Service; Calibration; Maintenance; Troubleshooting - Instrutech CVM211 User Manual

Instruction Manual

8 Service

Calibration

8.1
Every InstruTech module is calibrated prior to shipment using nitrogen (N
instrument by adjusting zero and span (atmosphere) using the procedure described previously in
titled "programming" (also see User Interface Map). Zero and span (atmosphere) calibration affect the
displayed value and the output signal. Zero calibration optimizes performance of the gauge when operating at a
low pressure range of 1.33 x 10
-3
1.33 x 10 mbar, it is not normally necessary to perform calibration at zero and thus span calibration should be
adequate. If you are able to evacuate your system to below 1.33 x 10
check and set zero if necessary. This will also improve performance in cases where gauge contamination is
causing higher readings than 1.33 x 10
-4
1.33 x 10 mbar. Care should be exercised when using gases other than nitrogen (N
8.2

Maintenance

In general, maintenance is not required for your InstruTech module. Periodic performance checks may be done
by comparing the gauge to a known reference standard.

Troubleshooting

8.3
Indication
Display is off / blank
Readings appear very different from
expected pressure
Readings are noisy or erratic
Gauge cannot be calibrated - zero and
span can't be adjusted
Setpoint does not actuate
Display shows "bAd"
Atmospheric pressure reads too high and
can't be set to correct value
Atmospheric pressure reads too low and
can't be set to correct value
InstruTech
-4 -3
mbar to 1.33 x 10 mbar. If your minimum operating pressure is higher than
-4
mbar, even though the system has been evacuated to below
Possible Cause
No power
The process gas is different from the gas
used to calibrate the CVM211
Module has not been calibrated or has
been calibrated incorrectly
Loose cables or connections
Contamination
Vibration
Contamination
Sensor failure for other cause
Incorrect setup
Sensor wire damaged
Contamination
Sensor wire damaged
Sensor wire damaged
Contamination
CVM211 Stinger
). However, you can calibrate the
2
-4
mbar, it is always a good practice to
).
2
Possible Solution
Check power supply & power cable
Correct readings for different gas
thermal conductivity. See
using the gauge on different gases
Check that zero and span are adjusted
correctly
Check and tighten connections
Inspect gauge for signs of
contamination such as particles,
deposits, discoloration on gauge inlet.
Return to factory for possible cleaning
Ensure gauge is not mounted where
excessive vibration is present
Return to factory for possible cleaning
Return to factory for evaluation
Check setpoint setup
Return to factory for evaluation
Return to factory for possible cleaning
Return to factory for evaluation
Return to factory for evaluation
Return to factory for possible cleaning
section 4.3
section 5 on
Page 23