Wifi mesh extender on lighting circuit?

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Is there a regs compliant way to power a wifi mesh unit from the lighting circuit? The devices have a plug in adapter so it would involve a socket rather than wiring it in like a bathroom extractor, does that make it break the rules?
 
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Nothing to prevent you supplying a 13 amp type socket from a lighting circuit.

Best to label it as "WiFi Unit Only" to reduce the risk of someone using it for a vacuum cleaner which would likely trip the MCB for the lights
 
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There is no reason I can think of, why a 13amp socket could not be powered by the lighting circuit, providing it is protected by the usual 6amp MCB at the consumer unit and not fitted in a bathroom. Obviously mark the socket as 'not for general use'.

I needed a socket to power a DECT phone charger, where it would have been difficult and disruptive to wire a socket onto my upstairs ring circuit. Where I needed the socket, was an isolator and PSU for a stair lift, fed from a 6amp MCB. I simply added a 13amp socket adjacent to that, powered from the 6amp supply and marked 'PHONE CHARGE ONLY'.
 
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Thanks both. The connections would ideally be hidden in the ceiling space so no danger of inadvertent usage. But I need to check for heat dissipation.
 
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I guess an alternative is to source a transformer of the right output that can be hard wired.
 
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Ignore Winston's opinion.

The connections would ideally be hidden in the ceiling space

The socket needs to be accessible and not concealed,. Especially as it will have a power supply module plugged into it.

These "plug top" power supplies are often designed to operate and dissipate heat into free air as when plugged into a normal wall socket.

In a confined space without air flow the power supply module may over heat and fail. Worse case would be a fire.
 
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The only problem using the wifi adaptors is same if lighting or power, the RCD must be suitable, I think for high frequancy it needs to be type F?

I was unaware my Sky Q boxes used the technology, and since I can't get type F RCBO's for my consumer unit, in theroy I should turn it off. However I am just taking a chance, I have ordered type A to replace the type AC but I feel the risk is low.

Your idea of using lights is likely lower risk to using sockets as there is less likelihood of needing RCD protection, if of course the lights and power are not on the same RCD.

Note a RCBO is a RCD and MCB combined, so in my case with all RCBO's it should only affect the circuit it Is connected to, but my Sky Q boxes are connected to two ring finals, so swapping both those RCBO's I don't think the high frequancy stops the RCD working but it may delay it?
 
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The only problem using the wifi adaptors is same if lighting or power, the RCD must be suitable, I think for high frequancy it needs to be type F?
I can't see that there is anything particularly unique about WiFi adaptors.

Am I the only person who feels that many of these recent discussions about types of RCD are a bit OTT? In any event, I would imagine that it's very likley that the PSU of this device will be Class II, in which case RCD protection of it would be of very limited value, if any.

Kind Regards, John
 
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Am I the only person who feels that many of these recent discussions about types of RCD are a bit OTT?

No you are not.......

I would imagine that it's very likley that the PSU of this device will be Class II

Quite probably, no Earth connection. just Live and Neutral so no route for the earth leakage current necessary to trip an RCD

in which case RCD protection of it would be of very limited value, if any.

RCD protection would only be any use if the PSU went into meltdown, destroyed or bypassed it's internal isolation and thus connected it's SELV output to the incoming mains. If that happened then the previously SELV wiring would need RCD protection.
 
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No you are not.......
I'm glad that I'm not alone. To be fair, it's really only one person who keeps raising this 'RCD type' issue.
Quite probably, no Earth connection. just Live and Neutral so no route for the earth leakage current necessary to trip an RCD
Exactly.
... RCD protection would only be any use if the PSU went into meltdown, destroyed or bypassed it's internal isolation and thus connected it's SELV output to the incoming mains. If that happened then the previously SELV wiring would need RCD protection.
Even then, certainly in the OP's case, I don't think that the RCD protection would be particularly useful. With no local connection to earth, there would be no opportunity for a leakage to earth to arise within the SELV circuitry and, since we're talking about something which would very rarely be touched (and, it sounds, quite possibly not even accessible) at any time (let alone when 'in meltdown') by someone whose body provided a path to earth - not to mention the fact that all of the SELV circuitry would probably be within an insulated enclosure and hence not even 'touchable'.

Kind Regards, John
 
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No you are not.......



Quite probably, no Earth connection. just Live and Neutral so no route for the earth leakage current necessary to trip an RCD



RCD protection would only be any use if the PSU went into meltdown, destroyed or bypassed it's internal isolation and thus connected it's SELV output to the incoming mains. If that happened then the previously SELV wiring would need RCD protection.

I think the suggested problem is that the power supply will take a DC component from the mains which could affect the RCD which is protecting other things.
 
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I think the suggested problem is that the power supply will take a DC component from the mains which could affect the RCD which is protecting other things.
Eric's concern appeared to be about 'high frequency' components, rather than DC components.

However, regardless of what component of the current one is concerned about, the total current (hence any component thereof) drawn during normal operation by these tiny SMPSUs is so small that I sincerely hope that no component of it is anything like enough to impair the satisfactory functioning of an RCD. There are countless millions of these things in service all the time (often several simultaneously protected by the same RCD), and if it were believed that this could significantly impair RCD function, the use of type AC ones would surely be 'banned', at least on sockets circuits?
 
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