Lighting circuit controlled by a time clock and photo cell through a contactor

[Sean burge]

Hi gents,

I am going to a job to install some new external lighting on a factory on Monday. There are 5 new circuits to run in total. They want these to be controlled by a time clock an photo cell but also run through a key switch and contactor. It’s been some time since I wired contactors and was just looking for some advice on it or if someone could provide a wiring diagram I would be very grateful

Thanks in advance

 

[Des 56]

Timelock with Photocell then Contactor with a Keyswitch - https://www.electriciansforums.co.uk/threads/timelock-with-photocell-then-contactor-with-a-keyswitch.118798/

I have posted you a link to a previous thread
Have a read then look at the examples given by Richard Burns
He is the forums wizkid when it comes to displaying drawings and if its not what you require,no doubt he will be along

 

[Lip.82]

 

[Lip.82]

Hi
Sorry about the bad drawing, it's one I done a few years ago but I kept it on my phone to refresh my memory as I don't wire these on a daily basis.
The neutral is in a connector block in the key switch.
Hope that helps

 

[westward10]

Think we need to know the purpose of the key switch. Override, means of turning them off, em ltg test facility??

 

[marconi]

Post #3 wires the functionality:

If [ T is On and ( P is On or K is On) ] then L is On

where T is the timer, P is the Photocell, etcetera.

As Westward10 said, what are the conditions for the states of T, P and K that cause L to illuminate?

Be sure beforehand otherwise you may have to come back and rejig the wiring. Ideally ask the client to write it down for you.

 

[Sean burge]

The purpose of the key switch is to test the emergency lights in the circuit. So when the key switch is activated the lights should enter into emergency mode.

 

[marconi]

The purpose of the key switch is to test the emergency lights in the circuit. So when the key switch is activated the lights should enter into emergency mode.

This is part of the answer to the functionality: you now need to know how the client wants the photocell and timeswitch to work together or independently to control the lighting.

I recommend you have a go at writing an 'If'-then' statement as I did.

The way the T, P and K should be wired to control the contactor and thence the lighting can then be derived from it.

Is the emergency lighting 'maintained' or 'non-maintained'? Is it separate to the normal controlled illumination or a contributor to it?

 

[westward10]

I would use a separate circuit for the control which will be the clock which controls the contactor/s via the photo cell. I assume the external lights are maintained so the permanent charge supply must not be isolated by the contactor/s so take this supply from the unswitched side of the contactor/s via an identified test facility. If you have five circuits you will probably need two suitably rated contactors and if each has emergency lighting then five test facilities.

 

[Toneyz]

On the contactor control circuit I tend to go through the p/cell first then the time clock relay as there is always a delay for the p/cell to operate .

 

[Dozer 73]

I would use a separate circuit for the control which will be the clock which controls the contactor/s via the photo cell. I assume the external lights are maintained so the permanent charge supply must not be isolated by the contactor/s so take this supply from the unswitched side of the contactor/s via an identified test facility. If you have five circuits you will probably need two suitably rated contactors and if each has emergency lighting then five test facilities.

You could also put emergency lives through norm closed contractor and 1 key sw , poss more costly ??

 

[westward10]

You could also put emergency lives through norm closed contractor and 1 key sw , poss more costly ??

Yes I thought the same but I think that may over complicate it for the OP.

 

[Lip.82]

Think we need to know the purpose of the key switch. Override, means of turning them off, em ltg test facility??

Hi
The means of the key switch is to over ride the photocell when fault finding. Easier and quicker to flick a key switch than get ladder out and get up to a photocell and cover it up

 

[westward10]

Hi
The means of the key switch is to over ride the photocell when fault finding. Easier and quicker to flick a key switch than get ladder out and get up to a photocell and cover it up

It is an emergency lighting test facility.

 

[Lip.82]

We use this for outside lights. Where there are no emergency lights