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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> Add MCB https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1095934108 Message started by Hobo on Sep 23^rd, 2004, 11:08am

Title: Add MCB
Post by Hobo on Sep 23^rd, 2004, 11:08am

We are just getting a stair lift fitted,(for Mum),
I would like to add a seperate MCB to the existing Crabtree Starbreaker.To isolate the lift from the existing ring main. The consumer unit is next to where the socket would need to be, do I have to leave a min. dist between them? I have only used Merlin Gerin units in the past, after Isolating do I just unscrew and fold out, then clip the new MCB inplace? Sorry, 2 questions, but just found your fine site, good for out of date people like myself!

Title: Re: Add MCB
Post by The_Trician on Sep 23^rd, 2004, 11:36am

Sounds ok to me. There isn't a regulatory value given for ther distance between a 13A socket and a Cu as far as I know.

Stair-lift supplies are usually wired like this -

13A socket to 13A plug.
13A plug to remote RCD unit.
RCD unit to stairlift wall-mounted controller.

Hope this helps.

On Stannah lifts, there's alos the chair-mounted up/down but this bit is already incorporated into the chair and shouldn't concern you.

TT

Title: Re: Add MCB
Post by plugwash on Sep 23^rd, 2004, 12:08pm

if running an individual socket from the CU best to use a 16A breaker

also this really should be on the non-rcd side don't wan't the user stuck upstairs because their faulty appliance took out the rcd

Title: Re: Add MCB
Post by The_Trician on Sep 23^rd, 2004, 12:13pm

Hi Plug,

The installers insist on an RCD-protected supply because believe it or not, a stairlift is classed (to them) as a portable appliance or moving machinery where there is a risk of being trapped.

That's what the Stannah engineer told me when they did one for my mum a few years ago.

They were concerned that the flexible 3 core to the moving chair bit, which rolls up and unrolls as the chair moves, might get trapped or damaged, so they fit an RCD by default mate.

TT

Title: Re: Add MCB
Post by L.Spark on Sep 23^rd, 2004, 1:37pm

Best not to assume with things like this what does and does need an RCD, always consult manufactorer or company responsible.

and having a socket next to the CU is ok, and a 16A breaker should be used as plug said.

Quote:

They were concerned that the flexible 3 core to the moving chair bit, which rolls up and unrolls as the chair moves, might get trapped or damaged, so they fit an RCD by default mate.

The ones ive seen usualy have what looks like a chainlink protective open trunking allmost, which Surrounds the flex.

Title: Re: Add MCB
Post by Beanzy on Sep 23^rd, 2004, 1:56pm

Nice and simple would be a spurred RCD protected Fused Connection Unit from the ring. That's what the neighbours had on their one. Need the Load though before could make that decision.

If seperate spur is best for you you can see if these ABB RCBOs fit in the starbreaker units. Your wholesaler may be able to let you have a look at one for comparison, if you bring one of the Starbreaker ones with you, and they'll almost cerainly be cheaper then CPC by the time carriag is taken into consideration, (a/c customers get free next day).

http://custom1.farnell.com/cpc/product.asp?catalog%5Fname=CPC+Catalogue&category%5Fname=Electrical%2C+Security+and+Test+%2D+Mains+Electrical+Accessories+%2D+Circuit+Protection&product%5Fid=277999

I've used them for workshop supplies and they've been very useful.

Title: Re: Add MCB
Post by Hobo on Sep 23^rd, 2004, 2:21pm

Thanks All,
Amazing help! The stairlift they are fitting is a rechargeable battery type, so I only want a seperate socket from the ring, I will fit it RCD side on a 16A. Is the clip on rail still fairly standard these days?

Title: Re: Add MCB
Post by Hobo on Sep 23^rd, 2004, 2:25pm

Sorry forgot to add, the reason for not using a spur is to save making to many new channels in the wife's re-decorated walls!

Title: Re: Add MCB
Post by plugwash on Sep 23^rd, 2004, 2:29pm

fine rcd protection may be needed

but it should be a seperate RCD it should *NOT* be on the same rcd as the rest of the house

would you wan't a member of your family stuck upstairs with the main house rcd off and no way to get out or get help?

Title: Re: Add MCB
Post by L.Spark on Sep 23^rd, 2004, 3:33pm

no certainly it should be seperate from the common RCD in the board, Should be a RCD Protected Fused Connection Unit or a RCD Protected Socket Outlet, either of them supplied from the NON Protected side of the board.

You don't need to chase out the walls if you don't want too Hobo, Use some surface trunking or simliar if it's a short distance from the board it won't look too bad

Remember to isolate the board when you decide to fit this up.

Title: Re: Add MCB
Post by The_Trician on Sep 23^rd, 2004, 7:57pm

When they did my mum's they fitted 16x25 mini-trunking and a stand-alone surface-mount RCD unit - not an FCU, just a unit with L+N+E in and L+N+E out for the flex supply.

This was done by an NIC-approved contractor via Social Services.

TT

Title: Re: Add MCB
Post by supersparky on Sep 23^rd, 2004, 8:01pm

something like this may be sutable?
http://homepage.ntlworld.com/john.kane10/stairlift.gif

(thanks HM)

ss

Title: Re: Add MCB
Post by The_Trician on Sep 23^rd, 2004, 8:08pm

Its a belter ss! I wonder if Thora Hird has one of those...?

TT

Title: Re: Add MCB
Post by L.Spark on Sep 23^rd, 2004, 9:14pm

haha, now come on, this is meant to be a serious post!! ::)