Model IR400
35
9.3.4 Analog Current Output
The following table shows the values of the analog output when in certain modes or fault
conditions.
Condition Type
Non-HART Units
HART Units
HART Override
Mode*
Start Up, Fault
0 mA
1.25 mA
3.5 mA
Zero, Gas Check or Cal
1.5 mA
1.5 mA
3.5 mA
Dirty Optics
2.0 mA
2.0 mA
3.5 mA
0-100% LEL
4 – 20 mA
4 – 20 mA
4 – 20 mA
Over-range
21.7 mA
21.7 mA
21.7 mA
Table 6: Analog Current Output
*
HART units can be configured to never output current less than 3.5 mA if the host equipment
is incapable of working below this level.
9.3.5 Recommended Cable Lengths
Power
– The maximum distance between the IR400 and the power source varies according to
the wire size. Maximum cable resistance = V drop / I device = 4.0 V / 0.20 A = 20
Ω
, where V
drop = V supply – V device and V supply =+24 VDC.
AWG
Stranded Cable (
Ω
/1000 ft)
Feet
Meters
12
1.71
5800
1700
14
2.73
3600
1100
16
4.35
2200
700
18
6.92
1400
440
20
10.9
910
270
Table 7: Maximum Distance between IR400 and Power Source
Analog Output Signal
– The maximum total distance between the IR400 and a device with a
500-Ohm input impedance varies according to the wire size.
AWG
Stranded Cable (
Ω
/1000 ft)
Feet
Meters
14 2.525
9000 2740
16
4.016
5200
1585
18 6.385
3800 1160
20
10.15
2400
730
Table 8: Maximum Distance between IR400 and 500-Ohm Input Impedance
Summary of Contents for IR400
Page 2: ......
Page 15: ...Model IR400 11 Figure 5b IR400 Mounting Dimensions with a European Box ...
Page 20: ...Model IR400 16 Figure 7 Wiring Diagram from IR400 to Control Equipment ...
Page 41: ...Model IR400 37 9 6 Engineering Documentation ...
Page 45: ...Model IR400 HART Field Device Specification for Point IR Gas Detector ...
Page 78: ...Model IR400 Infrared Point Detector for Hydrocarbon Gas Applications Modbus programming guide ...