30
Manual: NGP-300D
18. Nitrogen Analyzer Instructions
Component
Description
3 ½ Digit Display
The 3 ½ digit liquid crystal display (LCD) provides direct readout of nitrogen
concentrations in the range of 0 - 105.0% (100.1% - 105.0% used for calibration
determination purposes). The digits also display error codes and calibration codes as
necessary.
Low Battery Indicator
The low battery indicator is located at the top of the display and is only activated when the
voltage on the batteries is below a normal operating level.
% Symbol
The “%” sign is located to the right of the concentration number and is present during
normal operation.
Calibration Symbol
The calibration symbol is located at the bottom of the display and is timed to activate when
a calibration is necessary.
ON/OFF Key
This key is used to turn the device on or off.
Calibration Key
This key is used to calibrate the device. Holding the key for more than three seconds will
force the device to enter a calibration mode
Automatic Calibration
After the unit is turned on, it will automatically calibrate to room air. The display should be stable and reading 79.1%.
To check the nitrogen concentration of a sample gas: (after the unit has been calibrated)
1.
Connect the Tygon tubing to the bottom of the analyzer by threading the barbed adapter onto the oxygen sensor.
2.
Attach the other end of the sample hose to the sample gas source and initiate flow of the sample to the unit at a rate of
1-10 liters per minute.
2 liters per minute is recommended
.
3. Using the ON/OFF key, make sure the unit is in the power “ON” mode.
4.
Allow the nitrogen reading to stabilize. This will take approximately 30 seconds or more.
Calibrating the N
2
Analyzer
Calibrate the N
2
analyzer upon initial power-up. Thereafter, Maxtec® recommends calibration on a weekly basis. To serve as a
reminder, a one week timer is started with each new calibration. At the end of one week a reminder icon appears on the bottom
of the LCD. Calibration is recommended if the user is unsure when the last calibration procedure was performed, or if the
measurement value is in question.
With compressed air (79.1% N
2
), new calibration is required when:
• The measured N
2
percentage in 79.1% N
2
is above 80.1% N
2
• The measured N
2
percentage in 79.1% N
2
is below 78.1% N
2
• The CAL reminder icon is blinking at the bottom of the LCD
A simple calibration may be made with the sensor open to static ambient air.
Calibration Errors and Error Codes
The nitrogen purity analyzer has a self test feature built into the software to detect faulty calibrations, oxygen sensor failures, and
low operating voltage. Refer to the following table for an explanation of error codes and possible actions to take.
firealarmresources.com
