If that is the unit I am thinking about, they only made it for one year. That should tell you something!
The safety monitor board on the door taps into the normal running and safety circuits, and reports what it sees with the LEDs. If you have the right print, you can see where these taps are placed, and that will explain their meaning. if anything isn't just right, the safety monitor vboard has the ability to drop a relay, opening the safety circuit.
I'll look around, and see if I can find the print. We lost that job, so I don't know if we still have it. If we do, I'll shoot you a copy.
