Product Description
The Allen Bradley/Rockwell Automation 1791D-8B8P is a compact CompactBlock I/O module with an integrated power supply and DeviceNet adapter, offering 8 sinking inputs and 8 sourcing outputs. Its small size allows for placement near sensors or actuators in tight spaces, reducing wiring costs. It accepts a wide range of DC power (10-30V) and features NEMA Type 1+ input compatibility. It supports communication up to 500 Kbps over 100 meters, with short-circuit output protection and automatic baud rate detection. It can connect to master PLCs, SLCs, or SoftLogix Controllers as a slave device. Requiring no additional power supply or adapter (except for the 24V DC I/O supply), it offers polled, cyclic, and change-of-state communication modes. It mounts vertically or horizontally on DIN rails or panels, operating between 0-60C, and requires 14-gauge stranded wire with at least 3.64 inches of insulation for connections.
Is Your Device Showing These Signs?
The Allen Bradley 1791D-8B8P I/O block commonly experiences communication failures due to corrupted backplane connections or firmware incompatibility. Field wiring issues such as short circuits or open circuits in the sensor/actuator wiring directly connected to the I/O points cause module faults. Power supply fluctuations or inadequate grounding lead to erratic behavior and require immediate attention. Internal component failures within the module, specifically the power supply or communication ICs, necessitate component-level repair or module replacement. Addressing these issues restores optimal performance and prevents system downtime.
Technical specifications
The Allen Bradley 1791D-8B8P is a compact CompactBlock I/O module with a built-in power supply and DeviceNet adapter. It features 8 sinking inputs and 8 sourcing outputs, designed for space-saving installation near sensors/actuators. It supports a wide DC power range, NEMA Type 1+ inputs, and DeviceNet communication up to 500 Kbps. It acts as a slave device to master PLCs and offers various communication modes. Installation is simplified by the integrated power supply and adapter, and it can be mounted in multiple orientations.
Our Repair Process for the
1791D-8B8P
Our repair process for the Allen Bradley 1791D-8B8P I/O block begins with a thorough inspection of the backplane connections to eliminate corruption as a source of communication failure, followed by a verification of firmware compatibility and an update if needed. Next, we meticulously examine all field wiring for short circuits or open circuits that cause module faults, correcting any identified issues. Power supply stability and grounding adequacy are then verified and rectified to eliminate erratic behavior. If these steps do not resolve the issue, internal component failures are investigated, and component-level repairs are performed, or the module is replaced to restore optimal performance.
Your Guarantee: Warranty & Lifetime Support
Your satisfaction is our top priority, and we confidently stand behind the quality of our repairs. That's why every repair service is covered by our comprehensive 24-month warranty. Furthermore, we offer lifetime phone support – if you have questions or need assistance related to our repair down the road, we're here to help. Our service commitment is straightforward: we guarantee our work, and if you're not satisfied, we will make it right. Learn More about our Repair process.
Comprehensive Repairs You Can Depend On
We take immense pride in the quality and reliability of our work. Our process goes beyond simply fixing the immediate problem. We perform a comprehensive inspection of your main board (or other equipment) and proactively replace components known to be failure-prone or showing signs of potential future failure. Before any item is returned, it undergoes rigorous functional testing to ensure it meets performance specifications and operates flawlessly. Visit our main Repair Services page to learn more.
Save Significantly
Our primary goal is to save you hundreds, or even thousands, of dollars compared to the cost of new equipment replacement. By repairing existing components, we provide an economical solution that is also eco-friendly. At Roc Industrial, our commitment to integrity and community drives our consistent growth and ensures you receive a reliable, cost-effective solution.
Please Note: Roc Industrial operates as an independent service provider and is not an authorized distributor for the manufacturers or brands mentioned. Consequently, the original manufacturer's warranty is not applicable to items repaired or sold by us. Roc Industrial provides its own 2-year warranty on all repair services performed.