Allen-Bradley 1786-TNCL10 ControlNet Coaxial Cable Assembly

Allen-Bradley 1786-TNCL10 ControlNet Coaxial Cable Assembly

The Allen-Bradley 1786-TNCL10, also cataloged as the 1786-TNCL10 Coaxial Cable Assembly, operates as a dedicated hardware component for deterministic 5 Mbps signal transmission within ControlNet media networks.

Hardware Specifications

Deterministic Backplane & Bus Communication Characteristics

ControlNet relies on a deterministic physical layer using Manchester encoding at 5 Mbps. Physical layer signaling integrity depends directly on strictly managed 75-Ohm transmission line impedance across all tap drops and backbone links. The 1786-TNCL10 assembly prevents standing wave reflections and high-frequency attenuation caused by mismatched field terminations. Quad-shielding layers maintain high signal-to-noise ratios across harsh high-noise industrial environments, preventing frame corruption and high-velocity firmware communication dropped packets on Allen-Bradley I/O backplane links.

Frequently Asked Questions

Q: What physical installation limits prevent impedance degradation on the 1786-TNCL10?

A: The minimum bend radius of 3.0 inches (76 mm) must be maintained at all times during installation. Bending the RG-6 coaxial assembly tighter than this limit deforms the internal dielectric core, altering the characteristic 75-Ohm impedance and inducing signal reflections.

Q: Can this cable assembly be modified or shortened in the field?

A: Modification or cutting of the assembly is strongly discouraged. The 1786-TNCL10 features factory-terminated, pressure-tested BNC connectors optimized for low attenuation. Field crimping alters the propagation delay and signal velocity characteristics required for deterministic ControlNet timing.

Field Installation Guidelines

• Tap Connection Interface: Connect BNC connectors directly to designated ControlNet media taps (such as 1786-TPS) using standard quarter-turn lock mechanisms without applying excessive torsional stress to the cable boot.
• Routing Requirements: Maintain physical separation of at least 12 inches (305 mm) from high-voltage AC lines, variable frequency drives (VFDs), and heavy motor leads to mitigate electromagnetic coupling.
• Cable Strain Relief: Secure the coaxial cable within 6 inches (152 mm) of termination points using non-crushing cable ties to avoid crushing the outer jacket and inner dielectric.