6 Operations and Functions
6-4. External output operation
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6-4. External output operation
Signal Transmission System
Electric current transmission (non-isolated) 4 – 20 mA
Transmission Path
CVVS
Transmission Distance
CVVS 1.25 mm2(AWG16): Within 1.25km
CVVS 2.0 mm2(AWG14): Within 2.0km
Connection Load Resistance
Below 300
Ω
Mode
4 - 20 mA(output value)
1
Power Off
0 mA
2
Initial Clear
4 mA (Fixed)
3
Detection Mode(No alarm)
4 - 20 mA (concentration output)
4
Detection Mode(Gas alarm)
4 - 20 mA (concentration output)
5 Detection
Mode
(Full scale over)
20.5 mA (Fixed)
6
Out of operating temperature
range
4 - 20 mA (concentration output)
7
Fault Alarm
0.5 mA (Fixed)
8
INHIBIT
4 mA (Fixed)
9
Alarm Test Mode
Output ON setting: 4 - 20 mA (concentration output)
Output OFF setting: 4 mA
10
User Mode
4 - 20 mA (concentration output)
11
Maintenance Mode
4 mA (Fixed)
Example of Gas Concentration and External Output
4 - 20 mA specification
4 mA
20 mA
20.5 mA
Full scale over
20.5mA fixed output
Gas concentration
External output
0
Zero suppression
Detection Mode
User Mode
Maintenance Mode
(Standard:4mA fixed)
Full scale
20mA output
CAUTION
The 4 - 20 mA output is already adjusted. In case of over scale, an output will not exceed 20.5 mA.
Output during INHIBIT is based on 4 - 20 mA output setting in the maintenance mode.
(Standard:4.0mA)
In particular, when the detector is started or the specification is changed, be careful about 4-20 mA
output setting. Understand how the detector functions, and take actions, if necessary, so that the
signal receiver side can prepare to avoid false alarms.
