new circuit for oven and found lots of faults

[brucelee]

Hi to all,


I went round to carry out a visual ispection before doing above and have a couple of questions if ok

Its a TN-S system Domestic 100amp main fuse , has a MEMERA 2000 ccu with only 1 side RCD protected by a 30mA 100amp RCD
there is a type 1 and b mixed breakers 40amp type b bsen60898 for shower, 32amp type 1 bs2871 for ring circuit but also discovered two radials for in 2.5mm for 1 socket in kitchen and another radial for a single supplying fridge and then onto double in front room for TV,VCR, DIGI BOX AND DVD, 16amp for a fused spur for heating controls only, on RCD protected side and 1 spare way which i am thinking of using for Oven circuit


Then on unprotected side of CCU there is a mem type 1 32amp with a radial in 2.5mm supplying double for socket in attached outbuilding for a freezer in a brick shed
then there is a 6 amp type 1 supplying whole house for the lighting in 1.0mm and also a 1.0mm supplying a bulk head light in alley way and onto another in the shed all udercover from the elements

The main earthing conductor is in 6mm it looks and is connected to a old style MET with BOLTS not very well as some of strands hanging out how do i work out by calculation if this is satisfactory do iI divide 230v by Ze to get the fault current and then do adibiatic equation ????
and will i need to upgrade it to 16mm if i install new circuit for oven

there is NO water bond that i can see but not deffo LOOKS as if there is a 6mm going to bathroom need to check
GAS bond also in 6mm
most of sockets to kitchen are spurred of ring I think
IT looks like i will be better doing a periodic first as there may be other things


and a quick press of theBS4293 100a 30ma RCD and you guessed nothing so looks knacked and will need replacement any ideas if possible to get one
also open grommets on top of ccu
is it possible to get replacement cbs for MEM2000 ccu is it eaton who supply replacements any advice with any of above would be very helpful cheers sorry its a long post chaps

questions will i have to correct all the incorrect items i have listed if i wire new circuit for oven such as
1. installing 10mm for gas and water
2. installing 16mm for earthing conductor
3 removing 32A cb for a 20AMP RCBO for outbuilding and 6amp RCBO for the lights
4. replacing RCD as its faulty is it possible to get 100amp 30mA replacement for MEM 2000 CCU or will a or 80Amp 30mA rcd suffice
5. remove the two radials for sockets that have 2.5mm current carrying capacity exceeded and connect into own 20AMP CBs or RCBO if not on protected side
6. fit closed grommets to Horizontal top surface or enclose wires in conduit CABLES clipped DIRECT to wood then into CCU
any advice greatly appreciated cheers

 

[SirKit Breaker]

Re: new circuit for oven and found lots of faults etc with a visual

Not sure what you are doing or have done.

The way i read your post is that you have been asked to fit a new circuit for an Oven.
You have carried out a visual inspection free of charge
You are under the impression that before doing the oven circuit you have to right all the wrongs.

Your responsibility is to ensure that a new circuit you fit is compliant with the current regs. You dont need to fix everything else to do this.

It is wise to advise customer of problems, but to be honest if i asked someone to come to my house and fit a cooker circuit and he presented me with a list as long as my arm of electrical work needed doing i would tell him to off.

If the electrical installation is a pile of the preverbial then fit a shower CU with RCD main switch and an appropriate MCB for the oven. Connect to the supply with a Henley block, you have therefore not had anything to do with the existing installation, so any problems with it are of no concern to you. The main bonding must be present but if it undersize and not practical to upgrade then this is acceptable but must be noted on the EIC. If you need to fit bonding due to it being missing then use 10mm.

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

 

[brucelee]

Re: new circuit for oven and found lots of faults etc with a visual

Not sure what you are doing or have done.

The way i read your post is that you have been asked to fit a new circuit for an Oven.
You have carried out a visual inspection free of charge
You are under the impression that before doing the oven circuit you have to right all the wrongs.

Your responsibility is to ensure that a new circuit you fit is compliant with the current regs. You dont need to fix everything else to do this.

It is wise to advise customer of problems, but to be honest if i asked someone to come to my house and fit a cooker circuit and he presented me with a list as long as my arm of electrical work needed doing i would tell him to off.

If the electrical installation is a pile of the preverbial then fit a shower CU with RCD main switch and an appropriate MCB for the oven. Connect to the supply with a Henley block, you have therefore not had anything to do with the existing installation, so any problems with it are of no concern to you. The main bonding must be present but if it undersize and not practical to upgrade then this is acceptable but must be noted on the EIC. If you need to fit bonding due to it being missing then use 10mm.

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

Cheers mate
I know i am not under obligation to right all the wrongs, just to make sure that the proposed circuit has to comply with regs and not affect the existing. thanks for the advice mate about installing seperate CCU for the oven circuit

the circuit required for the new oven is for a fan assisted 3250Watt oven so has to have own circuit and there is no existing cooker circuit. if i do this i will have to replace RCD as i cant just leave it faulty as there will be no protection and should be isolated if faulty

Its the the mother in laws so I would like to ensure its not affecting there safety and have noticed lots of things the main bonding to water missing, gas undersized ,current carrying capacity exceeded socket used to supply outdoor mobile equipment not rcd protected and current capacity of cable could be exceeded because of 32AMP CB and no rcd, there are loose connections, damaged sockets etc etc top of CCU does ntot meet IP4X

they are on holiday at minute so will tell them about all i have found and leave it up to them.

what about the undersized EARTHING conductor its 6mm connected from CCU to a old style MET with bolts and strands terminated round the bolts hanging out then then connected through about 6 strands of the suppliers BARE armour of the SWA not sleaved or insulated is this OK
cheers Howard mate

 

[sythai]

Been having a read of your post.... definately best option, split tails, henly and seperate CU - very common job, must do one like this every other week.

Just curious...

and then do adibiatic equation

not sure what this is could someone help me out

Cheers then,

Sy

 

[GStueyXR]

Been having a read of your post.... definately best option, split tails, henly and seperate CU - very common job, must do one like this every other week.

Just curious... not sure what this is could someone help me out

Cheers then,

Sy

Equation for working out minimum size of circuit protective conductors.

Check out 7671, it's all in there.

 

[sythai]

right I see cheers then......... thank you just never heard that term before

 

[brucelee]

to do this work does the 6mm earthing conductor need upgrading to 16mm
and i would like to know if its possible to get a replacement for the 100Amp bs 4293 30mA ive found a 80Amp version but not the 100amp

 

[GStueyXR]

to do this work does the 6mm earthing conductor need upgrading to 16mm

Yes, definitely.