1746-IB8 Allen-Bradley SLC 500 Digital DC Input Module
Product Introduction
The 1746-IB8 module belongs to the trusted SLC 500 series by Allen-Bradley. It provides eight sinking input channels rated for 24V DC operation. You can use this I/O module in both non-hazardous and hazardous areas with Class 1, Division 2, Groups A, B, C, or D ratings. Its compact design saves space while delivering stable DC input performance for industrial control systems.
Technical Specifications of the 1746-IB8
The Allen-Bradley 1746-IB8 supports a wide voltage range from 10 to 30V DC (nominal 24V DC). Each input operates as a sinking type. The module draws only 50 mA from the 5V DC backplane and 0.0 mA from the 24V DC backplane.
Signal delay is consistent at 8 milliseconds for both ON and OFF transitions. The off-state current stays below 1 mA, and the off-state voltage does not exceed 5V DC. Nominal input current at 24V DC is 8 mA.
Power dissipation per point is 0.27W, while total module heat dissipation reaches 1.3W (equivalent to 4.4 BTU/hr). Dielectric withstand voltage is 1500V AC, and isolation between backplane and inputs is also rated at 1500V AC. Communication circuits are tested at 500V.
Additionally, the 1746-IB8 works with I/O connections 1746-HT and 1746-HCA. Its step response is 100 ms in and 2.5 ms out.
Mechanical and Environmental Ratings
The 1746-IB8 operates reliably between 0°C and 60°C (32°F to 140°F). It handles non-condensing humidity from 5% to 95%. Vibration tolerance reaches 2.5G at 57–500 Hz, and shock resistance is rated at 30G.
Furthermore, this module meets UL and CE certifications. It also complies with NEMA standard ICS 2-230 for noise immunity.
Installation Guidelines for the 1746-IB8
First, ensure the chassis power is off before inserting the 1746-IB8 into any SLC 500 chassis slot. Align the module with the card guides and press firmly until latched. Next, connect field devices to the input terminals using appropriate wire gauges. Use 1746-HT or 1746-HCA wiring arms for easier termination. Finally, label each input clearly for maintenance.
Do not remove or insert the module while power is applied. Also, avoid exposing the module to moisture beyond the specified range.
Packaging List
1 x 1746-IB8 Allen‑Bradley SLC 500 DC input module
1 x 1746-HT or 1746-HCA wiring arm (depending on shipment)
1 x user manual (printed quick guide)
Note: No certificates or warranty documents are included in this package.
Shipping & Delivery
We ship all orders via FedEx, UPS, or DHL. Tracking numbers are provided within 24 hours after dispatch.
Frequently Asked Questions (FAQ)
1. Can the 1746-IB8 be used in hazardous locations?
Yes, the 1746-IB8 is approved for Class 1, Division 2, Groups A, B, C, and D hazardous industrial locations.
2. What is the maximum signal delay for the 1746-IB8?
The signal delay is 8 milliseconds for both turning ON and OFF. This ensures stable input reading in most automation systems.
3. Does the 1746-IB8 work with 12V DC sensors?
Yes, the module accepts input voltages from 10 to 30V DC, so 12V DC sensors operate correctly within this range.
4. How much current does the 1746-IB8 draw from the backplane?
It draws only 50 mA from the 5V DC backplane and 0 mA from the 24V DC backplane, making it very efficient.
5. What wiring accessories are compatible with the 1746-IB8?
Use either 1746-HT or 1746-HCA terminal arms for easy field wiring connections to the 1746-IB8 module.
