (very unlikely and why tails glands and good workmanship always needed).

 

[Ian1981]

Hi - agree.
But any L-E faults before the CU's RCDs will have to clear via the service fuse. And with TT its likely it won't clear and there's risk the installation E could rise. Case of L tail flapping about inside AMD3 CU for example (very unlikely and why tails glands and good workmanship always needed).

I like to install an S type rcd rather than the main switch if using a dual rcd board but that’s just my preference on TT arrangements.

 

[westward10]

This is a plastic CU doesn't need a 100ma main switch. The rcds in situ provide additional and fault protection as already stated.

 

[Ian1981]

Yes agreed a plastic consumer unit takes the danger scenario of loose tails touching the enclosure causing a potential hazard, out of the equation

 

[Adam W]

Yes agreed a plastic consumer unit takes the danger scenario of loose tails touching the enclosure causing a potential hazard, out of the equation

... Although of course there's still the risk of the CU catching fire.
I had a quick leaf through the new OSG in the wholesalers the other day - there's bit in it about countering precisely that situation, but I can't remember the exact details.

 

[rompling]

The higher zs is fine, and dealt with by the application of rcds for fault protection, and in this case since they are 30ma they will also provide additional protection. The curve ball is the 2.64 ohm L-N....generally we assume that if R1+R2 is good then R1+RN would be as well....since the CSA of cpc will be less than or equal to the neutral...but ring finals aside, what specific tests are mandated to check this? Could well be a loose neutral connection, but how are these tested?
Often hear circumstantial evidence that it's always neutrals that burn out or are loose....is it because a loose l or cpc gets picked up during r1+r2 testing, but those pesky neutrals fall by the wayside? Just a thought....

Totally agree