Fitting consumer unit vertically

[JohnW2]

Now, if someone were to produce a 100a DP din rail mounting connector block designed to replace the isolator in the CU and link the tails to the busbar and neutral block, that might be a nice solution. I guess each manufacturer would have to do their own and type test it in their own CU - demand would probably not be great enough for them to do that.

Maybe, but it wouldn't really be necessary. No-one (and no regulation) is saying that the 'single point of isolation ' for the installation cannot be duplicated - so the main switch could remain, with the separate external upstream isolator wired to it, just as is the case with millions of domestic installations which have had an 'isolator' installed upstream of the CU (to facilitate work on the CU, or whatever).

... and I don't see any safety downside to that. In an emergency/panic, it wouldn't matter which of the two 'isolators' the householder chose to operate ... or am I missing something?

However, as I've said, I don't think that a 'horizontal' Main Switch is really a problem/issue, anyway.

Kind Regards, John

 

[JohnW2]

Install the CU upside down!

The point is that they seem to cope quite happily with it installed the right way up.

Kind Regards, John

 

[davelx]

Maybe, but it wouldn't really be necessary. No-one (and no regulation) is saying that the 'single point of isolation ' for the installation cannot be duplicated - so the main switch could remain, with the separate external upstream isolator wired to it, just as is the case with millions of domestic installations which have had an 'isolator' installed upstream of the CU (to facilitate work on the CU, or whatever).

... and I don't see any safety downside to that. In an emergency/panic, it wouldn't matter which of the two 'isolators' the householder chose to use. ... or am I missing something?

Kind Regards, John

No, you're not missing anything. Some here say that having two DP isolators in line is just one more thing to go wrong, one more set of connections to work loose. So maybe nice, but certainly not necessary.

 

[JohnW2]

No, you're not missing anything. Some here say that having two DP isolators in line is just one more thing to go wrong, one more set of connections to work loose ...

They do, and their argument is theoretically correct but it doesn't alter the fact that millions of domestic installations (and probably others), including mine, have just that.

I very much doubt that isolators (only rarely operated) hardly ever 'go wrong' as such - and, in terms of the additional number of connections to work loose, if my counting is correct, your postulated solution would not involve any less such connections, would it?

Kind Regards, John

 

[securespark]

I have a CU with an RCD incomer. And a separate isolator.

And they're both made out of HIGHLY FLAMMABLE plastic.

And I'm still alive.

Yee-haw! It's like dodging The Grim Reaper!

 

[pilsbury]

Thanks for the replies - seems I may be able to go vertical. Space is 250mm

 

[Taylortwocities]

Thanks for the replies - seems I may be able to go vertical. Space is 250mm

And how many ways (MCBs and RCDs) do you need??

 

[sparkwright]

What about two small consumer units, one above the other?

 

[John D v2.0]

To be honest I think the main isolator should be outside the cu on its own, then it's clear that it's the main switch and no confusion whether anything else is the main switch.

 

[JohnW2]

To be honest I think the main isolator should be outside the cu on its own, then it's clear that it's the main switch and no confusion whether anything else is the main switch.

Is that a general statement? If so, are you suggesting that CU's should not have 'Main Switches'? Since I very much doubt that that is the case, perhaps you could clarify your point?

As I said before, if (like me and millions of others) one has a standalone isolator upstream of a CU (with a Main Switch) there is not really any safety issue related to confusion - since, in an emergency/panic, it virtually never matters which one is operated (and if there are flames coming out of the CU, most people would probably favour using the standalone one ).

Kind Regards, John

 

[John D v2.0]

Yes I'm basically saying a standalone one should be the main switch and labelled as such. Then less chance of someone operating an rcd or mcb thinking is a main switch.

 

[JohnW2]

What about two small consumer units, one above the other?

Indeed - but that approach presumably does theoretically require a separate external isolator ("single point of isolation") and, I would have thought, probably some sort of warning labels to indicate that the Main Switches (assuming they exist) in the CUs do not, individually, isolate the entire installation?

Kind Regards, John

 

[JohnW2]

Yes I'm basically saying a standalone one should be the main switch and labelled as such. Then less chance of someone operating an rcd or mcb thinking is a main switch.

Hmm - so this is just something hypothetical on your 'wish list'? As was mentioned earlier, a CU without a main switch is only feasible if one has some way of connecting the incoming tails.

Kind Regards, John

 

[EFLImpudence]

If you have an external main switch, then you can get eight RCBOs in one of these - or have two.

http://www.discount-electrical.co.u...r-unit-with-switch-disconnector-isolator-100a

or have two.

 

[JohnW2]

If you have an external main switch, then you can get eight RCBOs in one of these - or have two.

Yes - but, as I've just written, if one does away with the main switch (and uses that space for RCBOs), then how does one connect the incoming L to the L-busbar (the incoming N can go to the neutral bar).

Kind Regards, John