Description
The SM Electrics A067.74 is the centralized mtBUS controller for the A067 Engine Order Telegraph (EOT) system. It serves as the core intelligence unit for managing and monitoring the communication between various bridge, engine control room (ECR), and engine room (ER) telegraph stations on a vessel.
Product Overview
- Manufacturer: sm electrics GmbH (Germany)
- Model Number: A067.74
- Product Type: mtBUS Controller / Centralized EOT Processor
- Application: Marine propulsion remote control and EOT systems.
- Mounting: Designed for standard DIN-rail (TS35) installation.
Key Functionality
- Network Management: Permanently manages and monitors all connected mtBUS network units, including bridge telegraph levers, wing control units, and ECR repeaters.
- System Diagnostics: Features an integrated 4-line, 20-character LC display that provides real-time system status and diagnostic information to maintenance and service personnel.
- Interface Signaling: Provides essential dry relay contacts for ship-wide safety systems:
- Wrong-way Contacts: Triggers an alarm if the commanded maneuver (e.g., Ahead) does not match the actual propulsion direction (shaft or pitch).
- EOT Call Contact: Activates audible/visual alarms if maneuver commands between connected stations do not match.
- Failure Contact: Sends an alarm signal to the Integrated Alarm, Monitoring, and Control System (IAMCS) or Bridge Alert Management (BAM) if an abnormal system situation is detected.
- VDR Interface: Includes an RS485 serial interface for connection to Voyage Data Recorders (VDR/S-VDR) according to IEC 61162-2.
Technical Specifications
- System Voltage: 24V DC (Nominal)
- Power Consumption: 2–3W
- Interface Technology: RS485 bi-directional mtBus
- Environmental Protection: Designed to meet IEC 60945 standards for maritime equipment.
Operational Context
The A067 system is often called the “Electrical Shaft,” as it links multiple bridge stations to operate synchronously. The A067.74 controller acts as the central hub, ensuring that maneuver commands—transferred by human-machine interface (HMI) levers—are reliably delivered to the propulsion remote control system or, in backup scenarios, to the engine room’s local station.
Maintenance Note: As this unit is the central controller for the entire EOT network, it is critical to ensure that its firmware matches the requirements of your specific vessel’s telegraph layout. Before replacement, verify the network topology and ensure all peripheral devices are properly addressed on the mtBUS loop.
