HP Designjet 2500.3500cp Printer series - Manual (Page 202)

Controlling Image Quality
Servicing the Printheads
9-6
Checking Printheads
The printhead check function prints a test pattern and then analyzes the pattern to
determine if any printhead nozzles are not placing ink on the media correctly. If
nonfunctional nozzles are found, the printer will switch to other nozzles on the
printhead to prevent any degradation in image quality. Eventually it will perform a
set of actions to bring them to a better working condition. In this way, the printer is
able to compensate for nonfunctional nozzles on the printheads.
For most users, the factory default frequency will provide the expected image
quality without any intervention. However, for your convenience, you can set the
check more frequently (up to every page) or disable it.
The Extended margins setting must be selected in order for the leading and trailing
edges of an image to be error-corrected for nonfunctional nozzles. The selections in
this menu are:
For Roll Media The printhead check is done:
■ at the selected frequency
■ whenever you replace an ink system
■ when the power is switched off and then switched back on
■ on request.
For Sheet Media The printhead check is turned off automatically. To check the printheads, load an
A3 or larger sheet in landscape orientation (wide side of sheet first) and select
Check= Now in the Printhead service menu. See page 3-39, Loading sheet media,
for sheet loading instructions.
NOTE If you are using a third-party Raster Image Processor (RIP) to print with your
printer, the printer may not be able to switch to other nozzles. In this case, the
printer will attempt to recover the nozzles.
Now This selection causes the printer to perform a printhead check
immediately.
Off The printhead check functions is turned off. Printhead checks are
done only when you replace an ink system.
Frequency= This setting lets you select the frequency that printhead checks are
made. You can select a printhead check to be done from every tenth
page printed to every page printed.
IMAGE QUALITY
Printhead service
Check=
Default: Frequency=10