AMC 1ACOs, Инструкция по эксплуатации

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AMC-1ACOs One Channel CO Monitor with DSI
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2 S1 Provides a voltage representation of the gas concentration reported on channel 1
Measure between GND (TP4) and S1 (TP2)
Range: Minimum 0.4V
No target (0 ppm) gas measured, 4 mA on 4-20 mA input
Range: Maximum 2V
High gas concentration measured, 20 ma on 4-20 mA input
4 GND Reference ground, used with VFD (TP1), S1 (TP2) and S2 (TP3)
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On Site Calibration Equipment Required

Digital multi-meter with a minimum display range of 0 to 10.0 VDC.

Miniature screwdriver or trimmer adjustment tool.

Calibration adapter, available from AMC

Zero and Span gases (Contact AMC for information)
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Calibration Procedure
5.2.2.2.1
On Board Sensors
Calibration of the gas sensor involves two steps. First the “zero” must be set and then the
“span” must be calibrated.
Note:
The calibration procedure will cause false alarms and or fail signal. Appropriate
precautions may be required.
Refer to the Figure 10 for DSI Layout, to perform the following calibration procedure:
1. Open the front cover on the AMC-1ACOs enclosure.
2. Attach the multi-meter as shown in Figure 12.

Connect negative (black) lead to TP22 (main board)

Connect positive (red) lead to TP4 (main board)

To set the zero and span specifically the measurements must be taken on the
DSI board by connecting negative (black) lead to TP4 (GND) and connecting
positive (red) lead to TP2 (S1)

Refer to Section 5.2.1.2 for trip threshold adjustment
3. Apply a Zero gas sample, 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 Zero trimmer VR5 (DSI board) for a reading of 0.4 V +/-
5mV.
5. Apply the Span gas sample, 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. Since the output range is 0.4 to 2.0 V, a full-scale concentration should
register 2.0 V after a 2 minute exposure. Proportionately, a half-scale
concentration of gas should register 1.2 V, and so on.
V span adjust = ((Gas used / Full scale) x 1.6VDC) + 0.4 VDC.
6. At 2 minutes adjust the Span trimmer VR3 (DSI board) for the appropriate the
Span voltage reading.