16mm T & E flat supply

[craig1000]

Existing supply is 16mm T & CPC to 2nd floor floor flat from ground floor communal CU! Fed via BS1361 60amp, after the incoming mains have been split between 2 meters! Incoming main fuse only 60amp too!
Loop reading @ 2nd floor CU is 0.12 & PFC is 1.87kA respectively!
Bit of an existing mess to be honest IMO, there are 2 6mm single cpcs running up from the MET, both go to the flat CU, there is then from the flat CU another 6mm cpc going to water under kitchen floor!
No gas bond at present in the flat itself but gas is bonded in ground floor lobby from MET.
Main water supply is also bonded in attic above communal lobby & then splits itself to go up into 1st & 2nd floor flat!
My view is I can leave how it is as the water is bonded as a whole into the building, does it then need bonding again entering each flat? If not then gas is already bonded on entry to the building, both flats have separate metered supply & separate bonds from MET to each gas meter!
This being the case then the 16mm T & E suffices as a supply cable only does it not? Or if needed could the 2 * 6mm single cpc's be utilized? Pig of a run to alter anything & would like to avoid if poss for cost reasons for customer! If it has to be done then so be it & customer understands!

 

[shocking_eg]

what are you doing to require these changes ? just a condition report or something ?

 

[Deleted member 26818]

I'm assuming that the PFC is the PEFC, what's the PSSC?

 

[craig1000]

Yeah have just done a condition report on it, cafe ground floor then entrance round the back with communal staircase leading up 2 levels to a flat each level!
The existing set up is a mess but its trying to sort out what is just rough & what is against regs etc! Still new to EICR's i'll admit so hence the post! As old & clearly designed & installed to probs the 15th its determining things! My understanding is that I cant fail things for not being to current regs when they were designed to previous ones etc unless clearly dangerous, in this instance I dont see it is but am also wary of leaving just a 6mm cpc in a 16mm T&E as a supply cable & no additional CPC
This is amongst many other things that are a mess but dont break regs etc
I am researching through my books & dont just expect people to do my work for me but help is appreciated, I cannot learn these regs books over night etc & if I dont get out doing the work I also will not learn! Got my 17th, booked in for testing & have over ten years commercial install experience but none really at the form filling in etc on any install especially domestic!

 

[craig1000]

The PFC reading stated is the potential fault current, the higher of the two readings PEFC & PSSC.

 

[Ohm4]

Reg 544.1.1 will answer your question along with Table 54.8
all on page 167

Just done 17th so good practice for me to look

And yes the 16mm and 6mm CPC should be ok (i think)

 

[craig1000]

Cheers Ohm4, appreciate that, I have been looking & am happy putting in the work but in all honesty i am struggling to juggle looking up things I don't know, & all the other aspects that now come with being out on my own, doing the site work & the paperwork! Point in the direction of the answer is all I needed! thanks again!

 

[Engineer54]

Existing supply is 16mm T & CPC to 2nd floor floor flat from ground floor communal CU! Fed via BS1361 60amp, after the incoming mains have been split between 2 meters! Incoming main fuse only 60amp too!
Loop reading @ 2nd floor CU is 0.12 & PFC is 1.87kA respectively!
Bit of an existing mess to be honest IMO, there are 2 6mm single cpcs running up from the MET, both go to the flat CU, there is then from the flat CU another 6mm cpc going to water under kitchen floor!
No gas bond at present in the flat itself but gas is bonded in ground floor lobby from MET.
Main water supply is also bonded in attic above communal lobby & then splits itself to go up into 1st & 2nd floor flat!
My view is I can leave how it is as the water is bonded as a whole into the building, does it then need bonding again entering each flat? If not then gas is already bonded on entry to the building, both flats have separate metered supply & separate bonds from MET to each gas meter!
This being the case then the 16mm T & E suffices as a supply cable only does it not? Or if needed could the 2 * 6mm single cpc's be utilized? Pig of a run to alter anything & would like to avoid if poss for cost reasons for customer! If it has to be done then so be it & customer understands!

Each flat (and the cafe come to that) has it's own separate supply and therefore needs it's own bonding to water and gas services as they enter the individual flat!! It doesn't matter what bonding arrangements have been made to the services at the main intake position of the building.

 

[craig1000]

The gas is metered & bonded existing at the entrance to the communal stair case near the main intake position 2 * separate supplies & gas meters & then each runs up separately into each flat & direct to each flats boiler! Would you suggest I remove existing gas bonds & instead run new ones from each flat CU?
In which case I would need to add an additional CPC running with each 16mmT&E supply cable to each flat CU also if it was going to be used for bonding from the flat!
This is what i initially thought but don't want to be deemed to be doing work for the sake of it or that isn't required!

 

[shocking_eg]

If its already bonded at the intake and its sufficient why would you run it from each flat instead ?

 

[craig1000]

I was referring to the previous comment by enginer54 is why i suggested that as it what he appears to suggest! I shall look further into it!

 

[shocking_eg]

That seems a totally pointless task

You will end up making the resistance higher with the longer cable runs

And it all goes back to the same place anyway !

 

[shocking_eg]

Where are they bonded? At the meters ?

Or are the meters next to each individual flat ?

 

[craig1000]

I am not disagreeing with you shocking lol & the last thing I want to do is replace if not required too, at the same time I want to make sure it is correct! Not saying it isn't now I just want to do my research to confirm to leave as is or change!

 

[craig1000]

At the meters which are just inside entrance lobby to communal staircase on ground floor, 1 flat on 1st floor & 1 on the 2nd floor!