(In progress)
The Rear Door uses two induction motors operating in servo mode. They are commanded to run the same speed, and they usually do. But the drives are not synchronized. Sometimes the motor positions become too far apart and the door binds.
If the Rear Door becomes misaligned, Investigate the Rear Door drive mechanisms to determine what caused the door to lose alignment.
Probable Causes for Rear Door misalignment
The servos do not know actual position of left and right sides of the door. Servos only know actual motor rotor position.
Indications of proper Rear Door alignment
Left and right drive chains should be under equal tension so that each chain carries part of the load.
Door should not shudder during operation.
Left and right tensioner sprockets should be at equivalent distance from limit switches.
Neither tensioner sprocket should be near the limit switch.
Left Rear Door guide should ride near the center of the track; not dragged to either side.
Drives should not trip on overcurrent.
Probable Causes for Rear Door misalignment
If the Rear Door is closing (moving down) the motor cannot drive the door down. It only controls speed of the door falling due to its weight. If the door jams in the slide the motor will continue to rotate and move its drive chain. Since the door is jammed it does not move. The motor pulls chain from above until the tension becomes so high that the chain skips on the drive gear, or something breaks.
If the Rear Door Seal breaks, seal material can become lodged between the slide and the door. Since the only force on the door in the closed direction is gravity, the door can jam and stop moving. The door will bind.
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Aligning the Rear Door
Prepare the Rear Door for operation
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Click ‘Maintenance Mode’ button to turn Maintenance Mode ON. This allows operation of only the selected motor so that the opposite motor will not attempt to maintain position (as servo motors do).
Aligning the Rear Door
Measure Rear Door position on left and right sides. Decide how far to move either side to bring the door back to level.
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Jog until left and right sides are at same height above the deck.
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When rear Door adjustment is done, restore Normal Rear Door operation
Click ‘Maintenance Mode’ button to turn Maintenance Mode OFF.
Confirm that the Rear Door is aligned:
Operate Rear Door using Cabinet 406 Local Jog Buttons.
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Siemens Starter must be installed on your computer.
Double-click the Rear Door drive configuration file (.s7p) in Rear Door S120 Drive configuration. Starter will open the configuration file.
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Connect ethernet cable between the computer and the Rear Door drive control unit in Cabinet 406
Make Change your computer IP address on the same subnet as the IP address of the Control Unit
to (169.254.11.1, subnet mask 255.255.0.0) to be on the same subnet as the Control Unit.
Connect (Go Online) to the Control Unit
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If you cannot connect, check and fix the communication settings.
On the Project Navigator: Double-Click : Drives → > Servo_02 (or Servo_03) → > Commissioning → > Control Panel
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Assume control of the selected drive.
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Adjust Rear Door height as described in ‘Aligning the Rear Door’.
When Rear Door adjustment is done, restore Rear Door Drives to normal operation
Click Infeed Priority
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Click Return... to terminate the connection to the drive unit.
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