Joining CU neutral terminal blocks

Jan 18, 2019 Last reply: 7 years ago 19 Replies

I have a MK Sentry split load CU that I am turning into an all-RCBO board, so I need to join the neutral bars together. The existing board had 4 neutral sections with the first two joined together by a rather thin-looking U shaped link. The neutral bars are supposed to be able to take 16mm cable. Can I just join them together with 16mm rigid cable like the stuff you use for large earth connections (obviously will be sleeved in brown) ? Thanks, Simon.


"obvs" I mean blue ! Must be time for the weekend.

Yes, although to comply with type approval it should really be a genuine MK part.

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If you do make your own, some will say it should have crimped ferrules.

Owain

LWT used to start transmitting at 7.00pm on Friday evening. That always marked the start of the weekend for me.

I don't think that cable will fit in the neutral terminal block, it is for joining switches and only fits in the top of the switch which has much wider "holes".

Surely crimped ferules is only for fine strand cable ? The point about using the 16mm singles cable is that being made of a few thick "wires" it does not need a ferrule.

Simon.

The factory made split load 16mm tri-rated cables have on one end a rectangular ferrule about 2mm x 8mm, and on the other end something like in the following link, although this does not look like a crimp, more like a solder item.

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Ah, this says they are crimps:

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magic phrase is 16MM UN-INSULATED REDUCING PIN CRIMP.

But when crimp the shape seems to turn into an indented hexagon, so that is a heavy duty crimping tool. I could find a local electrical firm that could modify my spare split load cables by putting one of those on the other end.

I'm not sure about reducing the conductor size so much, but that seems to be the way it is done. I suppose its only a few millimetres at the reduced size.

Simon.

Back in the old 405line days it was always fun early on a weekend morning to tune around the channels looking for the different pompous start up sequences of each ITV company. Now its all a bit like homogenised milk. All the same and tasteless. Brian

Use black for that pre 2004 experience.

16mm will have 7 strands. It will be fine.

OK thanks, just needed to check it would pass inspection !

Putting in more RCBOs I need to tidy the wiring up a bit. I have plenty of slack. It seems like the best practice is to run the incoming circuit cables quite low behind the RCBOs and then loop them back up to be connected. That way you avoid a rats nest crammed in above the RCBOs.

Simon.

Just a thought. Its nice to have light in the CU cupboard ! What is the simplest acceptable way to wire (surface-wired) a light so it can be on when the CU main switch is off ? Perhaps without fitting a whole second mini-CU, henley blocks, etc. e.g. via a fused switch directly from the main incomers.

Simon.

I suppose if you've got the live bus bar out you could just run a wire to energize the light in cupboard circuit, but the main switch would have to be on.

Simplest is a battery backed up emergency lighting unit from a lighting MCB.

You can't do a FCU from the main incomers as a BS1362 plug fuse won't have the breaking capacity (6 kA).

BS1361 type I are 16.5 kA (HBC cartridge fuses for consumer units) and BS1361 type II (supplier cutouts) are 33 kA.

Owain

Non-maintained emergency light fed from a circuit on the CU, if mains fails or you turn that MCB off, the light comes on ...

sm_jamieson formulated the question :

There is no other way I can think of. Unless you think in terms of an emergency light, or some sort of battery powered light.

Thanks all, yes an emergency light is the best idea of course, and if the power is lost competely it comes on (to state the obvious).

Use a good head-mounted LED llight

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just aim it upwards and it lights up most things.

Still time before it starts ;-)

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