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remote linear actuator Answered

   Hey everyone. I have a question about a  linear actuator that I'm putting on my sawmill to control the throttle. On a sawmill you either need to be full throttle or idle. I've already got the actuator mounted and it works great. Now I need a controller for it. I've got a keyless remote from a auto parts store that I would like to use. I also would like to have a hard wired button. The kicker is that I would like to be able to push a button on the remote or the wired button and the actuator go all the way out. And then push the same button and it come all the way in. The actuator has built in limit switches so it will stop on its on either all the way out or in. This may not be feasible for me to do but I was just thinking by using relays it may be. If I can't use just the one button then I'll have to use two. There should be no need for a stop button since the actuator has a limit switch at both ends. Thanks


Here's the circuit I promised.

You ABSOLUTELY must have a stop switch ! The stop relay here could also force the ignition off.


Motor latched on.jpg

Its late... Tired now................. tried to clean it up for paperMan
Still missing something......... sorry out of time so back to you.

Thanks A.
I'm going to email the OP with a proper PDF. Schematics and this site don't agree with each other.

I love relay logic - my dad taught me all about it :-(


This looks good. Do you think I could get a parts list. The schematics are a little blurry. Thanks


7 years ago

Ive installed set work drives and controls in White Swan.
Are you the Sawyer ?
Is your mill a band saw ?
What is the equipment moving that you want to control ?


I have a band sawmill that I run as a hobby. I've checked into setworks and there a little pricey for me right now. As far as controlling, I want to control the throttle and the canapy up and down by remote. I also want a digital display of the postion of the canapy. I got my hand on proximity sensor and a digital display that I hope it will count sprocket teeth and let me know the height of the saw head.

Almost sounds like the band saw is horizontal.
I am not familiar with "throttle and the canapy up and down"
could you elaborate?

I presume Pictures are hard for new members see example pic of a smart
remote I made as a EE for project, but I need to see your details.

You click on upload from your computer to your message also goes
in your library, manipulation of image except for add / remove is not
possible once uploaded.



Ok, I think I've figured the picture downloading out. It is a horizontal bandsaw mill. Maybe the pictures will give you a better idea of what I'm wonting to do.


It's ALWAYS a good idea to have a stop button. Emergencies are called emergencies for a reason...I'd strongly recommend adding a slap switch for emergency shut off.

Yes, you *can do it with a single button. The push-button power switches used on a lot of consumer equipment is detented, ie, the on position locks,and this could pretty easily be used to trigger a switched crossover, so that in its default position, it would drive right, and in it's dented position the polarity is reversed and it would drive left. (the switch either turns on the relays or leaves them off).

Kiosk class switches seem a good choice for looking, and surplus is probably the most affordable location for a switch.

Presuming your actuator is driven by polarity, that is...If not, well then some other logic will need to be used. for any actuator that uses a PLC controller or any of many little stepper controllers, 90% can be done in programming...

Ideally, locate the relays and power supply coincident with the drive, rather than at the button box or another remote location. It minimizes losses and reduces wiring weight. (the control wiring is the only thing that needs to be added., which is just a four wire cable, two for the relay supply and two for the send to the (+) and (-) relays. two SPDT relays are needed to switch the polarity at the drive.

The trick is finding an industrial strength click switch with those characteristics. (ie, a detented "on" state).

As a safety feature, try to set it up so that if control is lost to the "wand", the drive will shut down automatically.