[How do I?] Safety interlock/shutoff help-slightly off topic

Are you sure your motor controller is not a KBMD rather than a KBMC? My search returned only KBMC - a simple DC controller with reversing.

I just provided the simple control logic - typically 120V - but you can configure as you need and even run it at 24 VDC if you need - just size your devices accordingly.

Braking before you open the doors or braking while the doors are open, etc changes the problem a bit. You can either brake the hard way with mechanical means such as a brake pad arrangement like in your car, or you can momentarily plug reverse by reversing motor direction for some interval and driven by a time delay device as suggested by Mr. Dawson. I don't know what having shop air buys you other than to make the project more complicated than you need, and introduce additional dependencies - for instance, if you rely on shop air to provide braking similar to air brakes on trains, then you need to ensure you have air pressure available before you can even actuate power to the motor, etc.

Probably the best way in your case is to have a spring-loaded mechanical braking system that is always engaged unless power to the motor is available - that is, have a solenoid parallel with the motor control circuit to engage the brakes upon loss of power - whether that loss is because someone inadvertently opened the gates or a command to STOP instruction.
 
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I am buildig a machine that has large rotating frames that could be hazardous to your health if you managed to insert yourself into their travel path. The machine is enclosed is a steel cage with a single opening gate at the front loading area. Large wooden molds are mounted in the secondary frame and it rotates within the larger primary frame. I want to install a safety interlock to prevent the machine operating when the gate is open, and shuts it down if the gate is opened while the machine is operating. In addition I want to wire in a rotating beacon, and an E-stop. My power source is 110 volts. I need some help to identify components and creating a wiring diagram. Anyone here who might be able to help me out? I have spec sheets for all the existing components, the motors etc. Any help greatly appreciated.
Grizzly sells a contactor with emergency stop for real cheap, I got mine on sale for 6.95. I looked at the wiring. Very easy to add more micro switches in line for your door, which would be low voltage to break the magnetic contact. you would need an extra normally open switch or get the dual open/closed switch and serially wire it into the existing switch.
 
One thing I forgot to mention with the air cylinders.
IF you run an air safety system, you will also need an air pressure switch that is wired in the control voltage line so that if there is no air pressure that the machine will not run.
 
I was able to find someone to help me in the tech support group of the company I am buying the controllers from. He has worked out a simple disconnect that will stop the motors if they are running, apply a brake and also prevent start up if the motor is not running when the gate is opened. It has a key that must be in place, locking the gate to prevent someone closing the gate inadvertenly and then starting the motor. I will post pics when the machine is finished so you can see what it all means.
 
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