WhatsApp:+86 18150087953 WeChat: +86 18150087953 
Email：
Description
Technical Specifications
| Parameter Name | Value |
|---|---|
| Product Model | 1746‑IB8 |
| Manufacturer | Allen‑Bradley / Rockwell Automation |
| Product Type | Digital DC Sinking Input Module |
| Series | SLC 500 |
| Number of Inputs | 8 sinking inputs |
| Points per Common | 8 |
| Voltage Category | 24V DC |
| Operating Voltage Range | 10…30V DC |
| Nominal Input Current | 8 mA @ 24V DC |
| Off‑State Voltage (Max) | 5.0V DC |
| Off‑State Current (Max) | 1 mA |
| Signal On Delay (Max) | 8 ms |
| Signal Off Delay (Max) | 8 ms |
| Backplane Current (5V DC) | 50 mA |
| Backplane Current (24V DC) | 0 mA |
| Thermal Dissipation (Max) | 1.90 W |
| Isolation Voltage | 1500V AC (optical) |
| Operating Temperature | 0 to 60°C |
| Storage Temperature | -40 to 85°C |
| Backplane Connector | 16‑pin male |
Main Features and Advantages
Optical Isolation and Noise Immunity: The 1746‑IB8 incorporates optical coupling between the field inputs and the system backplane, providing 1500V AC isolation -11. This feature protects the controller from voltage spikes and electrical noise commonly found in industrial environments. The 1746‑IB8 also includes filter circuitry that provides signal noise reduction, ensuring reliable input detection even in electrically noisy environments -7.
Sinking Input Configuration: The 1746‑IB8 provides eight sinking DC input channels, meaning the module receives (sinks) current from sourcing (PNP) field devices -2-5. This is the most common configuration for DC input modules in many regions and is compatible with a wide range of standard industrial sensors and switches. The 1746‑IB8 simplifies system design by providing a single common for all eight inputs -1-4.
Fast and Predictable Response: With a maximum signal delay of 8ms for both on‑to‑off and off‑to‑on transitions, the 1746‑IB8 delivers consistent and predictable performance for most discrete control applications -1-2. This response time is suitable for monitoring pushbutton inputs, limit switches, and other common field devices that do not require ultra‑fast response times.
Compact and Chassis‑Integrated Design: As a standard SLC 500 module, the 1746‑IB8 installs directly into the SLC 500 chassis, requiring no additional enclosure or mounting hardware. The 1746‑IB8 is designed to integrate seamlessly into existing SLC 500 systems, with color‑coded terminals on some versions facilitating accurate field wiring -7. The 1746‑IB8 features a simple interface with clear labeling for each input, simplifying installation and maintenance -12.
Application Field
Discrete Manufacturing and Assembly: The 1746‑IB8 is widely used in discrete manufacturing applications, including automotive assembly, packaging machinery, and material handling systems. It monitors digital sensors for product presence, position detection, and machine status. In conveyor systems, the 1746‑IB8 interfaces with photoelectric sensors and proximity switches to track product movement and verify part positioning.
Process Industries: In continuous process environments such as chemical plants and water/wastewater treatment facilities, the 1746‑IB8 monitors limit switches on valves and actuators, as well as level switches in tanks and vessels. The 1746‑IB8 provides reliable signal acquisition from field devices located in control rooms or in field‑mounted cabinets, with its optical isolation protecting against noise from motor starters and other inductive loads.
Machine Building and OEM Equipment: Machine builders and original equipment manufacturers frequently integrate the 1746‑IB8 into SLC 500‑based control systems for industrial machinery. The 1746‑IB8 provides the necessary input monitoring for safety interlocks, operator pushbuttons, and machine cycle status. Its wide operating voltage range of 10‑30V DC ensures compatibility with various sensor types, making the 1746‑IB8 a versatile choice for custom machine designs.
