Product

Lotem^® 400 platesetter

Component

Error

Illegal plate size

Symptoms

A plate is stuck in the platesetter and loading process stops. The error Illegal plate size appears and the status indicator displays Attention as shown.

Cause

One of the following may be the cause of this problem:

• The emulsion on the plate is inconsistent.
• Plate edges have residue or dents.
• The plate is not positioned properly in the cassette.
• The plate is poorly cut.
• The dimensions of the plate in the cassette do not match the plate size parameters defined in the Media Definitions dialog box.
• The centering system is not functioning properly.

Solution

Use the following procedure to troubleshoot this problem.

After making any mechanical change or change to parameters, load a plate to see if you have resolved the problem.

1. Check whether there is emulsion, residue or dents on the plate edges. If there is, load new, clean, undamaged plates.
2. Verify that the plates are centered properly in the loading cassette, and adjust if required.
3. Measure the plates using a ruler or tape measure, and note the measurements.
4. In the Lotem Controller application, select Settings > Plate Definitions, and then double-click Media Definitions. Verify that the plate size is properly defined.
• If the size is properly defined, call your service representative.
• If the size is not properly defined, redefine the media definitions, as described in your user manual.

5. Select DC MOTORS > Centering Motor, and check the value of the MotorVirtual HP APP Value. Adjust accordingly.
6. Select DC MOTORS > Centering Motor, and increase the Counts Inside Window Tolerance parameter to compensate for small distortions in the plate size.
7. Open the top door and inspect the centering pins for dirt or emulsion:
• If the centering pins are clean, proceed to step 8.
• If the centering pins are not clean:
1. Clean the centering pins with a lint-free cloth dampened with alcohol.
2. To make the centering pins less sensitive to emulsion residue, select DC MOTOR > Centering Motor, and increase the value of the Times To Check Centering Detection parameter from the default of 50 to a higher value, such as 100 or 150.
8. Leave the door open and use a cheater to load a plate. Watch carefully to see whether the pins touch the plate.
• If the pins touch the plate, proceed to step 9.
• If the pins do not touch the plate:
1. Remove the plate.
2. Inspect the centering system for dirt or debris, and clean or remove any debris, as required.
3. Inspect the disposal rollers for foreign objects.
4. Inspect the centering pins driving chain to verify that it is intact and properly assembled. Adjust or replace the driving chain if required.
5. Run diagnostics for the centering motor encoder, and replace the centering motor, if required.
9. Check whether the centering pins detect the plate, as follows:
1. In Lotem Controller, in the Hardware directory, select Loading System > Loading Plate to Drum > Centering System, and then double-click Centering Motor Plate Short Detector.
2. In the Centering Motor Plate Short Detector dialog box, check the detector status. The detector status should be ON.
• If the detector status is ON, check the following:
1. Check the speed of the centering pins. If the pins move toward the plate too quickly, they can hit the plate and bend it.
   Select DC MOTORS > Centering Motor, and reduce the value of the Centering Speed Value for Second Detector parameter, if required.
2. Check the position tolerance and adjust, if required.
3. Check the voltage for the short detector and adjust, if required.
• If the detector status is OFF, the pins do not detect the plate.
1. Check the short function between the centering pins using a multimeter.
2. If there is no short, identify the board that controls the electronic functioning of the centering system, and run diagnostics on the board.
3. If diagnostics fail, replace the board.
If the problem persists, escalate the problem.

Technical contact(s)

Mario Amir

Submitted by

Mario Amir

Date submitted

26 Aug 2003