The 1794-TB3 is a Flex I/O component that is manufactured by Allen-Bradley. This component is specifically a Terminal Base unit, primarily used as termination points of field devices and power supply devices. this module is also used to host Flex I/O modules specifically, 1794-IA8, 1794-IA8I, 1794-IA16, 1794-OA8, 1794-OA8I, 1794-OA16, 1794-IB8, 1794-IB16XT, 1794-IB10XOB6, 1794-IB10XOB6XT, 1794-IC16, 1794-IG16, 1794-IH16, 1794-IV16, 1794-OB8, 1794-OB8EP, 1794-OB8EPXT, 1794-OB16, 1794-OB16D, 1794-OB16P, 1794-OB16PXT, 1794-OC16, 1794-OG16, 1794-OV16, 1794-OV16P, 1794-OW8, and 1794-OW8XT. The 1794-TB3 is had Three (3) terminal strips. The top terminal strip is composed of Sixteen (16) terminals designated for wiring of input and output signals. The middle and bottom terminal is composed of Eighteen (18) terminals, designated for common and voltage terminals. -V Common is located at Terminals B-16 and B-33; +V (Voltage In) Terminals is located at C-34 and C-5 terminals. For daisy-chaining to nearby Flex I/O module and terminal base, the daisy-chaining terminal is located at C-34 (+) and B-16 (-) for supply in and C-51 (+) and B-33 (-) for supply out. The 1794-TB3 has screw clamp terminals. To install the terminal base, position the terminal base at a slightly angled orientation. Hook the terminal base over the top of the DIN rail to attach the back of the terminal base to the DIN rail. The Terminal base hook must slide under the edge of the adapter module and the FlexBus connecter is engaged. Slide the terminal base and push tight against the adjacent adapter. To lock the terminal base to the DIN Rail, push the terminal base until the 1794-TB3 aligns and engages to the DIN rail.

The 1794-TB3 Flex I/O Terminal Base Unit by Allen-Bradley is a device which provides terminal connection points for I/O wiring and contributes to the formation of the backplane. It has a maximum of 16 I/O connections with 18 common terminals and 18 voltage terminals. The 1794-TB3 is used in an application with a 125V AC/DC electrical rating and it has a maximum current capacity of 10A with 0.21 x 1.3 mm2 (24-16 AWG) stranded copper wire intended for use with input and output modules. The 1794-TB3 has a Flexbus rating of 5V DC at 640mA and it supplies a 2A current to the I/O terminals. It also has V/COM Terminals ratings of 125V DC/AC and 10A at 50-60Hz. The 1794-TB3 provides voltage isolation of 125V (continuous) using Basic Insulation Type between Field Wiring Terminals to FLEXBUS and it has a terminal screw torque of 0.56 x 0.79 Nm (5 x 7lb-in). It has a T4A (North America) designated temperature code and an IEC T4 temperature code. The 1794-TB3 has an IEC-rated operational temperature of -20-70 deg. C (-4-158 deg. F) at 5-95% non-condensing relative humidity and it is tested and rated to withstand an operational shock of 30G and a vibration of 5G at 10-500Hz. The 1794-TB3 is c-UL-us, UL, CSA, and CE-certified and has a dimension 94mm x 94mm x 69mm (3.7in x 3.7in x 2.7in).