Instrutech CVM211, Руководство пользователя

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Instruction Manual InstruTech CVM-211 " Stinger " Convection Vacuum Gauge Module
InstruTech, Inc page 8
Service
Calibration
Every InstruTech module is calibrated prior to shipment using Nitrogen. However, you can adjust the zero and
span, using the procedure described above. Zero and span settings affect the displayed value and the output
signal. Care should be exercised when using gases other than nitrogen N
2
- See Appendix B for more
information.
Maintenance
Under normal circumstances, there is no maintenance required for your InstruTech module. Good manufacturing
practice suggests the unit should be periodically calibrated against known calibration standards.
Cleaning
The most common cause of all vacuum gauge failures is contamination of the sensor. Contamination can be
generally characterized as either a reaction of process gases with sensor elements, or an accumulation of
material on the sensor elements. Sensors that fail due to chemical reaction are generally not salvageable.
Sensors that fail due to coating may
possibly be restored by cleaning. See Appendix C for a more complete
discussion of contamination and cleaning procedures.
Troubleshooting
Indication Possible Cause Possible Solution
Display is off / blank No power Check cable connections and verify
that power is being supplied.
Readings appear very different
from expected pressure The process gas is different from
the gas used to calibrate the CVM. Correct readings for different gas
thermal conductivity.
See Appendix B.
Module has not been calibrated or
has been calibrated incorrectly Check that zero and span (atm) are
adjusted correctly.
Readings are noisy or erratic Loose cables or connections Check and tighten connections.
Contamination Inspect gauge for signs of
contamination such as particles,
deposits, or discoloration on gauge
inlet. Try cleaning if appropriate.
Gauge cannot be calibrated - zero
and span (vacuum & atm) Contamination. See section below on cleaning.
Sensor failure for other cause. Replace CVM module.
Setpoint does not actuate Incorrect setup Check setpoint setup