MCB Wiring doubt

[smudger]

Hello Proper Electricians.

Hoping for a bit of advise. I'm a plumber with Part P domestic qual, but haven't done a lot since taking exams. Just fitted a kitchen and when it came to installing microwave, discovered it was 3.4kw with 3.25kw cooker and gas hob therefore about 25a. Think regs ok with wiring both through existing 45a dp as within 2m, but don't want appliance on 45a fuse. So thought best option to put on individual 16a mcbs. So far so good I hope. However, started to doubt myself on wiring as I haven't done one for ages and can't find wiring diagram in my notes (also can't find my osg). I have taken two radials to mcbs and two cables to CU's for appliances. Am I right that I connect all earths to earth block, neutrals to neutral block, incoming lives to top of mcb, outgoing to appliance from bottom? If I'm well off I let me know and I will speak to electrician tomorrow, but if anyone knows where I can see wiring diagram I would be really grateful.

 

[telectrix]

to be honest, mate, you're frightening me with that post. FFS get the spark in.

 

[Moses]

Yes but no, but yes but no, but yes but no....................................

 

[smudger]

lol, first bit i did was under instruction Teletrix, but your probably right. I'll get him in.

- - - Updated - - -

lol, first bit i did was under instruction Teletrix, but your probably right. I'll get him in.

 

[Dan the spark]

Hi smudger, just out of interest mate. Is your part p defined scope?

 

[smudger]

No its not Dan. But to be honest I normally just pay my spark to do all electrics as its cheaper and it takes me ages. Normally stick to adding the odd socket and connecting my ufh. Run out of time on this job and wasn't expecting such a massive microwave.

 

[Dan the spark]

Mate it's good to hear that you hold your hands up when your unsure and get someone who does know in to do it correctly :clap:

 

[steveberry11]

plumber with Part P domestic qual

You may mave passed an exam but I feel that you would not be able to prove competence.
Do you not feel that the questions that you are asking indicates that you should employ an electrician for your sake and that of the customer

 

[telectrix]

plumber with Part P domestic qual

You may mave passed an exam but I feel that you would not be able to prove competence.
Do you not feel that the questions that you are asking indicates that you should employ an electrician for your sake and that of the customer

see post #6. he knows his limitations and has been brave enough to admit it. can't knock him for that. :grouphug:

 

[smudger]

Steve, I could definitely prove competence for everything that I do. I always test everything properly and never do anything unless I am sure. I don't don't take chances with electrics Steve. If I'm not sure I use a professional. I'm sure what I've done so far is within regs.

 

[VoltzElectrical]

Hello Proper Electricians.

Hoping for a bit of advise. I'm a plumber with Part P domestic qual, but haven't done a lot since taking exams. Just fitted a kitchen and when it came to installing microwave, discovered it was 3.4kw with 3.25kw cooker and gas hob therefore about 25a. Think regs ok with wiring both through existing 45a dp as within 2m, but don't want appliance on 45a fuse. So thought best option to put on individual 16a mcbs. So far so good I hope. However, started to doubt myself on wiring as I haven't done one for ages and can't find wiring diagram in my notes (also can't find my osg). I have taken two radials to mcbs and two cables to CU's for appliances. Am I right that I connect all earths to earth block, neutrals to neutral block, incoming lives to top of mcb, outgoing to appliance from bottom? If I'm well off I let me know and I will speak to electrician tomorrow, but if anyone knows where I can see wiring diagram I would be really grateful.

Here is a bit of friendly ADVICE. Please get an electrician to correctly calculate the load requirements of the circuit, select the protective device, determine the cable size, and install appropriately. Once installed, then test and energise then test live, certify and leave.

I respect your trade, but leave us to ours.

 

[Johnuk]

get a electrician in lol

 

[smudger]

Yeah, ok Voltz. But just because I'm not a time served electrician does not mean that I can't use the tables to calculate load, select appropriate protective devise and cable size. As I mentioned I test thoroughly according to osg etc. I know electricians that can hardly add up, so for me the maths behind it is a doddle. I am a member of NAPIT and get tested, I just don't do a lot as my time is better spent doing the stuff I do quickest. I had a moment of doubt at work today and thought I might get a bit of advice.

 

[parker56]

Fair play to you smudger for asking for advice instead of going in blind,respect to you.

 

[Dave 85]

Here is a bit of friendly ADVICE. Please get an electrician to correctly calculate the load requirements of the circuit, select the protective device, determine the cable size, and install appropriately. Once installed, then test and energise then test live, certify and leave.

I respect your trade, but leave us to ours.

As far as I can see he has already calculated that 16amp MCB's will be sufficient (which they will), that he will be drawing approx 25amps total between the cooker and microwave (which is correct) and I'll give him the benefit of the doubt by assuming he's not planning to wire the circuits in 1.5 T&E or smaller.

Your 'friendly' advice is delivered in a distinctly unfreindly tone.
Why tell him to get an electrician to do calculations when he clearly already knows what size MCB's (and almost certainly cable) to use.

Would you chastise an electrician who said he was going to replace a sink waste?