MSA TG5000, Руководство по эксплуатации

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Calibration
WARNING!
The green Calibration Cap must be removed from the sensor after calibration. Failure to do so
could restrict gas flow to the sensor and result in erroneously low readings.
Failure to follow the above warning can result in serious personal injury or loss of life.
5.8 How to Calibrate an Oxygen XCell Sensor
An oxygen span gas cylinder is not needed if the sensor is in an area that maintains ambient air
conditions. Follow the same process for XCell sensors as described in section 5.6. When the
display prompts "Apply Span Gas", simply allow the countdown to occur without applying gas.
If the sensor is located in an area of normally low or enriched oxygen, then a 20.8% oxygen
sample must be applied.
5.9 How to Calibrate an XIR PLUS Sensor
A full span calibration is not required for the XIR PLUS sensors. Any degradation of the sensor's
performance is associated with slight drifts in its zero response. Restoring the sensor's zero is
typically sufficient.
The XIR PLUS Sensor Guard comes attached to the XIR PLUS sensor. The XIR PLUS Calibration
Cap is placed over the Sensor Guard so that it is completely covered. Line up the cap so that the
Sensor Guard stem protrudes through the Calibration Cap. Zero or calibration gas tubing is then
attached to the Sensor Guard via the stem.
WARNING!
The green Calibration Cap must be removed from the XIR PLUS after calibration. Failure to do so
could restrict gas flow to the sensor and result in erroneously low readings.
Failure to follow the above warning can result in serious personal injury or loss of life.
NOTICE
If the calibration cap cannot be used (such as for a remote sensor application), ambient wind
conditions must be minimized during calibration to avoid a calibration with increased sensitivity.
The XIR PLUS sensor can be calibrated to a variety of other target gases. Calibrating to a different
calibration gas will align the sensor's accuracy to that gas. Refer to section 9 "Appendix: Calibra-
tion Guide for Additional Gases" for calibration settings. Note that the XIR PLUS sensor is a
general hydrocarbon sensor and calibrating to another gas will not prevent it from seeing other
hydrocarbons in the atmosphere.
5.10 XCell Catalytic Bead LOC Over Range
Catalytic bead sensors require the presence of oxygen in order to sense combustible gas. In the
event of very large combustible gas leaks that exceed 100 % LEL, enough oxygen can be
displaced so that the sensor's response to gas is no longer proportional to the calibration profile.
The XCell catalytic bead has a locking fail safe mechanism that prevents the false reporting of a
safe condition while the % LEL concentration is still above 100 % LEL. When the gas concentra-
tion exceeds 100 % LEL, the sensor will go into LOC over range.
To clear the LOC over range, the user needs to acknowledge and calibrate the sensor. To acknowl-
edge LOC over range, place one finger over each of the EZ touch buttons and hold for 1 second
before releasing. This will allow a recalibration of the sensor to clear the LOC condition.
WARNING!
Ensure that the area has been cleared of gas before acknowledging the LOC Over Range and
recalibrating the sensor.
Failure to follow the above warning can result in serious personal injury or loss of life.
5.11 Calibration Confirmation and As Found/As Left Values
The TG5000 Gas Monitor records the date of the last successful calibration as well as the As
Found/As Left values. This date can then be displayed on the OLED display under the Status
Menu.
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