Placement and Calibration of Sensors
Applying a Gas Sensor
EVM Series User Manual
Applying a Gas Sensor
Gather your calibration gas source, the regulator (if not already connected), inert tubing, the cal adapter
and the EVM with the appropriate sensors installed. After your calibration setup is completed, follow the
proceeding applicable calibration sensor sections.
 Applying a gas sensor
1. Connect the gas
source, regulator and
inert tubing.
2. Slide the inert tubing
over the black nozzle
of the cal cup.
3. Remove the air inlet
cove
r
r
on the EVM.
(See Figure 4-2 for an
example).
4. Place the Cal cup over
the air inlet.
5. When you are ready to
access the Cal screen,
turn on the regulator.
Tubing
Regulator
Calibration gas
source
Cal adapter
Figure 4-17: Applying a gas sensor
Calibrating Toxic Gas Sensors
It is recommended to conduct a zero cal and a span cal with toxic gas sensors. Essentially, a calibration
is conducted by checking the sensors response to a known concentration of a certified calibration gas. It
is important to note that with a zero cal and a span cal, you should be in a non-contaminated
environment when performing the calibration.
It is recommended to calibrate on a regular basis for best results. You will want to perform a zero cal
and a span cal (or adjustment) to properly calibrate a toxic sensor.
The zero and span adjustment procedures for oxygen are different than other gas
sensors.