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Service Guide ML520/521
Chapter 2 Principles of Operation
Printhead Gap Information
Three items factor into printhead gap information.
1.Printhead Gap Adjustment
This is a SERVICE ADJUSTMENT made by a technician. It is covered in Section 3.3 of this Service Handbook.
The Adjustment measures 0.014, +/- 0.001 inches (0.35, +/- 0.03 mm).
2.Printhead Gap Adjust
This is a MENU ITEM in the
It fine tunes the automatic setting of the printhead gap. The settings are 0, 1, and
0 is the factory default.
Use 1 to darken print (if output is consistently light). Use - 1 to lighten print (if output is consistently dark).
3.Gap Control
This is a MENU ITEM in each [Paper Feed] Group.
The Groups are REAR FEED, BOTTOM FEED, and TOP FEED. Gap Control determines how the printhead gap is set.
The settings are listed below.
Auto Gap, Semi Auto Gap, 1, 2, 3, 4, 5, 6, 7, 8, 9 An explanation of each setting follows.
Auto Gap
This is the factory default.
Automatically determines paper thickness of the first page.
During