Conundrum

Sintra · Apr 2, 2013

Ok I have a friend who breeds some sort of budgies or canaries. What he has is a shed with no natural light and needs a bright (100W) light on from dawn to dusk and a dim (20W) light on from dusk to dawn. The components needed are
1. Lampholder with 100W lamp
2. Lampholder with 20W lamp
3. Photocell
4. Relay with 230V coil
5. Consumer unit with 6A breaker.

Please add to the drawing how you would wire the circuit.

Baker1988 · Apr 2, 2013

Hi i have done a drawing for it but it is rough all free hand and i havnt been to bed yet so drawing will probily be wrong i also have never worked with photo cells or relays.
Here it is

I will explain.
i have wired it in twin + cpc and also threecore + cpc (i know it would probily be in swa or sy or singles "which would be wired differently") i have also left the cpc out of the drawing as we all know where that goes.
The photocell works by when it detects no light the cell will operate and switch.

First i took live and neutral to the photo cell into l and n then i used 3 core from photocell to relay cnnecting live from the photocell to the common of the relay and neutral from the photocell to the neutral of the relay and the switch live from the photo cell to the live of the relay then connected the neutral of the lamps to the neutral of the relay and the live for the 100W lamp to the normally closed side of the relay (as when it is day time the photocell wont operate so no electricity will go down the switch live and operate the relay so it will stay normally closed till night time when the photo cell operates) which will make the 100W lamp on all day till the photocell activates, I have also connected the 20W lamp to the normally open side of the relay so no electric will travel into the 20W lamp untill the relay operates which wont happen till night time when the photo cell operates and send live down the switch live to operate the relay which will then then close the normally open circuit which will turn the lamp on.

I am sorry if this makes no sence im tired haha think its bed time for me

Sintra · Apr 2, 2013

Well done that man.

For ease of drawing lets assume it is all done in singles in conduit. Now we are at this stage and my mate is having a few teething problems that we need to get sorted out. The first one is that when he goes into the shed during the hours of darkness he needs to be able to operate the 100W lamp. (Don't say shine a torch onto the photocell.)

Baker1988 · Apr 2, 2013

if he needed the 100W lamp to work i would put in a override switch in the circuit that he could switch and redirect the perminent live from the common term in the relay to the 100W lamp, You could redirect it in a few places aslong as its the perm live i would do it like this