I have a rotary bar that raises and lowers lights about 45 degrees in each direction. Right now I have a timed relay that stops the bar, unfortunately, the time can easily be thrown out of sync. I have tried numerous "industrial" limit switches with the arms and they just do not have enough precision. I am hoping someone can help.
Here is a video clip of the bar in motion:
https://www.youtube.com/watch?v=YFoRufvPPC8
The bar uses a vehicle window motor and a simple DC circuit. I did not want to get involved with steppers. If someone has some limit switch experience, please share. The hardest problem I am finding is being a rotary bar, at no point is there a way to "push" on a limit switch.
Best Answer
A simple and reliable means to your objective might be magnetic reed switches. A magnet placed on any portion of the moving structure can be used to open and close as the lights rotate.
The circuit for one direction of travel would have the reed switch set to open as the magnet reaches the end of that direction, while the polarity switching circuit receives the other reed switch.
If you can post your circuit diagram, I can be more precise regarding placement of the reed switches, but it's relatively straightforward. When your movement switch is in the "up" position while the lights are down, the reed switch is closed, allowing current to flow. As the light reaches the desired location, the reed switch opens.
When the movement switch is in the "down" position while the lights are up, the same thing applies, as the second reed switch will have closed once the magnet moves away.
I searched for "high current reed switches" and found too many returns to post, especially as the prices range from a few dollars to a few hundred dollars.
Ensure to use a normally-closed switch, as explained on this useful web page.