SUB MAIN QUESTIONS. ADVICE NEEDED

[Nelly72]

This is what the electrician has intended to do it seems to save the client the cost of an MCCB panel.. would like to reiterate its not the way I would do it, but want to clear up if it’s compliant, regardless of how messy it may seem

 

[Nelly72]

View attachment 111394


This is what the electrician has intended to do it seems to save the client the cost of an MCCB panel.. would like to reiterate its not the way I would do it, but want to clear up if it’s compliant, regardless of how messy it may seem

I have omitted the neutrals to each point so save more lines to avoid confusion haha..

Just a quick sketch

 

[Nelly72]

This is what the client showed me that he had bought for the tails to enter from the Henley blocks, and then feed the armour to the other DBS, whilst protecting the armour with an 80A fuse

 

[westward10]

There is nothing wrong with this but it looks a bit "housebasher", apologies for this. When I do a job I like to look back and think that is a good job rather than not look back knowing there was a better more professional way. What about surge protection?

 

[oscar21]

Don't think you can run tails directly to a 3 phase MCB for the heat pump, would need some kind of main switch as well wouldn't it. Why not fit a small 3 phase board for DB3 and run the heat pump from there, maybe a type A board if it doesn't need to be too big.

Oh and BTW I've taken over the odd job over the years where the original electrician "has gone AWOL" one time he supposedly "went abroad to learn sky diving", another time the spark had "broke his leg". But those jobs had one common denominator, getting paid was a pain in the arse. Make of that what you will.

 

[plugsandsparks]

Reminds me of a large house i did, very similar. Used TPN board in plant room and fed all local loads and submains from that board. Submains were C63 MCBs, GSHP C50 from memory. As mentioned one isolator for whole property, easy to expand and does not take up huge space with fused submains.... who uses fuses nowadays, lol.

 

[Nelly72]

There is nothing wrong with this but it looks a bit "housebasher", apologies for this. When I do a job I like to look back and think that is a good job rather than not look back knowing there was a better more professional way. What about surge protection?

Can they not be fitted at each DB to protect all appliances ?

 

[westward10]

Personally I would run the heat pump from a switch fuse.

 

[Nelly72]

I had thought

Reminds me of a large house i did, very similar. Used TPN board in plant room and fed all local loads and submains from that board. Submains were C63 MCBs, GSHP C50 from memory. As mentioned one isolator for whole property, easy to expand and does not take up huge space with fused submains.... who uses fuses nowadays, lol

I had thought about a TPN board, but was wary of the fact one of the DBs the 25mm armour feeds has a 10mm shower circuit, 10mm induction hob circuit, 2 ovens, few rings circuits, few lightening circuits etc. So 63A on the armour may not be acceptable?

Do MCBs not go upto 63A max? Would the above load on the DB not potentially pop the 63A? MCCB panel sounds more appropriate as you can use the 80A MCCB to give it some more juice, but it must’ve been too costly for the client, and that’s why the spark had bought the 80A switched fuses

 

[Nelly72]

Don't think you can run tails directly to a 3 phase MCB for the heat pump, would need some kind of main switch as well wouldn't it. Why not fit a small 3 phase board for DB3 and run the heat pump from there, maybe a type A board if it doesn't need to be too big.

Oh and BTW I've taken over the odd job over the years where the original electrician "has gone AWOL" one time he supposedly "went abroad to learn sky diving", another time the spark had "broke his leg". But those jobs had one common denominator, getting paid was a pain in the arse. Make of that what you will.

Yeah that was my plan, a small board with a main switch/mcb, then out to a rotary isolator..

My sketch was a bit misleading