100amp Isolator switch required

[Building advice]

Hello everyone. I'm hoping you can advise. I am in need of a 100amp fused isolator switch with a tiny footprint. Any recommendations please? Thanks

 

[Wilko]

Hi BA and welcome to the Forum .
Can you tell us a bit more? What's it for and why must it be small?

 

[Pete999]

Hello everyone. I'm hoping you can advise. I am in need of a 100amp fused isolator switch with a tiny footprint. Any recommendations please? Thanks

Have a look at the various items in the relevant electrical catalogues.

 

[telectrix]

wylex or click do a KMF but only to 80A.

 

[westward10]

Single pole or triple pole.

 

[telectrix]

or even double pole

 

[Charlie_]

Or even 4 pole

 

[ruston]

Or @SWD

 

[buzzlightyear]

Or even 5 poles dancing

swd in the middle.LOL.

 

[Charlie_]

Tel you are gonna need another freezer!

 

[Building advice]

Thanks for all the replies. I have relocated my CU. It was originally next to the mains meter and is now much further. I believe I will need the isolator switch next to the meter now. I didn't realise I would need this as the whole point of moving it was so that it was less noticeable. But now I've been told I will need the switch next to the meter so I'm trying to get it as small as possible. Thanks

 

[Squid]

swd in the middle.LOL.

See, I bring out the best in you at least the spelling is correct for a change, just need to teach you how to use capital letters and to write your own name. ;o)))))

 

[westward10]

Thanks for all the replies. I have relocated my CU. It was originally next to the mains meter and is now much further. I believe I will need the isolator switch next to the meter now. I didn't realise I would need this as the whole point of moving it was so that it was less noticeable. But now I've been told I will need the switch next to the meter so I'm trying to get it as small as possible. Thanks

Assuming you are using swa you won't get much smaller than this. Lewden is generally a poor quality option but it is what it is.
Lewden 100AMP SP&N SINGLE POLE AND NEUTRAL FUSED ISOLATOR SWITCH - https://www.superlecdirect.com/p-fs6380100-lewden-100amp-spandn-single-pole-and-neutral-fused-isolator-switch?gclid=CjwKCAjwtYXmBRAOEiwAYsyl3PyBWmBRg3gV7K5M4dUBPWPgWVF1weX3cCHt2BslHNr4M8uADjQCbBoCFAMQAvD_BwE

 

[Building advice]

I was intending on using 25mm2 double insulated cables

 

[buzzlightyear]

See, I bring out the best in you at least the spelling is correct for a change, just need to teach you how to use capital letters and to write your own name

LOL.

 

[Squid]

I always thought it was "Cockwomble"

 

[davesparks]

I was intending on using 25mm2 double insulated cables

Are you able to install them in such a way that they won't need RCD protection? And where are you getting double insulated cables from?

 

[davesparks]

Thanks for all the replies. I have relocated my CU. It was originally next to the mains meter and is now much further. I believe I will need the isolator switch next to the meter now. I didn't realise I would need this as the whole point of moving it was so that it was less noticeable. But now I've been told I will need the switch next to the meter so I'm trying to get it as small as possible. Thanks

How on earth did you carry out the cable calculations for the submain without an OCPD rating for the circuit?

 

[Building advice]

Thanks for replying. I am not an electrician. I am acting on advice given to me by a friend (who is a sparky) and the electric wholesaler I have been purchasing materials from. So sorry but I have no idea about your question davesparks.

 

[westward10]

Best let your electrician make the choice and not make decisions from hearsay.

 

[Toneyz]

Your sparky mate needs to give you an exact list of materials from his design.

 

[Charlie_]

From what I have experienced, Wholesalers shouldn’t really be giving advice out..

 

[PEG]

I always thought it was "Cockwomble"

I can remember madame cholais,uncle bulgaria and tobermory....
I'm certain THAT one would have stuck in my mind...

 

[Building advice]

Hi guys. I need your help as I'm more confused than ever having spoken with another Electrician. He told me I cannot move the incoming supply over 3m unless it was armoured 25mm2 cable. Having the fused isolator switch and then running in 25mm2 non armoured cables apparently isn't allowed?? I've had a look at the 25mm2 armoured cable and it is not going to be a easy cable to manipulate. Help!

 

[DT1991]

Can you not employ either of these electricians to just install and certify?

And to the other electrician that advised you that proberly is his generic design he does of the top of his head for a simple domestic installation.

