The Rockwell/Allen-Bradley 1794-TB3 is a FLEX I/O Terminal Base Unit that serves as a wiring termination point for distributed I/O installations within Allen-Bradley FLEX I/O systems. The unit features 16 I/O terminals with 3-wire cage clamp connections and accommodates a total of 52 terminals—18 common terminals and 18 supply terminals (+V). Operating at 24V DC/AC or 120V DC/AC with maximum supply voltage of 125V AC/DC, the TB3 supports current capacity up to 10 A per terminal. DIN rail mounted in a compact 94 mm × 94 mm × 69 mm form factor, it accepts solid or stranded copper wire from 0.34 mm² to 4 mm² (22 AWG to 12 AWG) with terminal screw torque of 0.56–0.79 Nm.
Technical Specifications
• Model: 1794-TB3
• Termination Type: 3-wire cage clamp
• I/O Terminals: 16
• Total Terminals: 52 (18 common, 18 supply)
• Maximum Current: 10 A per terminal
• Supply Voltage: 125V AC/DC, 50/60 Hz maximum; 24V DC/AC or 120V DC/AC operational
• Isolation Voltage: 125V continuous; module-dependent ratings up to 60V AC or 75V DC
• Backplane & FlexBus Current: 640 mA @ 5V DC each
• Wire Size: 0.34–4 mm² (22–12 AWG); solid or stranded copper, 75°C rated
• Terminal Torque: 0.56–0.79 Nm (5–7 lb-in)
• Dimensions: 94 × 94 × 69 mm (3.7 × 3.7 × 2.7 in)
• Weight: ~0.249 kg (0.5 lbs)
• Mount: DIN rail
• Enclosure: IP20 open-style
– Key Features
• Cage clamp termination simplifies wiring and maintenance
• Supports multiple FLEX I/O module types: digital, analog, temperature, and specialty I/O
• Operating temperature range: −20°C to 70°C (−4°F to 158°F)
• Storage temperature: −40°C to 85°C
• Rated for 30G shock and 5G vibration (10–500 Hz)
• UL, cULus, CE, and RoHS certified
– Compatibility & Integration
The TB3 integrates with FLEX I/O modules including 1794-IA8, 1794-OA8, 1794-IB8, 1794-OB8, 1794-IB16D, 1794-IT8, 1794-IRT8, 1794-IR8, 1794-IF4I, and 1794-OF4I. Network communication supported through Remote I/O, DeviceNet, ControlNet, and EtherNet/IP via appropriate adapter modules.
