Page 4-2
Airnet II Particle Sensor Operations Manual
Chapter 4
4-20 mA Signal Configuration / Operation
4-20 mA Outputs
The instrument status signal is not controllable by the user. The two particle count
signals are channels 1 and 2.
Each channel is capable of driving a grounded load of 400 ohms or less. All grounds are
common and are common to the internal analog ground of the sensor.
The signals are output through a 6-pin Mini-Fit, Jr. connector plug located on the
sensor’s rear panel.
Table 4-1
Summary of 4-20 mA Channel Thresholds
First signal output
Channel 1 particle counts
Second signal output
Channel 2 particle counts
Third signal output
Instrument status
Table 4-2
4-20 mA Channel Thresholds
Channel
301
501
501A
510
510XR
1
0.3 µm
0.5 µm
0.5 µm
0.5 µm
0.5 µm
2
0.5 µm
5.0 µm
1.0 µm
5.0 µm
5.0 µm
Table 4-3
4-20 mA Factory Preset Status Levels
Current
Flow Status
Laser Status
8 mA
OK
OK
12 mA
OK
Bad
16 mA
Bad
OK
20 mA
Bad
Bad
