Overview

The Digital Control and Monitoring Unit (DCMU) is the primary interface and control system for the CCR. It manages local and remote operation, brightness step selection, configuration settings, system monitoring, and fault and warning logging. The DCMU provides both control and diagnostic functionality.

Primary Functions

The DCMU receives operator commands from the local keypad or remote input. It controls brightness step selection. It sends regulation commands to the firing card and SSR. It monitors output current and system conditions. It detects and logs faults and warnings. It displays operational status on the screen. It acts as the control “brain” of the regulator.

Interface Functions

The DCMU includes the display screen, keypad buttons, configuration menu, diagnostics menu, fault and warning logs, and run-time log. It allows operators to switch between LOCAL and REMOTE mode, turn the CCR ON or OFF, access configuration settings (password protected), and review fault history.

Monitoring Capabilities

The DCMU monitors output current, fault conditions, warning conditions, operational status, and system runtime. If abnormal conditions are detected, the DCMU logs the event, displays warning or fault messages, and may disable output if required.

L-828 vs L-829

Both models include the DCMU. The L-829 model includes expanded monitoring capability compared to the L-828. Electrical regulation remains the same between models; monitoring functionality differs.

Interaction with Control Circuitry

The DCMU communicates with the firing card, SSR, input contactor, current transformers, and optional IRMS / Megger module. It coordinates the entire regulation and protection system.

Password Protection

Configuration changes require password entry. This prevents unauthorized modification of brightness step configuration, remote input voltage settings, calibration parameters, and advanced configuration settings.

Safety Consideration

The DCMU display and status indicators do not replace proper electrical verification. Before servicing, follow lockout/tagout procedures and verify de-energization with properly rated equipment.

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