Description
Application Scenarios
In a petrochemical refinery’s gas detection network, dozens of toxic and combustible gas transmitters are distributed across process units, tank farms, and loading terminals. Each transmitter outputs a standard 4-20 mA signal proportional to gas concentration, but the control room needs a centralized, reliable way to monitor all loops without running individual cables to separate controllers.
The 05704-A-0145 solves this by consolidating four detector loops onto a single card mounted in a System 57 rack. Each channel receives its 4-20 mA signal, provides isolated 24 V loop power to the field transmitter, and displays the reading on a front-panel backlit LCD . When a detector crosses an alarm threshold, the card’s front-panel LEDs indicate the alarm level, and relay outputs can trigger ventilation, shutoff valves, or notification systems. The card stores its configuration in EEPROM, so settings survive power cycles without reprogramming .
Parameter
| Main Parameters | Value / Description |
|---|---|
| Product Model | 05704-A-0145 |
| Manufacturer | Honeywell |
| Product Category | Four Channel Control Card / 4-20 mA Input Module |
| Input Channels | 4 independent, isolated 4-20 mA |
| Measurement Range | 0 to 25 mA (linear) |
| Supply Voltage | 18 to 32 VDC |
| Loop Powered Output | Isolated 24 V ±5%, 25 mA max |
| Maximum Loop Resistance | 500 Ω including sensor |
| Power Consumption | 7.5 W typical / 8.3 W maximum |
| Display | Backlit LCD, bar graph + digital |
| Alarm Indication | LEDs per channel: A1, A2, A3, Fault, Inhibit |
| Dimensions (H×W×D) | 132 × 25 × 172 mm |
| Weight | ~170 g |
| Operating Temperature | -5°C to +55°C |
| Configuration Storage | EEPROM |
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Isolated loop supply: Each channel provides its own isolated 24 V power, eliminating the need for external power supplies and preventing ground loops between transmitters.
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500 Ω loop resistance: Accommodates long cable runs and high-resistance field wiring while maintaining measurement accuracy.
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EEPROM configuration: Alarm setpoints, ranges, and channel parameters are retained without battery backup.
