Electric Circuit Question

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screenman

Squire
Some of my lights do as you want, not got a clue how they are wired though.
 

midlife

Legendary Member
Presumably you leave the light switch permanently on and insert a PIR switch next to the light that turns it on. Or buy a light with PIR
 

PatrickPending

Legendary Member
Location
Leicester
personally I'd get a PIR activated lamp and put a LED bulb in it - leave it on all the time - LEDs lamps don't use a lot of electricity....in fact that's what I have done....
 

screenman

Squire
Presumably you leave the light switch permanently on and insert a PIR switch next to the light that turns it on. Or buy a light with PIR


That is not how mine work, I have a feeling there may be two power supplies to it, one switched and one not.
 

sight-pin

Veteran
I would think you would have install another switch wired from a permanent live to the pir light, or you could add a multi switch plate and run a wire from the existing switch maybe?
 

swansonj

Guru
The electical circuit is dead easy - two parallel supplies to the light, one going through the PIR and the other through the two two-way switches. What I'm less sure about is whether the wiring regulations allow it, as it involves a light fed from two different sources. In any event, you would want to make very sure that the PIR was fed from the same circuit as the two-way switching, otherwise when you made one of those circuits dead by pulling the fuse, it would be back-fed from the other - that's how people die.

Under Part P of the building regulations, it would only be legal to have this done by a suitably qualified electrician, you wouldn't be allowed to do it yourself. I merely pass that observation on without making any comment as to whether I think that is sensible or not.

Edit: just to join the dots up, the electrician who you need anyway under Part P will be able to tell you whether is legal under the wiring regs or not.
 
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Andy_R

Hard of hearing..I said Herd of Herring..oh FFS..
Location
County Durham
The electical circuit is dead easy - two parallel supplies to the light, one going through the PIR and the other through the two two-way switches. What I'm less sure about is whether the wiring regulations allow it, as it involves a light fed from two different sources. In any event, you would want to make very sure that the PIR was fed from the same circuit as the two-way switching, otherwise when you made one of those circuits dead by pulling the fuse, it would be back-fed from the other - that's how people die.

Under Part P of the building regulations, it would only be legal to have this done by a suitably qualified electrician, you wouldn't be allowed to do it yourself. I merely pass that observation on without making any comment as to whether I think that is sensible or not.

Edit: just to join the dots up, the electrician who you need anyway under Part P will be able to tell you whether is legal under the wiring regs or not.
This, and it is allowed (otherwise you wouldn't be able to switch your landing lights on and off from both downstairs and upstairs)
PIR is in parallel with the manual switch so either on can switch it on
 

raleighnut

Legendary Member
Some lamps have a facility that bypasses the motion detector, power is taken from the lamp to a switch and the back to the lamp. The lamp does not have 2 power supplies but the switches are wired in parallel so that closing either of them completes the circuit.
 

subaqua

What’s the point
Location
Leytonstone
[QUOTE 3977219, member: 9609"]@subaqua

thanks for all the replies, so if my little diagram makes any sense, then it really is quite straight forward - I did have it in my mind that I would be creating a three way circuit, but clearly that is not necessary. ?

pircircuit_1239_zps3qsq7myt.jpg
[/QUOTE]


love the tree lights ;)

yes thats a circuit that will allow the PIR to switch the lights ON if the 2 ways were in Off position. you wont be able to turn it off using the 2way if the PIR has activated.

There are other ways of doing it with a relay so you can turn off using the 2 way but thats over thinking things .

and as stated earlier it is part P notifiable in England n Wales . not sure what the scots have , but i believe it is notifiable under their building regs and i know of registered sparks up there screwing you over if you do it yourself, to the point it would have been the same to get them to do the work.

a great way to not have a monopoly !
 
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