Overview

Certain CCR models equipped with digital monitoring support RS485 serial communication using the Modbus RTU protocol. This communication method allows integration with airport lighting control systems, PLC systems, SCADA platforms, and remote monitoring systems. RS485 provides reliable communication over longer distances than Ethernet in certain installations.

RS485 serial connectivity requires a Communications Card to be installed on the Digital Control & Monitoring Unit upon ordering the CCR. The RS485 connection allows for communication using ModbusRTU.

Protocol

The CCR supports Modbus RTU over RS485. Modbus RTU is a serial communication protocol commonly used in industrial control systems.

Typical Functions Available

When properly configured, RS485 communication may allow remote ON/OFF control, brightness step selection, status monitoring, fault and warning monitoring, and retrieval of runtime data. Available functions depend on system configuration.

Physical Connection

RS485 communication uses twisted pair wiring and differential signaling (A and B terminals). Shielded cable is recommended. Proper polarity must be maintained. Incorrect polarity may prevent communication.

Addressing

Each CCR must be assigned a unique Modbus address. Duplicate addresses on the same RS485 network will cause communication failure.

Configuration

Network configuration may require setting Modbus address, baud rate, parity, and stop bits. Settings must match the master control system.

Operational Mode

For remote control over RS485, the CCR must be in Remote mode. External system must send valid Modbus commands. Local mode disables remote step control.

Common Communication Issues

If RS485 communication fails, verify correct wiring polarity. Confirm proper baud rate and parity. Check unique device address. Inspect cable shielding and grounding. Verify CCR is not in Local mode.


Airport Lighting Company | Type L-828, Type L-829 Ferroresonant Constant Current Regulator