Recalibration - AMC 210 Series Instructions Manual

AMC-210 Transmitter with external electrochemical sensor

5.2.3 RECALIBRATION

For full recalibration adjustments, follow the Set-Up procedure steps 1 to 9 inclusive. There are
two adjustments to be made for periodic recalibration: Zero and Span.
Zero: With the sensor in Zero Gas, the transmitter output signal current should read 4 mA.
This is obtained by adjusting the Zero trimmer on the transmitter for a voltage of
0.000 VDC at the test points in Figure 6. It is possible, under certain conditions that
the Zero current will fall below 4 mA.
Span: While the sensor is exposed to the calibration gas sample, adjust the Span trimmer on
the transmitter to set the transmitter output signal current proportional to the applied
gas concentration.
FIGURE 6: Calibration/Verification Set-up
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