12v DC power from lighting circuit in loft space

[James Allison]

Hi,

I've very little experience with wiring (other than a 18 yr old physics A-level), so was looking for a few pointers.

I have a 4G LTE router I'd like to run in our loft, as it has far better reception up there - but alas, there are no plug sockets.

The lighting circuit is accessible - but from what I understand, any general socket fitted needs to be backed by an RCD, so this would also need to be fitted. I also understand that lighting circuits aren't supposed to go above 6A, so a 13A socket would be frowned upon. (I've read it's permitted, but must be clearly labelled - in any case, it seems sketchy and likely to be misused at some point).

The router itself runs on 12V DC, from a 2A transformer. Would an LED driver (or similar), wired into a switch off the lighting circuit be something that could be certified (and not burn my house down) to run this? Has anyone done anything similar - or is this idea just silliness?

Cheers

 

[Spoon]

Welcome to the forum mate.
Is the transformer part of the plug?
If you have 'very little experience with wiring' do you think you would be safe hacking into the light circuit?

 

[James Allison]

The transformer the router came with was one of those wall wart efforts - so whilst it would be fine in a socket, I wasn't proposing to use it in the loft.

I'm mainly looking to do the minimal changes to get this running, and since 12V DC LED drivers are definitely designed for lighting circuits - I was hoping to hear if anyone had any experience of using them to run alternative electronics.

I'm sure I can 'hack' at the lighting circuit safely to add a switch and driver, but am unsure if running 'things that are not lights' would block any kind of certification happening.

 

[Spoon]

I'm sure I can 'hack' at the lighting circuit safely to add a switch and driver, but am unsure if running 'things that are not lights' would block any kind of certification happening.

I did mean 'hack' in a friendly way mate.
If you require an electrical certificate for the change to the circuit then you will need an electrician, with relevant test gear, to test it for you.

 

[James Allison]

- Yeah, putting '...'s around words can sound overly hostile - sorry about that! (absolutely not intended)

Thanks for the advice. From what I understand I don't need a certificate to replace a fitting (so to replace the bulb with the driver on an existing switch is fine) - but to add a new switch would require an electrician over.

My main question is if anyone has successfully used one of these (or similar):
https://www.amazon.co.uk/1-Pack-Premium-Voltage-Transformer-Switching/dp/B01N1UPGHN/

to power one of these (or similar):
https://www.amazon.co.uk/Huawei-Unlocked-Mobile-Wi-Fi-Router/dp/B073VBYFL5

from the lighting circuit.

 

[Ned Gibbons]

Are you planning to run any cat5 to the router. If so then look at a power over Ethernet solution.

 

[Shoei]

Best to avoid lighting inverters to supply regular electronics, they're optimised for lighting loads, typically have high levels of electrical noise on the output and may not regulate voltage well at low current.

There's a thread here on a similar situation, the view there seems to be it's ok to add a 13A socket to the lighting circuit so long as it's clearly labelled and certified. That would allow you to use the manufacturer's supply which would be good for the warranty.

You could consider 12V supplies designed for security cameras. They're typically 12V, and larger ones have a mains input cable which could tap into the lighting circuit, with the same provisos as above.

 

[Zdb]

On the rare occasion that I've tapped into a lighting circuit to supply low power electronics via a socket outlet I have installed the socket outlet inside an enclosure and labelled it appropriately.

Having it inside an enclosure makes it far less obvious and therefore should stop someone from unplugging your kit and plugging (overloading) other things into it.

Not ideal I know but sometimes necessary.

The main scenario where I have had to do this by the way is for fibre optic lighting into a ceiling for a star effect. It came with a transformer built into the plug so left me with little option and as it was lighting after all I saw no real issue.

Hope this helps

 

[Zdb]

For your reference

 

[telectrix]

might need a bigger box if the PSU is integral with the plug.

 

[James Allison]

Best to avoid lighting inverters to supply regular electronics, they're optimised for lighting loads, typically have high levels of electrical noise on the output and may not regulate voltage well at low current.

Thanks - this is exactly what I wanted to know. I'll not do this then!

Are you planning to run any cat5 to the router. If so then look at a power over Ethernet solution.

I'd overlooked PoE as the router I have didn't have it - however, a splitter only costs £8 - and solves that problem very nicely.

In the more general case, it seems the concensus is that a well marked socket off the lighting main is a much more sensible option than a hard wired transformer.

Thanks everyone for the advice!

 

[littlespark]

The lighting circuit is accessible - but from what I understand, any general socket fitted needs to be backed by an RCD, so this would also need to be fitted...

Since the 18th edition of the regs came out, lighting circuits need to be covered by an RCD as well as sockets if the circuit is altered.

.It is fine to add a socket to a lighting circuit, if labelled and, in an attic, no ones going to be plugging in a kettle or vacuum cleaner.