TVOC MANUAL
Ion Science Ltd
Page 21 of 32
7 - Calibration
7.2 Setting the ZERO
1 –
Place the calibration magnet over the top right hand corner of the Ion Science logo to enter
calibration mode. The ZERO LED will illuminate and the GREEN STATUS LED will extinguish.
2 –
Remove the calibration magnet
3 –
Insert the calibration adaptor into the sensor cap, attach the carbon filter to the calibration
adaptor. The carbon filter should be attached to the hand aspirator.
4 –
Again place the calibration magnet over the logo. The ZERO LED will flash, during this stage TVOC
displays a direct milivolt (mV) output from the PID sensor.
5 -
Slowly and repeatedly squeeze the hand aspirator to push clean air through the carbon filter and
past the PID sensor. The ZERO LED will stop flashing after approximately 2 minutes.
6 –
Now remove the equipment except for the calibration adaptor.
NB During the Zeroing process the mV reading on the display must reduce to below 30 mV to pass the ZERO
calibration stage.
An acceptable ZERO calibration level will result in the illumination of the GREEN LED.
An unacceptable ZERO calibration level will result in the illumination of the RED LED.
Should this occur
the previous zero calibration level will be used.
Calibration adaptor
Carbon filter
Hand
aspirator
