Zero Calibration - Honeywell VA201T Calibration Handbook

Calibration Handbook
A compressed air cylinder (20.9%Vol oxygen) should be used to perform the zero calibration if the area where
the detector is located contains any residual amount of the target gas. If no residual gas is present then the
background air can be used to perform the zero calibration. Contact your Honeywell Analytics representative
for details of suitable calibration kits.
To calibrate the detector follow the procedure below.
NOTE:
4HE /XYGEN SENSOR DOES NOT REQUIRE A ZEROING PROCEDURE "ACKGROUND AIR  6OL OXYGEN CAN BE USED
TO SPAN THE OXYGEN SENSOR IN PLACE OF A COMPRESSED AIR CYLINDER  6OL OXYGEN  &OR OXYGEN SENSORS
ONLY DO PARTS     IF COMPRESSED AIR CYLINDER IS USED   AND  OF THE PROCEDURE BELOW

Zero Calibration

1. If the ambient air is NOT considered reliable to use to set the ZERO, then remove the weather protection
and fit the Gassing Cap accessory onto the sensor and apply a clean source of zero gas or compressed air.
2. To access the calibration menu, hold the end of the magnet over the switch located at the top center of
the detector display (✓) for at least 3 seconds and then remove.
3. The display will indicate the first configuration mode menu 'SEt CAL'.
4. Put the magnet over the '✓' switch again and move to enter the Calibration menu.
5. The display will show the current gas reading, and the ' ' icon flashes.
6. Observe the Zero reading on the XCD RTD display. If it shows a stable reading of zero gas "0" there is
no need to carry out any further adjustment. If not, it is necessary to adjust the sensor set up follow the
next step.
7. Open the sensor enclosure by unscrewing the sensor cap assembly from the sensor main body and
replace with a Gassing Cap (P/N: 2106D2114) and Flow Housing (P/N: 02000-A-1645).
If the output, with no gas applied, is not zero then adjust the zero potentiometer through the Gassing Cap
access holes to obtain a zero indication.
Connect the regulator to the span gas cylinder. Apply gas at a flow rate of 1 litre per minute for the
recommended application time.
Potentiometer Trimmer
Gassing Cap
Gassing Cap Kit 2106D2114 and Flow Housing 02000-A-1645
Spanner Wrench
142 Sensepoint XCD-RTD