Overview
The Allen-Bradley 1756-ENBT is an EtherNet/IP bridge module for the ControlLogix series, engineered to provide high-speed Ethernet communication in chassis-based control systems. This module belongs to the 1756 series of ControlLogix Communication Modules and is designed to work as a bridge between two or more devices like a controller and an I/O module. The product was discontinued on December 31, 2021, with 1756-EN2T as its functional replacement. This used-condition module remains in high demand for retrofit and legacy system applications.
Key Features
- 10 to 100 Mbps Ethernet speed with auto-negotiating functions
- 64 TCP connections and 128 CIP connections, which can be used for any combination of connections on implicit applications
- Supports real-time I/O messaging, information exchange, and general messaging
- One Ethernet RJ45 Category 5 port for direct network integration
- Web-enabled module for remote configuration and diagnostics
- Single-slot design for compact chassis installation
Technical Specifications
- Current draw: 700 mA at 5.1 VDC; 3 mA at 24 VDC
- Power dissipation: 3.7 W; Thermal dissipation: 12.6 BTU/hour
- 30 Volt DC isolation from Ethernet network to backplane
- Operating temperature: 0 to 60°C; Relative humidity: 5 to 95%
- Ethernet: RJ45 Category 5 (shielded or unshielded cables supported)
- Open enclosure; installs in any slot in a 1756 chassis
- Weight: 0.44 lbs
Typical Applications
- Connecting ControlLogix processors to distributed I/O via Ethernet
- High-speed processor interlocking, control distributed I/O, and routing to devices on different NetLinx networks using Ethernet/IP as a backbone
- Inter-PLC communication and remote HMI access over industrial Ethernet
- Real-time data collection from multiple networked devices
- Legacy system integration where 10/100 Mbps is sufficient for throughput requirements
Compatibility & Replacements
The functional replacement for the discontinued 1756-ENBT is the 1756-EN2T, which offers higher speed and expanded features. The 1756-ENBT works with ControlLogix processors and supports Studio 5000 firmware configuration. The module meets the common industry protocol (CIP) for safety in data transmission, ensuring compatibility with standard EtherNet/IP networks. Verify firmware revision compatibility with your Studio 5000 environment before installation.
