MSA DF-8500, User Manual

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DF-8500 Gas Detector
[M-00] -- Alarm(relay)reset
This menu item is used to reset the alarm of detector. This menu item will be displayed
only when the relay is set as locked.
(1) Press “+” to select the menu item M-00.
(2) Press “ON” , and the menu of entering password appears.
(3) Enter the password (see Section 4.4).
(4) If the password is correct and the current alarm condition doesn’ t exist, then the
locked alarm is reset.
[M-01] -- Zero calibration
(1) Press “+” to select the menu item M-01.
(2) The display displays zero countdown time after pressing “ON” , with a default value
of 30 seconds.
(3) Apply zero gas (Pure Nitrogen or atmosphere without the gas being measured).
(4) Start countdown after pressing “ON” again.
(5) After finishing countdown, the screen flickers to display the current concentration
that is measured.
(6) After zero calibration is finished, the screen flickers to display “OK” 3 times.
(7) Return to the measurement mode.
Note: For conventional gas, e.g. O
2
, H
2
S and CO, please make sure the
detector has been powered on for at least one hour before attempting a
zero calibration. For rare gas, e.g. ETO, methanol, methanal and VCM, it
needs to be 24 hours.
[M-02] -- Gain calibration
(1) Press “+” to select the menu item M-02.
(2) The screen displays span countdown time after pressing “ON” , Please refer to
table in M-04 for span time for different gases.
(3) Apply testing gas.
(4) Start countdown after pressing “ON” again.
(5) After finishing countdown, the screen flickers to display the current concentration
that is detected.
(6) After gain calibration is finished, the screen flickers to display “OK” 3 times and start
the subsequent down count.
(7) You can stop or continue apply testing gas during the countdown process.
(8) Return to measuring mode after finishing count down.
Note: For conventional gas, e.g. O
2
, H
2
S and CO, please make sure the
detector has been energized for at least one hour before attempting a gain
calibration. For rare gas, e.g. ETO, Methanol and VCM, it needs to be 24
hours.
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