Eagle GD-1000, Техническое справочное руководство

Страница: 9 / 19

4-20mA ANALOG INPUT (GAS SENSOR INPUT) CALIBRATION USING A GAS
IMPORTANT: The gas sensor should be calibrated to the meter using the gas calibration
procedure on this page.
The gas sensor calibration allows one to calibrate the gas sensor input using air (zero ppm or mg/L)
and a calibration gas, which is within the gas sensor range.
•
Connect a gas sensor apparatus that connects to the calibration plug (figure A) that will
permit a 0ppm (mg/L) and a calibration gas of known concentration to be passed over the
sensor.
•
Enter calibration mode from the main operating display by pressing any push button, MNU,
CAL, enter password (default 0000), and then SNS.
•
Select channel one or two (do not select the mA option).The active gas sensor input will be
displayed, see “SNS CHx” display image above. The value displayed is in ppm & mg/l (both
are equivalent).
•
Apply a zero ppm (mg/L), concentration to the sensor and allow sufficient time for the display
to stabilize. The display may not settle to a zero ppm (mg/L)reading.
•
Press the ZRO push button to store the zero reference. This value is not adjustable to any
non-zero value
•
Apply a known ppm (mg/l) concentration gas to the sensor and allow sufficient time for the
display to stabilize.
•
Press the SPAN push button to select the SPAN adjustment mode (see CHx ADJ screen
above).
•
Set the correct gas concentration value by using the INC and DEC push buttons.
•
Press the ENT to accept the new span value, and the display will again display the active gas
concentration value.
•
To permanently store calibration, press the ENT push button. Press ESC to restore the
original calibration.
•
The user is returned to the “CAL GAS SENSOR” menu. Select the other channel or press
ESC until the main screen is displayed.
Notes:
••••
Be sure to store the calibration plug in a safe place so another calibration can be carried out
at a later time (figure A).
••••
The sensor should be calibrated at least twice a year.
••••
The sensor life expectancy is two years when exposed to air (see the GAS SENSOR
SPECIFICATIONS FROM THE MANUFACTURER section).
Figure A