Three phase TT install with distribution circuit and RCBOs

[Leesparkykent]

I have an Install where a 16mm 4core has been installed previously. ATM the SWA is coiled up either end At the supply which is a barn converted in to an office for the homeowners business and plant room in new extension to the house. There is no PME available as over head, in the middle of no where and in an earlier life was a farm. My intention is to install a 100mA time delayed RCD at the supply in the office mains room and then a fused switch/switch fuse for the distribution circuit. In the plant room at the end the distribution circuit I want to install a 3 phase DB but this is where it gets a little tricky........All the circuits that need additional protection my means of a 30mA RCD will have to be put on RCBOs however I'm struggling to find single pole switched neutral RCBOs. In a single phase installation I would use SBS compact RCBOs as they are single pole switched neutral but SBS don't do three phase DBs etc. Is any one aware of a brand where I could achieve this or think of another idea?

 

[westward10]

This is a proper grey area and I don't think you will get the rcbos you need. I have used single pole on tt before with a 4 pole time delayed up front device the only problem is nuisance tripping from one of the circuits because the neutral is not disconnected. Years ago fuses and mcbs were acceptable on tt systems providing fault protection was maintained and they were single pole. Provided they are not used for isolation I don't see a problem.

 

[Leesparkykent]

This is a proper grey area and I don't think you will get the rcbos you need. I have used single pole on tt before with a 4 pole time delayed up front device the only problem is nuisance tripping from one of the circuits because the neutral is not disconnected. Years ago fuses and mcbs were acceptable on tt systems providing fault protection was maintained and they were single pole. Provided they are not used for isolation I don't see a problem.

My problems exactly that neutral earth fault on one of the circuits takes out RCBO and then the up front time delayed RCD. I cant believe I cant seem to find any single pole switched neutral rcbos for a three phase DB.

 

[westward10]

My problems exactly that neutral earth fault on one of the circuits takes out RCBO and then the up front time delayed RCD. I cant believe I cant seem to find any single pole switched neutral rcbos for a three phase DB.

Can you not substitute the triple pole board for three dual rcd boards?

 

[Deleted member 26818]

This is TT, are you sure you want to use single pole RCBOs?

 

[westward10]

This is TT, are you sure you want to use single pole RCBOs?

Don't see why not they are not used for isolation.

 

[Deleted member 26818]

What are the advantages of using single pole RCBOs?

 

[Leesparkykent]

This is TT, are you sure you want to use single pole RCBOs?

yes single pole switched neutral or double pole but I very much doubt I would find double pole rcbos in single module. Obviously the incomer kit/ main switch will be four pole.

 

[westward10]

What are the advantages of using single pole RCBOs?

Not about pros and cons the op was enquiring about double pole single module rcbos for a triple pole board.

 

[Deleted member 26818]

Well there is an Irish company called Garo which produces double pole single module RCBOs.

 

[Risteard]

Well there is an Irish company called Garo which produces double pole single module RCBOs.

They're Swedish I think, although they do have a Garo Ireland subsidiary in Dublin.

 

[Wilko]

Evening Lee - looking at this CEF page, are they any use?
10k A Single Pole B Curve Rcb Os | City Electrical Factors - http://www.cef.co.uk/catalogue/categories/rcbo-s-10ka-sp-b-curve-rcbo-s

 

[Leesparkykent]

Evening Lee - looking at this CEF page, are they any use?
10k A Single Pole B Curve Rcb Os | City Electrical Factors - http://www.cef.co.uk/catalogue/categories/rcbo-s-10ka-sp-b-curve-rcbo-s

Cheers mate, looking through the technical data they are solid neutral though.