CARRIAGE PASSES THE STOP BLOCK / WON'TSTOP RUNNING The limit switch activator arm (roller) is missing the stop block. Adjust the activator arm on the limit switch and/or the stop block to ensure proper contact of the limit switch in the up and down positions.
The VFD is defective. See the Control Panel troubleshooting guide.
The limit switch is defective. Check for input status on PLC when toggling the switch.
AFTER CYCLE START, THE CARRIAGE DOES NOT GO UP OR DOWN The carriage speed is set too low. Increase the carriage speed potentiometer on the control panel.
The limit switches are making premature contact. When both of the L.S. are not in contact with anything and *Autoheight switch to off, input #0.7 and #1.0 on the PLC should light up. Move the stop block if the limit switch touches it. Shorten the shaft of the limit switch. The rail may need to be straightened if the limit switch touches it.
The VFD has registered a fault or is defective. See the Control Panel troubleshooting guide.
The photoeye labeled PE-1 is not seeing the load. When the photoeye is seeing the load and *Autoheight switch to on, input #6 on the PLC should be off. Check photoeye adjustments in the electrical schematics and then check the sensitivity of the photoeye.
The motor-to-transmission key is sheared or broken. Replace the motor-to-transmission key.
The carriage lift chains are too tight or guides are binding. Reduce tension on the chains and align guides.
The table or rotary arm's proximity sensor is not counting. See if input 1.1 on the PLC flashes 16 times(table) 32 times(rot arm) per revolution. Realign the proximity sensor. If the problem reoccurs, replace the sensor.
CARRIAGE DOES NOT STOP AT THECORRESPONDING PALLET HEIGHTS Autoheight photoeye does not see the load. Check photoeye adjustments on the electrical schematics & check the sensitivity of the photoeye.
The autoheight function is turned off on the control panel. Turn the autoheight function on.
Photoeye is dirty. Clean the photoeye light emitter's lens.
The color of the load is black or it is non-reflective. Increase the photoeye sensitivity enough to see the load without seeing something else when the photoeye clears the load.


NOTE: For WRT models, there may be a loss of power through the slip-ring (commutator) assembly. This will interrupt power feeding devices on the rotary arm or signals going to the PLC. Remove commutator dust cover and inspect for carbon build-up or broken/worn brushes.