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dogman

Main disconnect switch

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I am looking to get a disconnect switch fitted between the meter and the henley block as i will be having two metal enclosures and it means i can get the meter moved first 

 

Whilst looking at options i saw a picture of an installation where the switch was an RCD with rcbos in each enclosure.

 

As i am looking at either an all RCBO installation is the use of an RCBO as the disconnect a good idea. My electrician is not the best at answering questions so its probably quicker on here.

I remember a debate on here about the neutral not being disconnected by RCBOs so is the RCD an answer to that problem? 

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If the board is all rcbo then you do not want an up front rcd, unless you are on a TT earth where you will be forced to, in which case you have a time delay RCD to provide discrimination.

 

I assume this is just temporary as you are having the meter moved first?  If that is the case, I would do nothing right now. Book the meter move. Make sure your electrician is on hand and you have a double pole 100A switch and a REC2 enclosure for it. When the meter monkey moves the meter, get him to connect the meter to the input of the isolator switch, and then your electrician connects the output of the switch to your consumer units.

 

If your consumer units will be remote from the meter, then use a switch fuse instead of an isolator, such as a KMF type.

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I've got similar - a fused switch at the meter and then a double pole disconnect at the house before the CU. 

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Thanks @Prodave

 

So one of these https://www.tlc-direct.co.uk/Products/WYREC2S.html

 

The current meter is in an external box right next to the new box in the wall 

The tails will be about a meter long as the CU's are on the inside wall 

 

add. we are on TT now but should be changed to TN-C-S as main incomer is already TN-C-S but the old house was never swapped over so earth link was never made

Edited by dogman

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5 minutes ago, dogman said:

Thanks @Prodave

 

So one of these https://www.tlc-direct.co.uk/Products/WYREC2S.html

 

The current meter is in an external box right next to the new box in the wall 

The tails will be about a meter long as the CU's are on the inside wall 

 

add. we are on TT now but should be changed to TN-C-S as main incomer is already TN-C-S but the old house was never swapped over so earth link was never made

 

Thats what I have fitted at the CU end. 

 

At the meter end it's one of these :

 

https://www.tlc-direct.co.uk/Products/CGMSF100.html

 

This protects the SWA run from the meter to the house. 

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I think i better wait for my electrician to get back to me on this one as there is the added complication of a generator changeover switch in the mix that i had forgotten about.

On our cottage it we have the changeover switch in the meter box instead of the normal 100amp switch. 

 

We are on the end of the line for the supply so loose power several times a year and have a large generator to keep everything going

 

I don't want the change over in the meter box.

 

 

 

 

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If your tails just go 1 metre through the wall and out the other side then the REC2 will be fine and use the PME earth they have supplied. Put the gernny changeover switch inside next to the CU.

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Just to clarify I have 27m between the meter disconnect and the CU..!

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As an aside, one thing I REALLY regret is not having split our house wiring into essential and non-essential circuits, with separate feeds for each.  I would then have fitted a changeover switch on the essential circuit to allow either a generator or battery bank and inverter to provide power in a power cut.  It would have been easy to do when running the first fix electrics, but a real pain to do now.

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Yes split CU's does indeed seem a good idea. E

1 hour ago, PeterW said:

 

Thats what I have fitted at the CU end. 

 

At the meter end it's one of these :

 

https://www.tlc-direct.co.uk/Products/CGMSF100.html

 

This protects the SWA run from the meter to the house. 

That's what's known as a KMF switch fuse. If there is more than 3 metres between the meter and the CU then you will need a fuse of your own. you are only allowed to rely on the suppliers fuse to protect a run no more than 3 metres long.

 

I have the same switch fuse for my 25 metre run.

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I've got a stacked CU with 2 trays of RCBOs. Did consider two separate CUs but in the end it was just a cost thing. 

 

Or it will be when the sparky actually gets started on Monday.. 

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I've got a fused switch at the meter (located on an outside wall). Then SWA from there into the house.

Power went live in the house yesterday! Solar connected too.

Just the small matter now of connecting up 20 odd radial circuits and 30 odd lighting loads into the FIVE consumer units :/

 

20170926_093540379_iOS.thumb.jpg.c63f9840ba79892691684c47e47055aa.jpg

 

 

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I provided a Switch as illustrated for my rewiring of the Little Brown Bungalow, but the electrician has used a different solution involving some sort of thing that looks like a small CU.


