Vfd Calibration - AMC 1ACOs Instructions Manual

AMC-1ACOs One Channel CO Monitor with DSI
7. Make sure alarm indicators (see Figure 1, item 1) turn on when meter reading
passes the WARNING and/or ALARM thresholds.
8. Let sensor recover in air.

VFD Calibration

5.2.2.2.2
A VFD adjust trimpot is provided for each channel, this allows for independent scaling of the
VFD output for different gas concentrations.
An example of this unique usage would be to provide the fullscale, 20 mA output current at the
channel output ie. 100PPM, then have the VFD output adjusted to full scale (10V) on a partial
channel scale ie 50PPM.
Refer to Figure 10 for DSI Layout to perform the following calibration procedure:
1. Open the front cover on the AMC-1ACOs enclosure.
2. Measurements are taken on the DSI board by connecting negative (black) lead to
TP4 (GND) and connecting positive (red) lead to TP1 (VFD).
3. Apply the desired gas concentration, with a calibration adapter cup firmly and
completely over the sensor on the AMC-DSI for 2 minutes with a flow rate of .5
liters per minute.
4. At 2 minutes adjust the VFD trimmer VR1 (DSI board) for the appropriate VFD
voltage reading. Full scale is 10V.
5. Make sure VFD activates appropriately for given voltage.
6. Let sensor recover in air.
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