consumer change

[waynelester]

hi im after a bit of advice. i intend to change a domestic consumer unit and use this as a test job for registration. i am not worried about doing the job or the testing what concerns me is the existing system. on inspection i have found a few concerns and am not sure if these have to be put right or can be identified on the certificate.examples are no fire alarm,bonding to water main 6mm,one circuit for all lighting,cable to shed not swa and not sure if buried properly any help greatly appreciated.if all faults have to be put right when job will become much larger

 

[philip962]

before you carry out any work advise the customer about the faults found if any spark does a cu change without doing the bonding they are crap and not doing a proper job also test before you change saves a lot of time.

 

[Sintra]

Only new or refurbished dwellings require fire detection so no need to mention.

For TN-S or TT systems the csa of main protective bonding conductors must be a minimum of 6mm and not be less than half the csa of the main earthing conductor. 544.1.1 so again might not be a problem depending on supply arrangements.

 

[SirKit Breaker]

Hello,

My assumption is that this domestic CU swap is in a normal domestic residence, not a HMO or hostel or hotel type building. If so then this is what i would do.

Fire Alarm, there is no requirement under the wiring regs to have one, so this is not a problem.
6 mm bonding is OK if, The meter tails are 16mm, and the main earth is 10mm. But only if the cutout fuse is 80a or lower. If it has a 100a fuse then your tails need to be 25mm, main earth 16mm and bonding 10mm, so you should upgrade it, the get out clause is that if it is not practical to upgrade, then it can be noted as a departure on the EIC and you can keep the 6mm, however upgrade is always option 1.

The shed wiring, you can only comment on what you can test and inspect, so if it tests OK but you are not happy with how it is installed or what type of cable is used then this should be noted in the comments box on the EIC. If it is unsafe to re energise then advise your customer accordingley, and quote to put it right.

As long as you do all you can and you leave the job safe, you will have no problems on your assessment.

If you are upgrading to the latest spec protection then you are improving on what they had, so it must be safer anyway.

Cheers..........Howard

 

[pushrod]

Not aware of any regulation that says you should have a mains fire alarm in a domestic property or that the lighting must be on two circuits.

 

[ian]

C.U changes as long as you do an inspection first. The first thing that you need to remember is that you are not responsible for every circuit leaving the C.U you are only responsible for the C.U change, however, unsafe circuits should not be re connected.

6mm bonding is ok, as this was the size it was required to be when it was installed. If you find that there is an open ring circuit then de rate the breaker from 32 to 20 amps and make a note on the EIC and tell the customer. They will probably want you to sort it.

The lighting circuit is no problem, but I always make a note on the EIC.

The cable to the garage is not a problem again. If its buried you want be able to inspect it, so all you can do is test it, and if it test ok then make a note on the EIC that you don’t know about the installation method. However, if its obvious that its only buried a few inches under the ground I would not reconnect.

There is no requirement to install smoke detectors for a C.U change.

For my last 2 inspections I have shown the inspector CU changes with these faults and a lot more to boot, never had a problem or even a comment about them.

So you should be fine, just make sure your testing is spot on.

ian