Ion Science Cub - Manual (Page 34)

CUB MANUAL Ion Science Ltd
Page 34 of 42
Unrivalled Detection. www.ionscience.com
Maintenance
Calibration
Ion Science Ltd recommends an annual service and calibration for users who require a traceable calibration.
During this service the lamp and detector are brought back to factory specifications and a Factory Calibration
is carried out and data logged.
Due to the linear output of the Ion Science PID detector, a two-point calibration is used. Cub scales its linear
output across a ZERO level (clean air reference) and the SPAN 1 user defined gas concentration.
The Cub is calibrated at ion Science after manufacture; please note that subsequent calibration will overwrite
the factory calibration. To calibrate the Cub first set up the parameters in Cub PC
– see the ‘Cub PC
Software’ section of the manual.
Ensure you have the cylinder(s) of gas, regulator(s) and / or a zero carbon filter for your Cub on hand before
starting the procedure. Alternatively a known clean air supply may be used as the ‘zero’ gas. Please ensure
you are familiar with the entire calibration procedure before attempting to calibrate your Cub.
If using a carbon canister for the Zero stage, use a short length of Tygon pipe to connect between the
Carbon canister and the Calibration Zero inlet connector.
Connect the Zero and Span gas by pushing 5mm Tygon pipes onto the push fiitings on the back of the
Calibration docking station. Connect the Zero gas to the left position and Span gas to the right position.
The middle position is unused.
The Zero and Span times will be affected by the length of pipework between the gas source and the
Calibration dock. For best results, Ion Science recommends that lengths of pipework are kept to a minimum.
The shorter the length of pipework, the less gas is used to calibrate.
The table below assumes the use of 5mm ID Tygon pipe.
Pipe length Zero Time (sec)
Span Time (sec)
100mm 10 22
200mm 12 24
300mm 14 26
400mm 16 28
500mm 18 30
600mm 20 32
Minimum gas concentration is 2 ppm. Demand flow regulators must be used to supply gas to the calibration
dock. They must be able to supply 0.3Litres per minute (300ml/min). The dock draws as much gas as it
needs from the regulator (around 200 ml/min).