MAN-0093 Rev 0 Oxygen Sensor
June 2008
Net Safety Monitoring Inc.
14
5.1.3
Calibrating with the Millennium II Basic Transmitter.
When calibrating use 20.9% air from canister or surrounding air, provided it is not contaminated. It is
recommended that this sensor be calibrated every 3 months (90 days) to ensure proper functioning.
Follow the steps below for Calibration / Normal Calibration Procedure.
1.
Confirm successful power up of Transmitter, (green blip/blink of status LED every second: no fault
indicated).
2.
Bypass any output alarms (recommended).
3.
For analog model connect a standard current meter to the Transmitter’s Test Jacks (not required but
gives visual confirmation).
4.
If a gas canister is being used for calibration, apply gas (air ) two minutes before calibration is initiated.
5.
Press and hold the “
push button
” (or activate the “
Reed switch
” using the magnet) for at least 15
seconds, the status LED flashes green fast, and then goes solid green (first solid green). Keep holding
“
push button
” or magnet, after which, status LED goes solid red, release “
push button
” or remove
magnet.
6.
When the current output is 3 mA (indicated by analog models) and the Status LED is once again solid
green (second solid green), apply zero gas (clean air) at a rate of 0.5 liter per minute. If the surrounding
air (ambient air) is clean (free from contaminants), then use the surrounding air for calibration.
7.
Continue applying clean air when the current output is 3.3 mA(indicated by analog models) and the
Status LED is flashing red. If the surrounding air (ambient air) is clean (free from contaminants), then
use the surrounding air for calibration.
8.
If long tubing runs are being used, increase the air flow rate (1.0 liter per minute) to ensure tubing does
not affect calibration results.
9.
When calibration is completed the current output will be 3.6 mA (indicated by analog models) and the
Status LED solid green. After which, the Status LED will then blip green to indicate normal operation.
Note:
A zero / calibration can be done, by releasing the push button at the first solid green in step 5 above
and applying clean air. Zeroing the sensor will also result in calibrating, since the sensor is an oxygen
sensor.
