Purchase now: Allen Bradley 1747-ACN15 ControlNet Adapter
Purchase now: Atlantechdrives provides you the 1747-ACN15, a highly resilient ControlNet Adapter Module designed by Allen Bradley for the SLC 500 automation platform. As control systems scale across large manufacturing plants, centralizing all I/O cards in a single cabinet becomes physically impossible. The 1747-ACN15 serves as a remote I/O adapter, allowing an entire 1746 expansion chassis to act as a distributed slave node on a high-speed ControlNet network. Instead of processing logic locally, this module gathers field sensor data, transmits it deterministically over coaxial media to a master scanner (such as a ControlLogix PAC or an SLC processor with a 1747-SCNR), and receives output commands to actuate local valves and motors. It is the perfect migration tool for extending the life of your legacy SLC hardware while upgrading to a deterministic, high-bandwidth network.
Technical Specifications of the 1747-ACN15
The 1747-ACN15 occupies the processor slot (Slot 0) of a remote 1746 chassis. It operates at a fixed network speed of 5 Mbps and requires RSNetWorx for ControlNet to schedule its data connections.
- Part Number: 1747-ACN15
- Module Type: ControlNet Adapter Module
- Compatible System: Allen Bradley SLC 500 (1746 Chassis)
- Network Topology: ControlNet (RG-6 Coaxial)
- Network Speed: 5 Mbps
- Redundancy: Non-redundant (Single BNC connector)
- Maximum I/O Capacity: Up to 3 chassis (30 slots total)
- Backplane Current Draw: 900 mA at 5V DC
Expert Tips: MAC ID Configuration and Scheduling
Proper node addressing is the foundation of a stable ControlNet network. Expert Tip: Unlike modern Ethernet devices that use IP addresses, the 1747-ACN15 relies on a ControlNet MAC ID (node address) ranging from 1 to 99. This address is set using two physical rotary decimal switches located on the front of the module. You must configure these switches before applying power to the chassis; the module only reads the switch positions during its boot sequence. Furthermore, once the hardware is physically connected, the module will not automatically start controlling I/O. You must use RSNetWorx for ControlNet software to «schedule» the network, which calculates the Network Update Time (NUT) and allocates guaranteed bandwidth for the adapter.
Maintenance and Coaxial Wiring Rules
ControlNet is a high-frequency RF network that demands strict adherence to physical wiring rules. The 1747-ACN15 connects to the network trunk line using a BNC tap (like the 1786-TPR). Maintenance Warning: Never splice a ControlNet coaxial cable using standard electrical methods, and never leave an open tap on the network. The trunk line must be perfectly terminated with exactly two 75-ohm terminating resistors at the extreme physical ends of the cable run. If an operator bumps the cabinet and dislodges the BNC connector, the module will instantly drop off the network, turning off all associated outputs to maintain machine safety.
Frequently Asked Questions (FAQs)
Q: What is the difference between the 1747-ACN15 and the 1747-ACNR15?
A: The 1747-ACN15 features a single BNC port for standard, non-redundant media. The 1747-ACNR15 features dual BNC ports (Channel A and Channel B) for fully redundant media architectures, ensuring communication continues even if one cable is cut.
Q: Can the 1747-ACN15 execute ladder logic?
A: No. It is strictly a communication adapter. It contains no user memory and relies entirely on the remote master processor to evaluate logic and issue commands.
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To bridge existing ControlNet field devices to a modern ControlLogix rack, use this adapter alongside a 1756-CN2 bridge module.
