Chamberlain LiftMaster Professional SL540 Manual page 26

Operator runs in wrong direction
" Operator's main power is out of phase (three phases only)
➤ Turn off the unit's main power at the breaker and swap any two power leads at the operator's main power switch. Apply power and retest the operator. See
important note on page 14.
Operator runs but then stops and reverses direction
" Entrapment (force pot) incorrectly set
➤ This pot must be set so that the gate will run smoothly normally and reverse when encountering an obstruction. See page 21.
" Gate is binding or not running smoothly
➤ Disengage the manual release and roll gate open and close by hand at normal operating speed. Make sure that the gate runs smoothly and does not bind.
If the gate is hard to move or binds, repair the gate.
" Clutch is not adjusted properly
➤ Adjust the clutch so that the operator can move the gate throughout its travel without slipping but will slip when the gate hits an obstruction.
" Brake is not functioning properly
➤ Make sure that the brake operates correctly. The brake should disengage when the contactor activates and engage when the contactor releases.
" Observe red LEDs D29 and D31
➤ Both LEDs will indicate the activation of entrapment protection devices on terminals J1-9 and J1-10 on the GL board. Remove the devices and retest. If
the operator now runs without fault, check those accessories as well as their wiring.
" Hall Effect Sensor is not aligned/adjusted correctly
➤ Make sure that the sensor is adjusted so that it is centered over the limit shaft's magnet and is .010 - .015 of an inch (business card thickness) from the
magnet.
➤ Replace the sensor if it is adjusted correctly but continues to fail.
Motor runs but gate doesn't move; operator stops and alarms
" Clutch is not adjusted properly
➤ Adjust the clutch so that the operator can move the gate throughout its travel without slipping but will slip when the gate hits an obstruction.
" Operator's manual release is engaged
➤ Make sure that the unit's manual release is not engaged. The unit's manual release, when engaged, will set off the entrapment if the gate is given a
command to move.
Operator opens immediately upon power up and does not close
" Check the red input status LEDs, D11-D13, for indication of an active or malfunctioning accessory
➤ If any red LEDs are on, check the corresponding input. An installed accessory may be wired incorrectly or malfunctioning. Remove the accessory and test
the operator.
➤ If the soft open or interrupt loop LED is on, make sure factory plug-in loop detectors are working properly and appropriate loops are installed on the loop
input terminals P1-P4.
Operator has trouble learning the motor
" Operator's manual release is engaged
➤ Make sure that the unit's manual release is not engaged. The unit's manual release, when engaged, will not allow the entrapment sensor to provide
feedback to the GL board when the operator is moving.
Programming changes do not effect the gate
" Check the save switch on switch S1-1
➤ If the switch S1-1 is in the on position, any subsequent programming changes will not affect the gate. To make programming changes, switch S1-1 off,
make desired changes, and then switch S1-1 on.
Gate edge pauses gate when struck during opening
" Open obstruction input is programmed incorrectly
➤ The open obstruction input has been programmed to function with photo eyes, not gate edges. Refer to page 23 and reprogram the obstruction inputs for
correct operation.
Gate does not activate timer to close after the close photo eye is broken
" Close obstruction input is programmed incorrectly
➤ The close obstruction input has been programmed to function with gate edges, not photo eyes. Refer to page 23 and reprogram the obstruction inputs to
match the accessories that are installed on operator.
Radio controls will not close the gate from the open limit
" Radio terminals R1-4 are factory configured for commercial radio function
➤ Configure terminals R1-4 for residential radio function by performing the following modifications:
1. Locate and disconnect the end of the wire running to terminal 6 (TB6) from R4.
2. Connect the end of the wire removed from terminal 6 (TB6) to terminal 1 (TB1). Refer to page 36.
T R O U B L E S H O O T I N G c o n t ' d
26