SUB MAIN QUESTIONS. ADVICE NEEDED

[Nelly72]

Hi all.

I have been asked to take over a job an electrician has started, and has moved abroad.

The house is a big mansion, with a 3PH supply, with 100A fuse on each Phase.

The electrician has ran 2 25mm 3core armours to another 2 DB’s in the mansion, and there has to be a DB fitted where the incoming supply is, bringing it to a total of 3 DBs.

In the plant room, there is also a 3PH heat pump.

However, my question is how would you all terminate the sub mains. Would you bring each phase into a Henley block, and branch off into a 80A switched fuse for the armour sub mains, and take a tail off the Henley blocks for each phase into a separate enclosure with a protective device for the heat pump, or would you fit a TPN board, and bring all armours into it + the heat pump supply?

If it’s a TPN board would you fit MCBs or MCCBs for the 25mm armours? Is there even

I’m a new build house basher, so this is abit more complex to what I’m used to, even though it’s a new build, so please go easy on me I am simply just wanting advice to keep me right.

 

[westward10]

MCCB panel board. I hope they aren't three core SWAs.

 

[Nelly72]

MCCB panel board. I hope they aren't three core SWAs.

Why do you hope they aren’t 3core armours mate ?

 

[westward10]

Ignore me I assumed the DBs they were supplying were three phase but they are obviously consumer units.

 

[westward10]

You could also use a busbar enclosure and switch fuses.

 

[Nelly72]

You could also use a busbar enclosure and switch fuses.

I think the spark had went down the route of Henley blocks and splitting out to 2 80A switched fuses, and then splitting out to a 50A 3phase supply for the heat pump, for cost reasons to save money on the likes of an MCCB panel.

Now, I know it will look like spaghetti junction and what not with loads of 25mm tails, but is there any regs that state this isn’t a compliant method of supplying all the sub mains.

Would like to be clued up on this so I can give client all the options, and give me peace of mind that if they go with the cheap option of Henley blocks, then atleast it’s compliant.

Thanks so much for your time replying to the thread

 

[westward10]

It is all a bit ad hoc.

 

[buzzlightyear]

The electrician has ran 2 25mm 3core armours to another 2 DB’s in the mansion, and there has to be a DB fitted where the incoming supply is, bringing it to a total of 3 DBs.

Pic would be nice, and a diagram.

 

[Nelly72]

Pic would be nice, and a diagram.

Trying to attach a quick diagram sketch I just done. It says the file is too big

 

[DPG]

Trying to attach a quick diagram sketch I just done. It says the file is too big

Screenshot it and send the screenshot. Crop it if required.