Initialize the Machine

To get the Thermal II Head ready for positioning, you need to power up and initialize the device:

15. Power up the machine and monitor the boot up sequence on the diagnostic terminal.

The following two messages should appear:
    >>Datalink: exposure head coming online
    Head initialized successfully

If these messages do not appear, power down the machine, open the access panels, and inspect the cables connected to the head.

If the following message appears:
  incompatible head firmware detected

Then enter the command 5981>>list version and identify the cause of the incompatibility.

16. On Beta 2 and later machines, the serial data communications can be checked with the commands:
    5981>>hotlink enable
5981>>hotlink status
    
    If no error is reported, then the hotlink cable has been installed correctly.
    
    Type 5981>>hotlink disable.

Set the Media Parameters

To set the media parameters for the plate used to position the head:

17. Activate the media type:
    5981>>media N
    where N is the number for the media type that will be loaded on the drum.
18. Load a plate.
19. Display the media parameters:
    5981>>loaded
20. Check the thickness and media index to ensure they are correct for the plate being loaded.
21. If necessary, change the type and media index with the commands:
    5981>>loaded force i3 (changes media index to 3)
    5981>>loaded force t 400 (changes media thickness to 400 microns)

Note:  The write and focus lasers are both disabled if any of the safety interlocked panels are open. The safety interlock override keyswitch does not re-enable either laser. To complete the head positioning, the panels must be closed and the focus laser on.

For details on setting up the Media and Head parameters, refer to the media technical note for the specific media.

Prepare for Head Positioning

22. Move the drum and carriage so that the focus laser is hitting the central area of the plate. Use the commands:
    5981>>carriage moveto 1035mm
5981>>drum move 60
23. Measure and set the surface reflectivity parameter (on a fresh plate). Use the commands:
    5981>>redirect enable
TH2>>eng
TH2>>foc cal reflect
24. Use the result displayed by the command foc cal reflect to use for TH2>>set med <#>: sr <value>
    [Med 0 = Media 1, med 1=Media 2, etc.]
    5981>>redirect disable

Set the Head Position

25. Type the command 5981>>head install on. The monitor will display the focus sensor sum, difference, and error values.
26. Insert the screw adjustment tool (90-1211) through the adjustment hole on the head access panel and into the adjustment screw on the adapter plate.

Inserting the screw adjustment tool

27. Use the precision adjusting screw to position the head until the sum is maximized somewhere between 1300 and 1350. Continue until the error is in the range +5 to -5 microns. The error number is not valid unless the sum is in the acceptable range.
28. Turn off the data streaming with the command:
    5981>>head install off
29. Open the head access panel, then remove the table center panel.

Removing the head access panel

Removing the table center panel

30. Lock the head in position by tightening the six screws that hold the blades to the adapter plate. Start by tightening the middle screw on each side; then alternate from side to side.
31. Replace the table center panel, then the head access panel.
32. Verify that sum and error are within specifications by typing 5981>>head install on.
    If the values are correct, type 5981>>head install off.
33. Check the edge detect position with the command edge test.
    If the error message false edge detected or another error message is displayed, you should investigate to find and fix the problem.
34. Unload the plate from the drum.

• Steps 1-5: Prepare the Head
• Steps 6-10: Mount the Head
• Steps 11-14: Connect the Cables and Hoses
• Steps 35-39: Check and Adjust Image Quality