Shower cieling switch / cable crimping

[Bob]

The pull cord switch for the shower stopped working last night and on opening up I discovered that the live terminal had burnt and the switch damaged. I understand that the likely reason for this is that the connection might have been a bit loose leading to higher resistance etc.

Anyway I am about to go up into the loft to see if there is any slack in the cable. Otherwise I think I am going to have to crimp a section in. I don't have any heat shrink sleeving at the moment and, looking online, the only place I can see that is open and I can get to only has up to 13mm sleeving. I don't think this will be big enough for 6mm cable. Or might it be? Are there any alternatives to heat shrink sleeve that might be more available?

Thanks,

Bob

[Mike Clarke]

Junction box?

[A.Lee]

Get a foot long length of cable, a properly rated junction box, then pull through the old cable, in the loft, attach to new cable via junction box in loft, and you have enough slack to play with. Alan.

[Mike Tomlinson]

In article , Bob writes

I don't think I would crimp and sleeve 6mm cable that could be carrying

45A or so. Suggest you use a proper junction box rated for the cable, mounted in the loft, fixed to a joist, and run a new length from that down to the shower switch.

[Bob]

To be honest, that sounds more straightforward but, looking around, the consensus seems to be to crimp as a junction box is yet another connection that could potentially fail. Or are you saying to do that as a temporary measure until I can get hold of the proper crimping stuff?

It is a bit moot now as I've been up in the loft and there is already enough slack to play with. I'm still interested though as I'd like to prepare myself for if it happens again.

Bob

[ARWadsworth]

You will not go wrong with a 60A juntion box

terminals than your shower pull switch, MCB and neutral busbar!

[dennis]

It is common practice to crimp high current connectors. Crimps are far better at carrying current than screw connectors and are far more reliable. Crimps are used on stuff carrying hundreds of amps.

[js.b1]

Nothing wrong with crimping subject to 1) correct quality crimp tool which is =A320 AND 2) decent Tyco/Amphenol/PIDG crimps which are not so expensive.

Therein is the problem, most people do not have decent quality crimps

- and that is just to 6mm (Yellow).

If you have 10mm cable then you need a copper tube crimp which is about =A325 from Screwfix with butt-splice tubes, and adhesive heatshrink, and an enclosure. Many crimp tools are not that good as you go past 16mm, because of the forces involved and a lot of knock- off rubbish.

A proper crimp is a cold-weld and is actually quite demanding on crimp tool, crimp & even particular conductor makeup. A bad crimp is a fire at battery-terminal voltage/current, never mind shower voltage x current x duration.

So go with the proper TLC 60A junction box. You want want to write on the inside of the shower casing with permanent marker "60A J-B in ceiling void above" if you forget etc.

[Mike Tomlinson]

In article , harry writes

Eggsactly. dennis vs. Real Life (tm) again.

Don'tcha love armchair critics like dennis and dribble?

[Mike Tomlinson]

In article , js.b1 writes

[snip a lot of sense]

Thank you.

[geoff]

In message , Mike Tomlinson writes

And harold, don't forget the new kid on the block

[John Rumm]

Without sleeving you could use some other form of enclosure.

In this circumstances, crimps will give a good joint, but only if you have a decent quality crimp tool and yellow insulated crimps. Alternatively the proper 60A junction boxes are also very good and have decent terminals that will let you get a good connection (far better than in the switch in all liklihood!)

[Bob]

Actually I do, but as I said, I've never used it for cable that big.

Anyway I needed neither junction box nor crimps this time.

Interesting to see that opinion is on the side of the JB here. I googled around last night having discovered the problem and found it seems to be quite a common problem. I came away with the impression that crimping was favoured.

Bob

[dennis]

Why isn't he likely to have one? He did say he preferred screw terminals to crimps which indicates he has crimps. Even if he doesn't crimps are still better than screw terminals as I said.

I have crimped 70 mm2 cable even if it was only an earth cable. It sounds like you don't have a clue.

[Bob]

Apologies - I never said any such thing. I just thought I'd said it.

And while I'm here, just in case anyone thinks I can't spell ceiling (see thread title) - I can!

Bob

[geoff]

In message , "dennis@home" writes

Dickhead - I prefer Laphroaig to Domestos

doesn't mean that I have any, does it - as would follow from your argument

[geoff]

Rule of thumb here is

If harold or dennis suggest it, be wary, be very wary

[dennis]

Shame that he has posted saying he does then. Its just evidence that you are too thick to conclude the obvious.

[dennis]

Rule of thumb here is that geof never posts anything useful.

[geoff]

In message , "dennis@home" writes

No its not dennis

the fact that he did in fact have one has no bearing on the fact that you jumped to the conclusion