Placement and Calibration of Sensors
Calibrating Toxic Gas Sensors
EVM Series User Manual
59
Toxic Gas Span Calibration
When conducting a span calibration, the calibrated gas used should match the sensor you will be
calibrating.
NOTE
: For Ozone span calibration, an ozone generator should be used.) If you are continuing from
the Toxic Zero cal section, the screen you will be viewing is the Calibrate/Pause screen. (If
you are performing a Span cal only, ensure you are at the
Start
screen and select the
calibrate menu. Then select the specific sensor by pressing up/down arrows. Press the
Cal
soft key and then press the
Span
soft key. Proceed to Step 2.
Performing a span cal for Toxic gas
1.
Continuing from the zero cal procedures, you should be viewing the
Cal/Pause
screen (as
displayed in Figure 4-17). Press the
Span
soft key.
2.
Apply
the
gas
at full flow rate while observing the “Level” field on the display. Wait for the current
level to stabilize (allow a couple of minutes).
Level
Allow to stabilize
Set
Figure 4-21: Span Calibration
3.
Adjust the span value by pressing
▲
/
▼
Arrows
on the keypad.
4.
Press the
Set
soft key to store the span cal. point. (A screen will appear displaying that you set the
span cal. point.)
