8067 MANUAL
Matheson Tri-Gas
Page 17 of 21
MINT-0313-XX
Calibration
Over view
The 8067 has two selectable calibration settings; Factory
and Custom. 'Factory Calibration' done during the
instruments manufacture, it can be selected and used but
cannot be changed.
The 8067 is calibrated against a 5000 ppm Helium
concentration and a 0.0005cc/sec (5 E-4) Helium leak rate.
'Custom Calibration' gives the user the ability to calibrate
the instrument. This facility may offer improved accuracy
over the 'Factory Calibration' if the Barometric air pressure
differs from that stated on the instruments Calibration
certificate.
Selecting Factory or Custom Calibration
To select either Factory or Custom Calibration select the
Calibration screen and user the UP and DOWN keys to move
the 'tick / check' under the desired symbol, then Press the 'Esc'
key to exit into the main menu.
'Custom Calibration' can only be selected and used after the instrument has been calibrated by the user. To
do this move the 'tick / check' under the 'Custom Cal' symbol and press the ENTER key.
The 8067 requires either 5000 ppm Helium concentration or a 0.0005cc/sec (5 E-4 cc/sec) leak rate as a
reference. The 8067 automatically selects the type of Calibration media based on which units the instrument
already has selected.
If the 8067 is used to detect leaks measured using 'ppm or mg/m
3
' units, then the instrument must be
calibrated using a 5000 ppm Helium concentration.
If the 8067 is used to detect leaks measured using 'cc/sec' units, then the instrument must be calibrated
using a 0.0005 cc/sec (5 E-4) Helium leak.
Calibration procedure using 'ppm' units
Please read this entire procedure before proceeding with this calibration routine.
* Fill an empty (uncontaminated) sample bag with 5000 ppm Helium gas before
starting the calibration procedure. Also remove the outer grey probe from the 8067.
* Select the 'Custom Cal' symbol from the instruments menu. An option appears
allowing the adjustment of the 'ppm' value to ensure the instrument matches the gas
concentration being used. Use the UP and DOWN keys to adjust between 4900 and
5100 ppm.
* Ensure the instrument is in clean air and then press the ENTER key, the instrument
will Zero, this will take a few seconds but once complete a 'Ready' message will
appear.
* Insert the instruments
probe
fully into the sample bag containing the gas and press
the ENTER key. The instrument will automatically sequence through the cold and
hot stages of calibration but when finished gives a summary of values.
* Press the ENTER key to return back to the calibration option screen. Press the
ESC key to start using the instrument or press the ENTER key to calibrate again.
NOTE: To avoid errors in calibration the following points should be noted:-
* Avoid bending the inner probe as this will affect the 8067 accuracy.
* 8067 can detect changes in Humidity and Carbon dioxide, therefore avoid breathing on the
probe.
* Avoid pressurizing the sample bag as this will cause significant errors in reading
