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How to wire 2 wire actuator with 2 wire Dc adapters as 3 way switches Answered

Trying to figure out the wiring to operate 1 actuator using 2 on/on switches. Anyone care to help out? Actuator has built in limit switches. 24" stroke. It will open all the way and door will be closed and then open all the way when the switch is triggered on either end. Same as a hallway light that operates from 2 location in the house. The tricky part I've found is getting relays and switches to reverse polarity. I know how to wire a dpdt switch to move forward and backward on the actuator. But with another switch to do this I've been told I need relays.

I don't understand the circuitry and tech talk, so please bare with me.
Pictures say a lot, so if you can add photos or links that helps most.


Try this. Notice the changeover switches for relay 3.

Copy of Motor door.png

Ok so the 8 pins on the relays are confusing me now Steve. I dont have to use all of them right? Can You break the wiring down a tad bit easier? For my dumb self t understand? Without the bridge/limits?

You're going to use 5 of them. What relays are you using ? wire over where I put the limit switches in my circuit.


Im using the relays from the link at radioshack you told me about. So, with that outta the way it still leaves the other lead from the 12v dc adapter and the wires to the relays

Here's the original circuit again, without your switches (which go where the "digital timer" is here)

Hen door relays.jpg

To battery +12 and to battery -ve? Theres nothing that shows where the + side goes? and 4 wires off digital timer? This is where it gets me twisted around. I see the two switches with the c, nc, and no. Are those where I wanna put the switches im using? and eliminate the digital timer or do I eliminate the other limit switches there? I do appreciate the help you are giving me but its all very vague sounding to me. Forgive me as I said i don't understand alot of this. If I put together a picture can you maybe draw the wires like a "connect the dots" for me?


The bit that says "to battery +ve" is the bit that goes to the + terminal of your battery. The the bit that says "to battery -ve" is the bit that goes to the - terminal of your battery.

You put YOUR open/close switches where the "digital timer" is, just like I showed in the other diagram.

You forget the limit switches in the diagram above, unless you decide to add safety switches to the door edge.

The diagram above IS a join the dots picture !

I understand that lol but, look up at that picture again for the + side battery theres nothing showing there for where that goes. just the - side and the circle identifies the actuator right? Cause if it doesn't I have no clue where to tie the actuator in. The digital time shows 4 wires off of it. the switches don't have 4 terminals. Thats why i'm asking for the help. That a basic schematic for something else. The picture I added has only the components im using.

The circle is the standard symbol for a motor.
Here's a new version.

door relays.png

Steve... :( I need a little more help if your up to it. I don't understand the switch part. How Do I connect the wires from the relay? To the middle pin of the switch right? You have 2 parallel lines, but are those going to the other switch? Can you break that down for me please?

YOu have 6 contacts on your DPDT switches. Forget 3 of them, on one side.

Wire from the outside pair of one switch to the outside pair of the other. Tie the middle pin of one switch to the relay, and the middle pin of the other to the 12V supply.


Thats what I was affraid of lol Perhaps the center off switch is effecting the operation? Everything else is wired exactly. The red wire goes to the middle of one switch, the bottom 3rd relay wire goes to the middle of the other switch and 2 wires are going across from each of the outter pins

Yes, the centre off is "no-mans land" - you definitely DON''T want a centre off switch !

Ok with 2 dpdt no center off switches, the circuit still does not respond correctly. Everything is followed and when the switch is changed it stops the actuator, and then resumes same motion. Its not switching the polarity to go in reverse. Any ideas?

What do the relays do ? Only ONE should click.

Your actuator has its own limit switches doesn't it ?


All 3 click on not just one. I didn't think hat was right.

It ain't. Depending on the switch, only one or two should click. Check the relay coil wiring.

I checked all the relay coils, its all the same as your diagram. The relays all click 2 in one direction and one in the other direction.

There's a fault in the revised diagram, ther has to be a +12V connection on the middle relay just like the top relay.


Thats it! All finished. Now to run all this wiring lol Thank you very much. Im sorry for being such a pain in the ass. Do you have a paypal account?

I will add that wire when I get home and post results asap

Thank you very much Steve! I appreciate your patience greatly. I do have one last question for you. Where I planned on mounting the switces I already had routered out the holes :( they were setup for the dpdt's. They have 6 terminals on the back. Can I use those still at all? The new switches aren't as wide so just was curious about that

Awesome so just eliminate the limit switches right? wire my 2 wires from the actuator, and the 2 from the dc adapter and where the digital timer is just do it the same on both switches?

Yeah, your actuator has 'em built in doesn't it ? ?? If you find you need safety switches, put them where my microswitches are.


Do you want a system where you can use either of two switches in different locations? See the Wikipedia article on multi-way switches. In the U.S., what you want is called a "three-way switch."

Or do you want the door to work only when both switches are active (in either order)? In that case, just wire the two switches in series.

yes it would be exactly like this but the throw is on off on. so the forward, off and reverse of the actuator.

Stick with a simple two way switch, as I showed. Its very considerably more complicated to do it with a discrete system with latching states, and interlocks.


So just get switches without the center off? Cuz I would be fine leaving the one side to open and then just closew or open the door inside.

Yes, change the state of either switch opens or closes the door.

Ok so with 2 of these new switches. What else besides the relays do I need and how many relays?

three relays, your switches, motor and power supply. The diode bridge helps reduce noise when the motor switches on and off, you could omit it, but I don't recommend it.

Ah, but that' s just a single switch. If you want to have the same trigger in two places, just wire them in parallel (i.e., a circuit-based "OR").

Yea, thats how I had it but I want it to be controlled inside and outside. Behind the bust is one dpdt and in the room is the other. The bust is just the power to the dc adapter for the actuator. Leaving the outside switch in the open position as soon as you turn on the bust it opens the door. To close it I was just flipping the switch behind the bust to close it. But main concern is inside the room, I can't shut it. (well, without being stuck in there) I have a clevis pin to pull the actuator and just roll the door on the rail. For safety

Ah! You really needed to put all those details into the original post (and you should probably edit the text to include them).

You want to have parallel controls on both sides of the door, such that you can open the door from one side, close the door from the other side, and vice versa.

In that case, what you really want is circuitry with a momentary contact switch (SPCO) on each side, wired in parallel to a single set of relays connected to the actuator and limit switches.

Turning either switch to "OPEN" triggers a relay, which stays latched until the door is fully open. The max-open limit switch on the door then de-latches that relay.

Turning either switch to "CLOSE" triggers a second relay, which stays latched until the door is closed. The max-close limit switch on the door de-latches that relay.

You definitely want the clevis pin for safety. In reality, what you should have is a "push to open" button or bar at waist level. If the room is dark and full of smoke you don't want to be hunting around for the clevis-pin ring.

It does have it at waist level. Just in case. The actuaror has built in limits. 24" stroke. I'm not very circuit literate. So, please bare with me. Lol any links or diagrams will be excellent.

Does your actuator include limit switches or not ?

no limits its opening all the way and staying closed and all the way open

Attached is a picture of how to use one switch dpdt to control a DC motor from a DC source.

You can add another switch configured like this in parallel with ONE MASSIVE CAVEAT: If 2 people try to drive the motor in opposite directions at the same time it will be a direct short circuit, making short working of your power supply/switches. If you are cognizant of this, no problem, just only ever use one switch at a time.

OTHERWISE, you could find double pole triple throw (center off sprung center) and imagine the center position on those switches is D output. Feed the 2nd switch's power (a regular dpdt) from the first, so that the 2nd switch only ever gets power while the first is 'off'.


Attached is 2nd (safer) solution.


Buy an automatic gate opener it will have everything you need.