Description
The Liaaen Helitron DC-0018A is a specialized Supervisor PCB Card used in legacy Liaaen/Helitron propulsion control systems. Liaaen (later integrated into Rolls-Royce Marine and now part of the Kongsberg Maritime ecosystem) is renowned for Controllable Pitch Propeller (CPP) systems and associated maneuvering control electronics.
The DC-0018A serves as a monitoring and watchdog module. Its primary function is to supervise the integrity of the control signals, power supply status, and communication health between the bridge control levers and the pitch control actuators at the propulsion unit.
Key Technical Specifications
| Parameter | Value/Description |
| Model | DC-0018A |
| Component Type | Supervisor/Watchdog Control Card |
| System Compatibility | Liaaen Helitron Propulsion Control Systems |
| Function | Signal monitoring, fault detection, and fail-safe logic |
| Inputs | Feedback from pitch actuators, bridge command signals |
| Operating Voltage | 24V DC |
| Mounting | Control cabinet rack mount |
| Environment | Marine-grade (vibration and humidity resistant) |
Implementation & Maintenance
This supervisor card is a critical safety component. It is designed to trigger a “System Alarm” or place the propulsion system into a “Follow-up” or “Emergency” mode if it detects a discrepancy between the bridge command and the actual propeller pitch.
- Replacement Note: As this is a legacy system, replace the card only after verifying that the fault is not due to a loose connection on the backplane (rack). Corrosion on the card edge connectors is a frequent cause of “false” supervisor alarms in these older systems.
- Safety Interlocks: Because this module monitors critical propulsion safety, any replacement must be followed by a dockside sea-trial test. You must verify that the “Watchdog” circuit effectively triggers an alarm when a command signal is intentionally disconnected.
Critical Advice: Before installing a new DC-0018A, check your system’s “I/O Mapping List” (found in the original vessel control drawings). Some versions of the DC-0018A are hard-wired for specific propulsion segments (Port, Starboard, or Bow Thruster). Ensure the DIP switches or jumpers on the new board are set to match the specific “Node Address” or “Segment ID” of the old board to avoid system-wide communication conflicts.
