DH Instruments PPCK PLUS, Operation And Maintenance Manual

Page: 141 / 150

PPCK+™ Operation and Maintenance Manual
Page 133
©2001 DH Instruments, Inc .
Table 18. Troubleshooting Guide (Continued)
SYMPTOM POSSIBLE CAUSE SOLUTION
Apparently inaccurate pressure
measurement/control and
<h>
is displayed on top line of
screen.
An unplanned "head"
correction is active or head
height or gas is incorrect. Remove or change "head"
correction (3.2.7).
Apparently inaccurate pressure
measurement/control. Incorrect pressure units and/or
measurement mode (gauge or
absolute). Set desired pressure units
and/or measurement mode.
Consider reference
temperature if unit is inWa
(3.2.2).
Apparently inaccurate pressure
measurement/control. Reference pressure transducer
calibration coefficients have
been altered. Check and correct calibration
coefficients if needed (5.2).
Apparent inaccurate pressure
measurement/ control. AutoZ has been run and turned
ON with an incorrect standard
for zero. Check value of ZOFFSET.
Rerun autoZ with a valid ZSTD
reference (3.4.1).
Will not vent. System is vented but does not
indicate zero because
measurement mode is
absolute. Check measurement mode
setting and current value of
atmospheric pressure if
absolute (3.2.2).
Will not vent. VENT port is plugged. Open VENT port to
atmosphere.
Will not vent. Exhaust valve not operating. Check that high pressure valve
drive air supply is connected
and of correct pressure (2.3.6).