The 1794-IH16 FLEX I/O module from Allen‑Bradley provides sixteen digital input points. Each point operates on 125 Volts DC power. This module suits high‑voltage industrial sensing applications. Engineers use it to monitor discrete field devices like limit switches. The unit carries North American Hazardous Location approval. This certification guarantees safe operation in dangerous environments. It works perfectly with demanding process and factory automation systems.
Reliable High‑Voltage Input Performance
The 1794-IH16 reads voltage signals between 90 and 146 Volts DC. Its nominal on‑state voltage rating sits at 125 Volts DC. The module requires a minimum on‑state current of 1 mA. It draws a nominal 2 mA at the rated 125 Volts DC. Maximum on‑state current reaches 3 mA. The off‑state voltage threshold stays below 20 Volts DC. Off‑state current must not exceed 0.8 mA. These precise electrical thresholds ensure reliable signal discrimination.
The module dissipates up to 6 Watts of power at 146 Volts DC. Its thermal dissipation equals 20.47 BTU per hour at the same voltage. This low heat output simplifies enclosure design. Engineers can place it in dense control panels without excessive cooling. The non‑isolated input design works well for common‑reference voltage sensing systems.
Flexible System Integration
The 1794-IH16 integrates seamlessly into the FLEX I/O architecture. It mounts on several compatible terminal bases. Popular choices include the 1794‑TB3, 1794‑TB3S, 1794‑TB3K, and 1794‑TB3SK bases. The 1794‑TB3 base provides 52 screw‑clamp terminals. It supports daisy‑chaining for efficient power distribution. The module slides onto a standard DIN rail for quick installation.
Installation follows a straightforward mechanical process. Hook the terminal base over the top of the DIN rail. Slide the base tight against the adjacent adapter module. Push the base down until it locks securely onto the rail. These steps create a solid mechanical and electrical connection every time.
Expert Application Guide for Engineers
The 1794-IH16 solves key pain points for automation engineers. It accepts standard 125V DC control voltages directly. This compatibility eliminates the need for external signal converters. The 16‑input density packs significant I/O into a compact footprint. Installed dimensions measure just 3.7 x 3.7 x 2.7 inches. Engineers save valuable panel space with this design.
The module requires a 1794 series adapter for communication. It connects via the FlexBus backplane interface. The 1794‑TB3 base draws 640 mA at 5 Volts DC from the backplane. This low current draw leaves ample power for other modules. Procurement managers appreciate the wide compatibility with existing systems. The module works with all major 1794 analog and digital I/O modules.
Logistics & Standard Packaging Details
