Table 16 - Troubleshooting Guide - Part 2
Symptom
"Stop" button doesn't
stop the door
Door reverses to fully
open position after the
door closes and
reaches the floor
Door doesn't open or
close, motor hums or
blows the main breaker
Motor hums when
"Open" or "Close"
buttons are pressed
Motor fails to shut off
at fully closed or fully
opened positions
Motor turns but door
does not move
Limit switches do not
hold their settings
Poor radio range
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Probable Cause
Two 3-push button stations (or more) are
connected in parallel.
The "Close" limit switch is not being
engaged by travelling cam.
An "Open" command is being given.
Mechanical door lock is engaged.
Door is jammed.
Brake doesn't release, if applicable.
Loose wire on solenoid brake, if applicable.
Faulty solenoid brake, if applicable.
Loose motor wires.
Defective capacitor.
Defective limit switch.
Limit cams are not adjusted.
Limit drive chain is broken.
Loose sprocket on limit shaft.
Limit shaft does not rotate.
Sprocket key is missing.
Drive chain is broken.
Clutch is slipping.
Loose drive or limit chain.
Limit cam retaining bracket is not engaging
in the slots of the limit cams.
Limit cams are binding on shaft threads.
Limit shaft has a slight "play".
Transmitter battery is low.
Radio antenna is not properly positioned.
Ambient radio, environmental or building
structure interference.
40
➔ Verify and correct wiring (Stop
buttons in series, only Open & Close
in parallel).
➔ The "Close" limit switch needs to
be adjusted properly at the end of
travel.
➔ Verify "Open" push-button or any
opening device for short-circuit.
➔ Release the door lock.
➔ Verify manual operation of door.
➔ Verify and adjust brake tension.
➔ Verify and correct wiring.
➔ Replace.
➔ Verify and correct wiring.
➔ Replace.
➔ Operate limit switch manually while
door is moving. If door does not stop,
replace the switch.
➔ Verify and adjust.
➔ Replace.
➔ Tighten set screw.
➔ Verify and replace accordingly.
➔ Replace.
➔ Replace.
➔ Adjust clutch to proper tension.
➔ Adjust chain to proper tension.
➔ Be sure it is engaged in slots of
both cams.
➔ Lubricate shaft threads. Limit cams
should turn freely.
➔ Verify and adjust.
➔ Verify and replace battery.
➔ Make sure antenna cable is not
bent. Cable should be passed through
control box.
➔ Check connection of plug-in
antenna. If required, add an external
antenna (socket on receiver available).
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Suggested Action
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