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Wiring relay with limit switch to limit revolution of 12vdc motor to single revolution using a momentary toggle switch? Answered

I am attempting to wire (with my limited electronics knowledge) a 12vdc motor under a hopper to limit the revolution of the motor to single revolution each time the momentary toggle switch is activated.  The motor is connected to a cam that has a hole partially through it that, when the switch is toggled, should fill with product from the hopper, rotate taking the product with it and allowing the product to drop out of the bottom side.  This is designed to dispense a metered dose of product from the hopper each time the momentary switch is toggled.  I have a spst limit switch in place that works as intended mechanically, it is not hooked up.  I also have a 12v relay and momentary toggle switch I intend to use with this project.
My problem stems from my lack of electronics knowledge, I have no idea how this relay, limit switch and toggle switch should be wired together and to the motor and power source.  Any guidance would be GREATLY appreciated!  --MIKE



Best Answer 3 years ago

This arrangement works.

A micro switch has 2 connections and a common COM.

Normally Open NO


Normally closed NC

The micro switch uses the normally closed contact - usually marked NC and it breaks the power to the motor when activated by the cam..

The push button bridges the micro switch so that when you push it the motor starts, The micro switch contact is now closed (NC) and will keep the motor running until the switch is opened by the cam.

The second illustration shows the usual way to meter dry goods from a hopper. A segmented feeder fills from the hopper and is turned to drop the product out the bottom, this way you feed a more accurate amount. If you make the feeder segments very small you can be very accurate and may need to arrange for multiple turns to deliver the right amount.

An alternative is to use a screw feed from the hopper to deliver the product.

metered feed.jpgmotor feed.jpg

3 years ago

Thanks, rickharris, I can't wait to get out and try it. I really appreciate you taking the time to help me out. -- MIKE