I have a problem with a projector lift. When the system is turned off, the projector lift retracts into the ceiling. Every now and then the lift will drop about 1/8in and tried to pull itself back up, only to sit there and vibrate. The result being a vibrating ceiling. The salesman sold the wrong size lift. The projector is a little too heavy for the lift. The manufacture will not let us replace the motor with a stronger one, unless we rip it out the ceiling and send the whole thing back to them.

I am looking for some kind of 12v timed and/or triggered cut off switch, which would turn on when triggered by a constant 12volt signal, and turn off 30-60sec after the 12v signal is turned off.

If anyone has any ideals or other suggestions please feel free to join in.

I just ripped one out of a celing for the second time. The manufacturer (INCA) admited they had a problem with this 12vdc unit, and will replace it with a 120vac unit. (Thank you INCA for standing behind your product. I will continue to use INCA lifts)

Your plan may solve the vibrating ceiling, but how long will the lift last if it is under sized.

My suggestion would be to replace it with the right size lift.

John

Try this company http://www.relayspec.com we've used them for years they have every imaginable timer and relay you could want. from what you've described the lift is droping below the limit switch settting and the motor is trying to lift it back up to the limit switch preset. There propably isn't enough tourque to lift it up because there isnt enough momentum and it is hitting the flange around the edge of the lift. My guess is that the motor will eventually shut off when it goes into thermal protection but the process will start over again when the motor cools off making for one annoying evening. if you don't correct this problem you will eventually fatigue the motor and it fail making your removal of the lift impossible since it propably fail in the closed position with the projector in it. I would try to replace the lift if I were you otherwise make a power interruptor to the projector lift when the system is not in use by using a switched outlet on the a/v equipment and a relay. Good Luck

audiotec