Honeywell VA201T Calibration Handbook page 48

Calibration Handbook
make the final connection due to the inflexibility of PTFE. This minimizes adhesion of the gas to the tube
surface and allows for more accurate measurement.
WARNING
As some test gases may be hazardous, the Flow Housing outlet should exhaust to a safe area.
17. Apply the target gas to the Certified Sensor at a rate of between 0.7l/m and 1.0l/m. Wait for the gas
reading to stabilize before continuing.
NOTE
#ERTIlED 3ENSORS SHOULD BE CALIBRATED AT CONCENTRATIONS REPRESENTATIVE OF THOSE TO BEMEASURED )T IS ALWAYS
RECOMMENDED THAT THE #ERTIlED 3ENSOR IS CALIBRATED WITH THE TARGET GAS IT IS TO DETECT
CAUTION
7HERE THE USER CALIBRATES ANY #ERTIlED 3ENSOR USING A DIFFERENT GAS RESPONSIBILITY FOR IDENTIFYING AND RECORDING
calibration rests with the user. Refer to the local regulations where appropriate.
18. Press ok, the LCD screen displays the message: Calibrating - Wait
19. When calibration is successfully completed the message is displayed: Success! OK:Continue
Ensure that the sensor and the vicinity around it is clear all traces of the calibration gas before continuing.
This is to avoid triggering spurious alarms.
If calibration fails at any point discard the cartridge and replace with a new one.
20. Press ok, the Calibration Menu is displayed again.
21. Press the esc button twice. The Main Menu and then the Gas Reading screen is displayed.
22. Remove the test equipment, refit the sensor cap to the sensor (with reinstalled filter if previously removed
for the test) and return the system to normal operation.
Span Calibration
0
Calibrating - Wait
CO 100 ppm
Span Calibration
0
Success! OK : Continue
CO 100 ppm
Calibration Menu
Gas Calibrate
Gas Challenge
4-20 mA Set Zero
Force 4-20mA
Force Relays
Force Digital
48 Apex Transmitter and Sensor