Calibrations

The only Calibration that the Printer requires is the Accuracy Calibration which must be performed under certain conditions.

Accuracy Calibration

Purpose

The accuracy calibration (X7axis calibration) procedure is used to correct the end7point accuracy of the media axis. The carriage axis does not require calibration and is used to calibrate the media axis. The accuracy calibration also includes calibration of the optical line sensor on the carriage.

The accuracy calibration is also used to correct the error of the X7axis movement to avoid banding.

Perform the accuracy calibration whenever the:

￿EERO￿ is erased.

￿Electronics module is replaced.

￿Drive roller is removed or replaced.

￿￿edia (X7axis) motor is removed or replaced.

￿Drive7roller gear is removed or replaced.

￿Cartridge carriage is replaced.

￿￿ark encoder is removed or replaced.

￿Optical sensor is removed or replaced.

What is the End￿Point Accuracy Specification ?

The end7point accuracy specifies how accurately a Printer can draw a given length of line. The end7point accuracy specification for the Printers is ± 0.38

mm(0.015 in) or ± 0.2% of the specified vector length, whichever is greater, at 23dC (73dF), at 50760% relative humidity on HP matte film. Use the following formula to calculate the Printer's accuracy:

Measured length ± Desired length

Desired length

x 100 = %Error

What can Affect the End￿Point Accuracy ?

Various part tolerances inside the Printer affect the accuracy (in particular the drive roller). Other outside influences include:

￿￿edia thickness. Thicker media creates longer lines.

￿￿edia expansion. As the media grows, so do the lines.

￿The application software may be instructing the Printer to draw an incorrect line length.

￿The EERO￿ has been cleared. The accuracy constants are stored in this non7volatile memory component.

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HP DesignJet 430, 450C and 455CA Printers

Service Calibrations