 

[Lewis Ashton]

You would need to look at RCD protection if not using the armoured cable. That housed in an enclosure, along with the 100A switched fuse unit, and you're probably at a similar sized setup to having just placed your consumer unit there.

 

[Building advice]

The problem is the builder who has undertaken all the wiring work is expecting to turn up tomorrow and install the cable (which I should have purchased by now). He is not a qualified electrician and instead gets his work certified at the end. I thought I had the solution for him i.e. the isolator switch and the double insulated cables and these were the things I went to purchase. Unfortunately the electrician in the shop explained to me that I could not do this. He quoted some regs. 434.1.2 ??? Can you really not move the incoming supply using a fused IsolatIs switch and running in double insulated cables??

 

[Deleted member 105166]

The shortened version...

The problem is the builder

 

[DT1991]

The double insulated tails would need installing in such a way that doesn't require RCD protection.

 

[Building advice]

DT1991 can this be done if they are 15m long??

 

[Building advice]

By the time they've gone up walls and through ceilings they will be this long

 

[Charlie_]

What did building control say when you notified them prior to any work starting?

 

[DT1991]

RCDs: protection of cables concealed in walls or partitions - https://electrical.------.org/wiring-matters/issues/54/rcds-protection-of-cables-concealed-in-walls-or-partitions/

 

[Deleted member 105166]

He is not a qualified electrician and instead gets his work certified at the end.

What happens if he gets things badly wrong and injures/kills himself or someone else, or a fire results in the meantime? Whose insurance policy covers the liability? Is your home insurance still valid if you employ a non-electrician to carry out a CU replacement/move, which is notifiable to building control? What/when is "the end" in this context?

 

[Building advice]

Thanks for all your help. I will have to or everything on hold until I can get an electrician to do the move. All the new wiring has already been moved to the new CU spot. If it hadn't I would have sicks to the original location of the CU. More hassle than its worth!

 

[Building advice]

I just hope that it can be done and does not require any digging!

 

[baldelectrician]

MCB for circuit protection - C120 | Schneider Electric UK - https://www.schneider-electric.co.uk/en/product-range/61088-c120/?N=546130139+1920620548+733925695&_requestid=282307#tabs

 

[Building advice]

Thankyou for that baldelectrician. It looks a lot smaller. Where can these be purchased from? That site doesn't have prices? Thanks

 

[baldelectrician]

Thankyou for that baldelectrician. It looks a lot smaller. Where can these be purchased from? That site doesn't have prices? Thanks

Ask your electrician to order through the wholesaler, be expected to get little change from £100

 

[Building advice]

Ok thanks

 

[Deleted member 26818]

If the cables to the new CU position are to be concealed in any walls, then it’s very likely they will need RCD protection.
If however they are just going to run up the surface of the wall into the ceiling and along to drop down into the new CU, RCD protection will not be needed.

 

[Building advice]

Thanks for that. The builder and I have managed to get the cable in today. It's a 25mm swa cable and it goes behind a stud wall and then up into the ceiling and then back down into the room where the CU is situated. In this case will the miniature circuit breaker not suffice? Thanks

 

[Deleted member 105166]

Thanks for that. The builder and I have managed to get the cable in today. It's a 25mm swa cable and it goes behind a stud wall and then up into the ceiling and then back down into the room where the CU is situated. In this case will the miniature circuit breaker not suffice? Thanks

How is your electrician going to inspect this cable? From what you have described, much of it is concealed. It would have been a better idea to assist your electrician in pulling it through, rather than the builder.

 

[Building advice]

I've taken photos and it was cheaper to get the builder to sort this side. The electrician will come later to hook up one side to the meter and the other to the CU.

 

[Charlie_]

Sounds like mcb will be ok, saves on the enclosure but the electrician will make that decision when he connects it all up

 

[Deleted member 26818]

Armoured cable doesn’t need RCD protection.

 

[DPG]

All this time and hassle to save money on just getting an electrician in to design/install/test the job properly.

 

[davesparks]

Thanks for that. The builder and I have managed to get the cable in today. It's a 25mm swa cable and it goes behind a stud wall and then up into the ceiling and then back down into the room where the CU is situated. In this case will the miniature circuit breaker not suffice? Thanks

Hopefully you've left plenty of working room for the electrician to work on the cable an dfit the correct glands to the end of it. You can't just leave an SWA that size sticking out of a stud wall and expect someone to be able to terminate it into the back of an enclosure.