Technical Specifications
| Parameter Name | Value |
|---|---|
| Product Model | Allen‑Bradley 1797‑BIC |
| Manufacturer | Rockwell Automation / Allen‑Bradley |
| Product Type | FLEX Ex Bus Isolator Module |
| I/O Module Capacity | Up to 8 FLEX Ex modules on slave side |
| Isolation Type | Galvanic isolation to DIN EN 60079‑11 |
| IS Module Classification | [Ex ib] IIC |
| Power Supply Voltage | 18‑32V DC @ 0.15 A (normal 24V DC) |
| Power Dissipation | 2.1 W |
| Thermal Dissipation | 7.2 BTU/hr |
| Max Input Voltage (Um) | 253V AC |
| Conductor Wire Size | 4 mm² (12 AWG) stranded max |
| Operating Temperature | ‑20 to 70°C (‑4 to 158°F) |
| Storage Temperature | ‑40 to 85°C (‑40 to 185°F) |
| Relative Humidity | 5‑95% non‑condensing |
| Operating Shock | Tested 30g peak, 11ms pulse |
| Vibration | 5g @ 10‑500Hz |
| Protection Factor | IP20 (must be installed in enclosure) |
| Weight | Approximately 200g (0.44 lbs) |
| Mounting | DIN Rail (35 x 7.5mm) |
| Torque for Terminals | 0.8‑1.0 Nm (7‑9 lb‑in) |
| Cable for Connection | 1794‑CE1 or 1794‑CE3 (max 1m/3.28ft) |
| Indicators | Green LED for power status |
| Agency Certification | CE, c‑UL‑us, CENELEC [EEx ib] IIC |
Main Features and Advantages
Galvanic Isolation for Intrinsically Safe Systems
The Allen‑Bradley 1797‑BIC provides galvanic isolation between the non‑intrinsically safe backplane bus and the intrinsically safe FLEX Ex backplane bus, effectively separating two sections of the I/O backplane while allowing IS and non‑IS field‑device wiring to coexist within the same I/O group . This isolation capability is fundamental for facilities requiring explosion protection, as the 1797‑BIC converts hazardous power to IS‑safe power to run the slave‑side bus receiver/transmitter circuitry and FLEX Ex backplane modules . The module’s galvanic isolation meets the stringent requirements of DIN EN 60079‑11, ensuring that a fault on the non‑IS side does not compromise the intrinsic safety of the field wiring connected to the FLEX Ex modules .
Flexible System Architecture with Mixed I/O Support
The 1797‑BIC enables a highly flexible and cost‑effective system architecture by allowing FLEX Ex modules and standard FLEX I/O modules to be configured on the same DIN rail, attached to the same adapter, and grouped together with appropriate sides of the bus isolator . This intermixed capability is a significant advantage for facilities with both hazardous and non‑hazardous areas, as a single 1797‑BIC can serve as the bridge between the two zones, eliminating the need for separate control systems or expensive intrinsic safety barriers for each field device. The module supports up to eight FLEX Ex modules on the slave side, providing substantial I/O capacity for hazardous area instrumentation .
