5.2 SERVICE PARAMETER SET-UP PROCEDURE
It may be necessary to change service parameters that compensate for certain mechanical
tolerances. These parameters are listed on a label inside the printer and may be changed if
necessary by 94 FUNCT(see 3.5.4). If mechanical parts are replaced some parameters may
have to be reset. New parameter values should be marked on the configuration label.
The service parameters are determined by using 95 FUNCT local print and either 955 and 944
FUNCT or just 943 FUNCT as described below. Parameter values are changed with the A
↑
and B
↓
keys. After changing a parameter, use 95, and either 955 and 944 or just 943, to obtain
new print samples. Re-measure all distances and re-adjust if necessary.
TOP OFFSET is set so the distance from the top document edge to the center of the first line
printed by 95 FUNCT is located as specified by LINE #1 = .XXX (.250 is the default factory
setting) under 92 FUNCT.
LEFT OFFSET is set so the carriage can still move leftward from its home position 0.01" to
0.02" (0.3 to 0.5mm) before it contacts the gate arm that raises the alignment gate.
LEFT MARGIN is set so the distance from the left document edge to the left edge of the first
character printed by 95 FUNCT is 0.20" (5.1mm) if edge sensing is not installed (EDGE
SENSOR parameter will not appear below).
CAR ALIGN is set so either the vertical strokes of H’s printed by 955 FUNCT (firmware E9 and
earlier) from right to left align with those printed left to right or the zeros printed by 943 FUNCT
(firmware EA and later) align. See 5.4.2 for precise adjustment but do not change the belt
tension unless necessary.
FORWARD and REVERSE COMPENSATION are set using either 943 or 944 FUNCT:
a. Procedure for firmware E9 and earlier (see 3.7)
944 FUNCT prints lines of overlapping X's and O’s 10" apart.
Set FORWARD COMPENSATION so that the distance between lines of X's is 10.00"
(254mm) +/- 0.02” (0.5mm)
Set REVERSE COMPENSATION so that the line of O's printed at the top of the page
overlaps the line of X's within 0.02” (0.5mm).
b. Procedure for firmware EA and later (see 3.7)
943 FUNCT prints line pairs with values of –4 t4.
Set both FORWARD and REVERSE COMPENSATION with the value whose line pair is
closest to 10.00" (254mm) +/- 0.02” (0.5mm)
EJECT HOLD OFFSET is set so that an ejected document is still held in the drive rollers but
can be removed by pulling gently on it.
CONFIGURATION selects certain custom operating features and should not be set to a value
other than shown on the configuration label without contacting the factory.
GATE OFFSET is set by the Auto Alignment Gate Height procedure (see 5.4.7)
EDGE SENSOR is set so the distance from the left document edge to the left edge of the first
character printed by 95 FUNCT is 0.20" (5.1mm). This parameter is available on DP8 serial
number 182057 and higher and DP9 serial number 293501 and higher.
NORMAL DARKNESS Lower values reduce darkness and increase ribbon life at normal print
speed. Select the lowest value that provides suitable legibility on thick forms.
CQ DARKNESS similarly controls darkness at correspondence quality print speed.
PRINTHEAD TYPE (early DP8 only) adjusts print pulse timing for two different printheads that
have different drive characteristics. Select AUTO DETECT unless serial number is below
81000. Then select BLACK or SILVER printhead body color. A BLACK head can be damaged
if set to SILVER.
5.3 ELECTRICAL ADJUSTMENTS
There are no electrical adjustments required.
29
