AMC 1ACOs, Инструкция по эксплуатации

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AMC-1ACOs One Channel CO Monitor with DSI
23
TP22
RV6
RV5
TP5
TP6
JB8
JB10
1
NOTE: THE DSI BOARD IS REMOVED
GND
TP4
FIGURE 11: AMC-1ACOs Test Points and Trimpots.

Equipment Required

Digital multimeter with a minimum display range of 0 to 10.0 VDC.

Miniature screwdriver or trimmer adjustment tool.

Trip Threshold Adjustment
The formula below is used to determine the voltages the thresholds are adjusted to with the
trimpots.
V
alarm
= ((C
alarm
/ C
full scale
* I
Range
) + I
base
) * R
termination
* K
Gas Monitor 1A
Where

V
alarm
– The voltage measured at the alarm test point while adjusting the alarm
trimpot.

C
alarm
- The target gas concentration for the alarm

C
full scale
- The gas concentration corresponding to full scale (20 mA)

I
Range
– Calibrated on DSI, typically 16 mA for full range.
o
I
Range
+ I
base
typically add to 20 mA.

I
base
– fixed at 4.0 mA

R
termination
– fixed internally on Gas Monitor at 250 ohms

K
Gas Monitor 1A
– constant which describes the scaling used within the Gas Monitor,
fixed at 0.4