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Id Like help using a Linear Actuator and a locking mechanism with only one or two momentary switches, not toggle. Ideas? Answered

Hello, I am healthcare professional and a DIY enthusiast, but not mechanically or electrically inclined.  Keep that in mind with your answers.  

I am redoing my closet in the next few weeks and do not have the space or money for a large gun safe.  My idea is that when building this closet I will build a stand up drawer using several slide mechanisms for the motion.  To keep this hidden and secure and darn right cool I envision using a linear actuator to open and close this hidden drawer.  I will also be using one to two electric strike modules to keep this secure.  My goal is to have one secret hidden BUTTON (not switch) that will trigger the locking mechanism and shortly after if not simultaneously activate the linear actuator.  The key here is I want to push a momentary button, not hold it, not use switches ect, just hold it until the drawer is completely open.  

Second motion will be either the same button or a different MOMENTARY BUTTON is depressed activating a reversal on the actuator until fully closed in which the locking mechanism should activate (always closed).  

That is my goal, I'm open to servos and such if anyone can SHOW me how it is done.  If you can show me wiring that would be best as words just don't work as much as pictures or videos for me.  I greatly appreciate all your help in advance and please remember NO TOGGLE Switches or factory wired remote controls.  I'm open to all ideas except those.  Thanks again guys.  Love your work and ideas.  



Correction to paragraph one, I do not want to hold the button until the drawer is open, I want to press it and have it extend.  Thank you


Now you're cooking. Do you want to buy in your actuator ? I would, personally. The rest can be done pretty simply. What's your budget ?

Press button: locks unlock. When locks unlocked, extend actuator. When actuator fully out. Stop.

Press button WHILE the above sequence is happening. Stop, immediately.

Press button AGAIN, reverse sequence.


Yes, that sounds like what I am looking for. I just can't figure out how to do the electrical or mechanical of that. Relays and such I just cant figure that part out. I've read about the DPDT Relay but don't know if it's applicable in this sense. If you have an idea on how to wire this whole set up I would greatly appreciate it.

I HIGHLY recommend you use an off the shelf gadget called a "PLC" to do this then. It will set you back around 100 bucks for what you need, but it will do all you need, reliably.

The one I recommend is called a Millennium III, and its made by Crouzet USA. The list price is around 100 USD for the one you need.


So what that device will allow me to do is program "if" "than" functions? Is it pretty easy to set up and run? I want everything to be 12 volts or 24 volts. I just put it in the input (button) and tell it to run actuator, at set point it stops. hit another button or same button and it can tell actuator to retract and at set point stop? Seems really complicated but I can see it working. How does it do the forward and reverse? Does it reverse the polarity right in the processor? The more I delve into this subject the more I realize I know nothing about it. Thanks

This is a sequencing problem too. You can't move the actuator until the locks are definitely disengaged on the way out, you can't lock the case until the actuator is in.

Think of the problem as moving between states.

You are closed and off. Call this state closed.
Next state is entered by pressing the button.
Locks off. State unlocking
Next state is actuator open. If button again, then actuator stop. State = stopped

Actuator hits limit switch:state = open
Press button state = closing, actuator closes.
Hits closed limit switch. Locks lock on
State= closed.

There will be "limit" switches, which stop the actuator when it reaches "out" and "in"
Forward and reverse is handled by relays built in the PLC.

Okay I'm looking at the device now. What kind of power supply is needed and will the PLC also power the actuator?

The PLC will need its own supply. Some order codes have 110V input, but here, I suggest the 24V DC version, and you sourcing a 24V actuator.

I don't see what this means
"The key here is I want to push a momentary button, not hold it, not use switches ect, just hold it until the drawer is completely open. "

....which I read as "I want to hold a button until it opens"
....but which I can also read as "I want to push a button, and NOT hold it"