MSA DF-8500, User Manual

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DF-8500 Gas Detector
4 Operation
The device is factory-calibrated and delivered ready for installation. First
calibration is required after installation.
4.1 Startup
The device conducts self-checking during it starts up and sets the operating current
as output signal (default: 4.0mA), then displays below information:
Display testing
After power on, all segments on the display light, LED indicators are turned
on one by one as the sequence: green->red->red- >yellow, and after all the
LED indicators light, the green LED starts to flicker.
Software version
Displays the firmware version.
Sensor type
Displays the configuration information from different types of sensors, such
as CO, H
2
S, etc.
Measuring range
Displays the preset range of the gas sensor. 1000 stands for 1000 μ mol/mol,
and so on.
Alarm operation value
The display shows the preset alarm value. E.g. 100 and 300 stands for 100 μ
mol/mol and 300 μ mol/mol respectively.
Countdown
The screen displays the countdown of sensor’s stability.
Normal operation
After countdown, the screen displays the gas conce ntration.
Note: 1μmol/mol = 1ppm
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