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wiring limit switches on a linear actuator Answered

I am trying to wiring two limit switches onto a linear actuator. One to stop the extend stroke but will allow you to retract the actuator. The other limit switch will stop the retract stroke but allow you to extend the actuator. The actuator is installed on a door I need it to stop on the extend stroke and the retract stroke so it doesn't damage anything. I have an LACT8-500A actuator and the company doesn't make a limit kit for the adctuator.


I want to open and close a gate using motion activated switches. I have a linear actuator without limit switches. Could your circuit be modified to accomplish this.The original paperwork from surplus center shows plugging into 115 ac with 3 additional leads( red, white, black) controlling direction of rotation--white to L1 and then L2 to red for ccw or L2 to black for cw. Any thoughts?


Ron Lindsey

on Steves wiring diagram, could you tell me the value of R and C on thre motor and what the value of the ac is on the rectifier. Thank you.

Make R 100 Ohm, C 100nF.

The rectifier is there as a convenient bunch of cheap diodes, if its a big motor, go for a mains rated unit.


Personally, I wouldn't make this thing JUST position sensitive, I'd add an over force limit switch too. If someone gets trapped, then either they'll get hurt, or the door will crack. Do you have to provide the forward and reverse power to the motor or is that handled by the actuator ?

I do have to provide the power for the actuator I have run it thur a switch, you turn the switch left or right depending on up or down. Yes I would need to run a over force limit switch.


This is where I'd use relays. Here is a circuit that will work, using relays, but without the force sensing. The "up" switch shown here would be your control button, your limit switch and Force sensing in SERIES


thanks steveastrouk
I just need to calculate the values and it should work for what I need.

Could I use just one over force limit switch for the entire circuit. Use it to sense when the door is completely open or when the door is completely closed and if the door latch was still in place?

You're back to the issue of direction if you only have one. It can be mechanically arranged in one PLACE though, but with two switches there.

.  Wire the NC contact of the Door Opened LS in series with the Open Door SOV.
.  Wire the NC contact of the Door Closed LS in series with the Close Door SOV.

. Solenoid Operated Valve. I was assuming actuator was hydraulic or pneumatic.

I tried that but what happens when the door opened LS is pushed you can't lower the door. The actuator only has two wires for power, so I change the polarity with a switch for up and down.