1771-AF1 | Allen Bradley | Fiber Optic Converter Module

Configured for high-distance signal propagation in PLC-5 networks, the Allen Bradley 1771-AF1 (1771-AF1 Fiber Optic Converter Module) provides direct physical and electrical execution of Data Highway Plus (DH+) and Remote I/O (RIO) protocol conversion over optical media.

Hardware Specifications

Profinet / EtherNet/IP Deterministic Networks

The 1771-AF1 module utilizes the 1771 I/O chassis backplane bus to interface with the controller, facilitating backplane bus communication velocity sufficient for the timing requirements of DH+ and RIO networks. The module executes signal conversion without introducing deterministic jitter, ensuring that remote node response times remain within established parameters. Firmware flash compatibility is achieved through the physical chassis connection, while I/O density scaling is managed by the network adapter's capability to bridge the converted optical segments. The dual port architecture allows for redundant loop configurations, providing a deterministic path for data packets across long-distance installations up to 30,000 ft.

Frequently Asked Questions

Q: Does the 1771-AF1 support hot-swapping within the I/O chassis?

A: The 1771-AF1 is designed for chassis mounting, but it is not recommended to hot-swap the module while the system is under load. Always de-energize the chassis before insertion or removal to prevent electrical arcing and damage to the backplane pins.

Q: How is the connector keying configured for this module?

A: The module features physical keying to prevent incorrect slot installation. The upper connector is keyed to 54-56, and the lower connector is keyed to 16-18. Ensure the chassis backplane keying matches these settings prior to installation.

Field Installation Guidelines

1. Mounting: Secure the module within a 1771 I/O chassis. Ensure the module is fully seated and the locking levers are engaged to maintain the integrity of the backplane bus connection.
2. Cable Termination: Use Belden 9463 or 1770-CD cable for the DH+/RIO port connections. Ensure the cable shield is properly terminated at the grounding point to prevent interference.
3. Fiber Integrity: Clean all fiber optic connectors using an industry-standard inspection tool before engagement. Ensure the bend radius of the fiber cabling exceeds the minimum specification to prevent signal attenuation.
4. Power Verification: Confirm that the 5 VDC power supply to the 1771 chassis is capable of supporting the 1.0 Ampere current load required by the module.
5. Environment: Install the module in a NEMA 12 rated enclosure to protect against dust and splashing water. Verify that ambient temperatures remain within the -25 to 70 deg C range.