Will have to take a piccie today.

 

@Barney12

 

Er ....

Edited by Ferdinand

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12 hours ago, Barney12 said:

I've got a fused switch at the meter (located on an outside wall). Then SWA from there into the house.

Power went live in the house yesterday! Solar connected too.

Just the small matter now of connecting up 20 odd radial circuits and 30 odd lighting loads into the FIVE consumer units :/

 

20170926_093540379_iOS.thumb.jpg.c63f9840ba79892691684c47e47055aa.jpg

 

 

You appear to have 5 double deck CU's, each probably with the capacity for a very minimum of 20 circuits, so that's 100 circuits available.

 

Talk about "room for future expansion"  I have seen industrial units with smaller distribution boards.

 

I assume there is access to the other side of that wall still otherwise how will you get the cables into them?

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36 minutes ago, ProDave said:

You appear to have 5 double deck CU's, each probably with the capacity for a very minimum of 20 circuits, so that's 100 circuits available.

 

Talk about "room for future expansion"  I have seen industrial units with smaller distribution boards.

 

I assume there is access to the other side of that wall still otherwise how will you get the cables into them?

 

Yep :D

 

CU1: 20 RCBO loads

CU2: CBUS 8 Ch Dimmer (12 DIN Ways) and 8 MCB's for each load

CU3: CBUS 12way relay (12 DIN Ways) and 12 MCB's for each load

CU4: CBUS 12way relay (12 DIN Ways) and 12 MCB's for each load

CU5: CBUS Controllers/Inputs and a bit of expansion room.

 

Here's a prebuilt unit (not what I've bought) that gives you the idea: https://www.laser.com/product_info.php/item/ART_PB_Dimmer-8ch-Pre_Built_8_channel_dimmer_L5508D1A_enclosure/cPath/168_266/products_id/1687

 

The metal CU's and RCBO's were from LiVE. The sparks were impressed with them.https://www.liveelectrical.co.uk/

They commented that the boards and RCBO's looked completely identical to Denmans own brand units.

 

Yes, the other side is a cloaks cupboard. Well that's if I don't turn it into a AV cupboard :P

 

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10 minutes ago, dogman said:

@Barney12Did you go for the SBS unit in the end?

 

No. I went direct to LiVE who put me in contact with a distro who was cheaper. SBS uses LiVE boards though.

I've gone for standard RCBO's.

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21 minutes ago, Barney12 said:

 

Yep :D

 

CU1: 20 RCBO loads

CU2: CBUS 8 Ch Dimmer (12 DIN Ways) and 8 MCB's for each load

CU3: CBUS 12way relay (12 DIN Ways) and 12 MCB's for each load

CU4: CBUS 12way relay (12 DIN Ways) and 12 MCB's for each load

CU5: CBUS Controllers/Inputs and a bit of expansion room.

 

Here's a prebuilt unit (not what I've bought) that gives you the idea: https://www.laser.com/product_info.php/item/ART_PB_Dimmer-8ch-Pre_Built_8_channel_dimmer_L5508D1A_enclosure/cPath/168_266/products_id/1687

 

The metal CU's and RCBO's were from LiVE. The sparks were impressed with them.https://www.liveelectrical.co.uk/

They commented that the boards and RCBO's looked completely identical to Denmans own brand units.

 

Yes, the other side is a cloaks cupboard. Well that's if I don't turn it into a AV cupboard :P

 

That would blow my usual "1 hour per point" estimate right out of the water.

 

Has your electrician tried SBS Trade sales, he sells the Live range of stuff and does some pretty good custom stuff, but strictly trade only?

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5 minutes ago, ProDave said:

That would blow my usual "1 hour per point" estimate right out of the water.

 

Has your electrician tried SBS Trade sales, he sells the Live range of stuff and does some pretty good custom stuff, but strictly trade only?

 

Thats why I went to a different distro who was happy to supply me.

My sparky is labour only. He's also happy for me to do all the first fix grunt. I've known him for a good while and he trusts my workmanship.

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