Allen-Bradley 1786-RG6 ControlNet Quad-Shielded Coaxial Cable

Allen-Bradley 1786-RG6 ControlNet Quad-Shielded Coaxial Cable

Configured for high-speed deterministic data transfer in ControlNet communication links, the Allen-Bradley 1786-RG6 (1786-RG6 Quad-Shielded RG-6 Coaxial Cable) provides direct physical/electrical execution. It operates as the fundamental physical medium connecting network taps, network access points, and terminating resistors across distributed programmable logic controller (PLC) and remote I/O architectures.

Hardware Specifications

Industrial Control & Network Transport

The 1786-RG6 physical layer ensures deterministic backplane bus communication velocity and robust data frame integrity over extended distances. Featuring a quad-shielded construction consisting of dual foil layers and high-density braiding, the media delivers high electromagnetic interference (EMI) and radio frequency interference (RFI) rejection. This attenuation performance maintains strict EtherNet/IP and ControlNet deterministic protocol timing without frame drops, even when routed through high-noise industrial environments adjacent to variable frequency drives and high-voltage motor control centers.

Frequently Asked Questions

Q: What is the maximum segment distance supported when using the 1786-RG6 coaxial cable without repeaters?

A: A single ControlNet trunk line segment utilizing 1786-RG6 cable supports a maximum length of up to 1000 m (3280 ft) at 5 Mbps, depending on the total number of non-intrusive taps (1786-TPS) installed on the segment.

Q: Why is a precise 75 Ohm impedance matching critical for 1786-RG6 terminations?

A: Impedance mismatches create signal reflections along the high-speed data path. To prevent signal degradation and timing jitter, both ends of the 1786-RG6 trunk segment must be terminated with 75 Ohm terminating resistors (1786-XT).

Q: What are the strict bending radius limitations during physical installation in cable trays?

A: The minimum static bend radius for the 1786-RG6 cable is 25.4 mm (1.0 in). Bending the cable beyond this limit can deform the foam polyethylene dielectric, altering the characteristic impedance and causing signal distortion.

Field Installation Guidelines

1. Trunk Line Topology & Tap Connection: Route the 1786-RG6 cable as a continuous trunk line. Connect each node via a 1786-TPS tap. Ensure both physical ends of the trunk segment are terminated with 1786-XT 75 Ohm BNC terminators.
2. Shield Grounding & Isolation: Earth the coaxial shield at one single point per segment to avoid ground loops. Maintain proper electrical isolation throughout the rest of the cable run.
3. Conduit Separation & Cable Tray Routing: Maintain a minimum clearance of 300 mm (12 in) from high-voltage AC power lines, motor leads, and heavy inductive loads to minimize noise coupling.
4. Connector Termination Standards: Use specialized RG-6 crimp tools and BNC connectors compliant with Allen-Bradley specifications. Ensure a clean cut without disturbing the 18 AWG solid copper center conductor or damaging the quad-shield foil and braid layers.