Specifications

WESTLOCK CONTROLS CORPORATION
280 MIDLAND AVENUE, SADDLE BROOK, NJ 07663 TEL: [phone] FAX: [phone]
www.westlockcontrols.com
1/12/10 TECH-439/D.W.O. 19024 Page 39 of 58
Message Meaning Solution
Input
pressure
unstable
Pressure was
unstable during
calibration
Check:
 Pressure supply stability
 Actuator and tubing leaks
 Manifold and transducer assembly are tightly coupled to the
enclosure and there are no leaks
 Check if the cable between the inner canister and the
pneumatic transducer assembly is tightly connected
 Actuator/Valve assembly integrity
 Perform a full auto CAL
 Call factory for additional support
HALL span
too small
Hall sensor
used to read
position is
unstable
Check:
 Hall sensor connector and cable, especially if remote (see
Figure 3-4, connector J8)
 Magnet assembly:
o For rotary magnets check if it is not rotated 90
degrees (see figures 3.2, 3.3 and 3.4).
o For linear magnets, check if the magnet assembly
center is matching the actuator mid position (see
figures 3.5, 3.6 and 3.7)
 Remove power for at least 1 minute, perform a factory default
(see Appendix I) and retry the calibration
 Grounding issues, cable shield is properly grounded;
positioner ground is properly connected to a clean ground
reference.
 Sources of electromagnetic noise too close to the sensor or to
the positioner cables, like AC cables for motors, inverters etc
 Try to replace the Hall sensor and/or the magnet
 Call factory for additional support
A2D span
too small
One or more of
the analog
variables
(position,
pressure or loop
current) does
not have
enough span to
calibrate
accordingly
Check:
 Hall sensor connector and cable, especially if remote (see
Figure 3-4, connector J8)
 Magnet assembly:
o For rotary magnets check if it is not rotated 90
degrees (see figures 3.2, 3.3 and 3.4).
o For linear magnets, check if the magnet assembly
center is matching the actuator mid position (see
figures 3.5, 3.6 and 3.7)
 Set-point stability, current generator, grounding issues, cable
shield is grounded properly, cables entry ground is properly
connected to a clean ground reference.
 Pressure supply stability, actuator and tubing leaks
 Remove power for at least 1 minute, perform a factory default
(see Appendix I) and retry a full auto CAL
 Grounding issues, cable shield is properly grounded;
positioner ground is properly connected to a clean ground
reference.
 Sources of electromagnetic noise too close to the sensor or to
the positioner cables, like AC cables for motors, inverters etc
 Call factory for additional support