Wall switching method for 12v adapter powered devices?

[CarbonPepper]

I'm not a pro, just looking at strategy for a village hall install.

In the bar area, there are a number of devices which need to be switched on in one go. Some LED lights, a video monitor, wifi externder, other low power stuff. They are the type with the plug in 13A to low volt wall adapters. Currently they're all in a 6 gang power strip ext lead, plugged into a 13A socket.

It's ugly and people keep changing what's plugged into the power strip, or people unplug it from the wall altogether. Some of our more elderly volunteers struggle the most.

What people want, is a flush mounted wall-light-type switch, to put all these on, and for where the adapters are plugged in to be inaccessible except for replacement, e.g. a large adaptable junction box or some such.

This isn't a proposal, just showing the concept....

DP wall switch(?) flush mounted,

To a 4x gang ext lead locked away in a wall mounted box, something like this (but with the bulky adapters plugged in). Or even some dedicated wall sockets with a box over.

Or any design alternative that can work. Very grateful for suggestions which are safe, and will help us explain the requirements to the sparky.

 

[Lucien Nunes]

Yes, that's how I would do it. The item you show is a 'fused connection unit with indicator' and is ideal. You can use it to control as many dedicated 13A wall sockets as you like. with a total maximum load of 13A. Avoid boxing the wall-wart adaptors in completely, they need some airflow for cooling.

 

[CarbonPepper]

That's very useful to know. Thanks. Spot on re the cooling.
So if we go for 3x double sockets as a dedicated, give us 6x sockets.

In terms of cable, is it going to need to cope with a potential of 6x13 = 78A? In practice I doubt it'll be any more than 2A, but I know it doesn't work that way.

Also I guess we can't add this to a ring main so we'll need to plan for the spark to quote for a new run from the CU

 

[Lucien Nunes]

It does work that way - you install to suit the design load. These socket outlets are for a specific purpose, therefore you get to state what the design load is. Had they been general-purpose outlets then one would use figures applicable to tha, which does not allow for all outlets to be fully loaded either. There's no point making it less than 13A because it won't simplify the wiring, but your two amps sounds about right.

 

[Lucien Nunes]

On which basis it's fine as a fused spur from the ring (and the load is on the ring now). The fuse in the FCU protects the spur against overload. The main reason that might justify feeding this circuit separately would be to allow the sockets to remain operational if for any reason the ring has to be isolated. But that doesn't sound particularly relevant here. If you do feed it separately, it would be conventional to create a 20A radial circuit and use a 20A DP switch. The FCU would be redundant because the MCB / RCBO in the distribution board would protect the cable.

 

[pc1966]

You can add a FCU to the existing ring final circuit, either as a new item where you want (and cable routes in walls, etc, permit), or easier immediately next to an existing socket and it is only a short cable change/route to include it in the ring.

It can be spurred off the ring, but if possible I would include it in the ring so you only have 2 wires at each terminal and not the 3 for ring in/out + spur feed. Also helps with testing in the future if it is part of the ring.

Max load is 13A, so if you want to take full advantage of it you would need 1.5mm flexible cable to your multi-way board. It seems unlikely that you would be anywhere neat it unless trying to plug in electric heaters!

 

[Soi disant]

Avoid boxing the wall-wart adaptors in completely, they need some airflow for cooling.

The problem is that as well as wanting a single point of control he wants something to deal with the problem that some of the hall users are unable to comprehend the idea of "not your sockets, not your plugs, not your devices, not your place to unplug things, leave it all alone".

 

[pc1966]

The problem is that as well as wanting a single point of control he wants something to deal with the problem that some of the hall users are unable to comprehend the idea of "not your sockets, not your plugs, not your devices, not your place to unplug things, leave it all alone".

Those pointless child-guards that plug in 13A sockets actually can be useful as you can label them "F'n not your socket!" and insert in any special power outlets to keep down the amount of basic muppetry you get.

Advanced muppetry is harder to stop, I'm afraid.

 

[CarbonPepper]

On which basis it's fine as a fused spur from the ring (and the load is on the ring now). The fuse in the FCU protects the spur against overload.

I see how that works now, thank you, that's great.

....if possible I would include it in the ring so you only have 2 wires at each terminal and not the 3 for ring in/out + spur feed. Also helps with testing in the future if it is part of the ring.

Wouldn't the wall switch then switch off the entire ring though?

 

[pc1966]

Wouldn't the wall switch then switch off the entire ring though?

No, the ring in/out to the FCU are on the supply terminals (so 2 wires per hole, as for existing sockets on the ring) while the load is connected to the separate load terminals that are fused & switched from the supply side.

 

[CarbonPepper]

Thanks for clarifying pc1966, I think I misread which bit being " spurred off" but I get it now.

Thanks guys. This is very useful. Some of the committee members need extra reassurance before asking for something they consider "unusual".

 

[Soi disant]

Those pointless child-guards that plug in 13A sockets actually can be useful

Except they should be taken off sale

as you can label them "F'n not your socket!" and insert in any special power outlets to keep down the amount of basic muppetry you get.

Doesn't help with the

[muppets] keep changing what's plugged into the power strip, or [muppets] unplug it from the wall altogether.