JUST TOOK THIS JOB ON MAINTENANCE. O. THOMPSON MICROFLITE ULTRA 2000 CONTROLLER ON A HAUGHTON GEARLESS 500 FT A MIN JOB. INTERMITTENTLY SHUTS DOWN WITH A LIMIT BOARD TRIP FAULT. ALSO SEEMS TO HAVE A LOT OF SPEED DIFFERENTIAL FAULTS, ALTHOUGH THEY DON'T SEEM TO CAUSE SHUTDOWNS. ODDLY THE LIMIT BOARD TRIP FAULTS DO NOT ALWAYS HAPPEN AT A TERMINAL LANDING. THIS IS THE M00352 LIMIT BOARD. ANY HELP APPRECIATED.

-- GARY NEWMAN (GN81953@AOL.COM), March 22, 2004

Answers

O.thompson Limit board

Which LED is on when the limit board trip? if it isn't happening at terminal floors see if LED #D10 is on,that would mean that it is not receiving a speed feedback signal.

-- Eric Appana (aappanajr@aol.com), March 23, 2004.

Hi Gary,

In my limited experience with these things, I've found that the limit board can trip if the elevator clips a door lock, or if the car door switch has been opened during travel, causing an emergency stop.

Hope this helps.

-- Justin Ward (liftfixer@hotmail.com), March 24, 2004.

I have had issues with the resistors going out, causing same problems.

-- mike (mikeunderwood@starband.net), March 26, 2004.