Contactor Conundrum.

La Poste · Mar 23, 2012

Greetings.

I have bought myself a Contactor to wire into the garage lights so they switch on when the electric garage door is raised.

[ElectriciansForums.net] Contactor Conundrum.

Unfortunately it did not come with any literature and seeing as how this is the first time I have ever wired one I thought I would ask here for a bit of advice.

I am guessing that terminals 1 and 2 are for the feed signal from the door and terminals 3 and 4 are for the load which is the supply to the lights.

Is this correct?

The garage door has a small light that illuminates when the door is opened and I was thinking of wiring the feed to the Contactor in parallel with the light.

The supply to the garage lights (load) would go from a 6 Amp MCB, through the Contactor then to the lights and then back to the neutral of the board so the Contactor will be wired in parallel with the garage door light as a feed and in series with the garage lights which are the load.

Can anyone help me with this one?

Thanks very much.

Darkwood · Mar 23, 2012

A1 and A2 is the coil when you apply 230v to the coil it will close the contactor, check your garage door light is the same voltage as the coil on the contactor, then bring your mcb feed into terminal 1 and switch out of terminal 2, is the light you want to bring on existing and controlled by a switch or is it an independant light running of the contactor only.

mechelec · Mar 23, 2012

Look at the front of the contactor and all should be clear. Clue is A1 and A2 are coil terminals

jumpin jax · Mar 23, 2012

perhaps La poste is not seeing the wood for the trees, the A1 and A2 screws are the ones dead in the middle in front of the double pole inputs and outputs

Guest123 · Mar 23, 2012

The issue I forsee is that the lamp in the door motor unit may be a different voltage to the coil contacts in the contactor.

Also, terminating additional cableing to the lamp terminals may be a right PITA.

Knobhead · Mar 23, 2012

A simple limit switch on the door would solve the problem. Take the contactor back and get a limit switch.

La Poste · Mar 23, 2012

That's great thanks.

I didn't realise A1 and A2 had terminals behind the screws, I was being a bit thick, I couldn't see the terminals at first glance.

The supply/feed to the garage lights will feed two switches.

Each switch will feed one bank of lights, each bank of lights consists of 2 six foot fluoro's so in total there will be four six foot fluoro's supplied by two switches.
Each pair can be switched independently.

So this Contactor is double pole with line load going through 1 and 2 and load neutral going through 3 and 4.
Is this correct?

The lamp in the garage door is definitely 230 Volts I checked.

Also the garage door light/ control signal has a timer built in and so this timer will be handy for turning the garage lights off automatically after about two minutes.

I am not sure what a limit switch is, I shall have to do some reading.

Knobhead · Mar 23, 2012

Does the indication lamp remain on when the door is open or just when the winding motor operates? If it’s on all the time the door is open your OK, otherwise you’ve got problems.

La Poste · Mar 23, 2012

It's a small lamp, low wattage 230V light bulb at the top of the control unit.

When the garage door is switched to open the lamp illuminates and stays illuminated for about two minutes after the garage door has finished opening then switches off.

The same is also true when the garage door shuts. The lamp illuminates when the motor kicks in and the lamp stays illuminated for two minutes after the door has shut.

If I can get the control feed wired OK I will take the supply from a 6 amp MCB, through the Contactor, through the switch and thence to the lights and keep my fingers crossed.

Darkwood · Mar 23, 2012

You could wire coil as suggested and have a feed from light switch feeding 1 and looping to 3, then 2 is switch to one bank of lights and 4 is switch to other bank of lights, you dont need to run neutral through contactor, this way all lighting will work via contactor.

Marvo · Mar 24, 2012

Some garage door unit lamps are supplied via a solid state device ie diac or triac. I would check the circuit first and if the lamp isn't supplied via a relay then use a separate limit switch to operate the contactor as previously suggested.

Also sometimes the garage door unit flashes the lamp several times before the door opens or closes by means of a warning. This would play havoc if you're using the contactor to supply fluorescents.

telectrix · Mar 24, 2012

why not just fit a PIR to switch the lights on, leaving the manual switch in parallel. that way the lights will come on if you enter by the back door as well.

Marvo · Mar 24, 2012

Yep, I agree. Even if for some reason a PIR won't work I can't help thinking there will be an easier way to achieve the goal.

Knobhead · Mar 24, 2012

If you want the lights to operate with the door I’d go for a limit switch. As Marvo pointed out the lamp could have a solid-state driver, which could be damaged by the inductive load of the coil. If you want to use the contactor try this

View attachment 11419

Des 56 · Mar 24, 2012

telectrix said:
why not just fit a PIR to switch the lights on, leaving the manual switch in parallel. that way the lights will come on if you enter by the back door as well.

I have done that on many occasions,the folks are generally thrilled by the magic of it all

Simple and easy to please folks with a simple system