RAYTHEON MARINE GMBH 135-097 NG011 0312 SIGNAL UNIT NAUTO ALARM E00

1. Product Identification & Overview

• Manufacturer: Raytheon Marine GmbH (Note: This division is now part of HENSOLDT, a leading European sensor technology company).

• Model / Part Number: 135-097

• Order / Serial Identifier: NG011 0312

• Product Type: Signal Unit (Audible & Visual Alarm).

• Common Name: Nauto Alarm Unit, Bridge Alarm Indicator.

• Primary Function: A centralized, fail-safe audible and visual alarm annunciator for the ship’s navigation bridge. It is a critical component of the Watch Alarm System mandated by international safety conventions (SOLAS).

2. Technical Description & Function
The NG011 Signal Unit is a robust, standalone alarm panel designed to provide unmistakable audible and visual alerts to the officer on watch (OOW). Its core purpose is to ensure the OOW remains vigilant and responds to system status changes or timer-based warnings.

Key Operational Modes:

• NAUTO Alarm (Primary Function): Initiates a loud, distinctive audible alarm (buzzer/siren) and a bright flashing visual indicator (typically a red or amber light/beacon) when the ship’s autopilot is disengaged or deviates from its set course beyond a predefined limit. This alerts the OOW to immediately take manual control of the helm.

• Watch Alarm / Deadman Alarm: Functions as a periodic reminder system. The OOW must reset a timer (e.g., every 3, 6, or 12 minutes as set) to confirm alertness. Failure to reset the timer triggers the audible and visual alarm, summoning assistance.

• General Bridge Alarm: Can be integrated to annunciate alarms from other critical navigation systems (e.g., gyro failure, steering gear fault, navigational aid failure) depending on the vessel’s specific wiring configuration.

3. Typical Features & Specifications

• Housing: Durable, marine-grade metal or high-impact plastic casing designed for harsh saltwater environments (corrosion-resistant).

• Front Panel: Contains:

  • One or more prominent visual warning lights/rotating beacons (often red or amber).

  • A loud, penetrating audible sounder (buzzer or electronic siren).

  • A Mute/Silence button to acknowledge and quiet the audible alarm (the visual alarm typically continues until the fault condition is rectified).

  • A Reset/Test button to reset the watch timer, test the alarm function, or acknowledge an alarm condition.

• Mounting: Designed for fixed installation on the ship’s navigation bridge console or overhead panel for optimal visibility and audibility.

• Power Supply: Operates on standard shipboard DC voltage (commonly 24V DC). Includes protective circuitry against spikes and reverse polarity.

• Connections: Terminal strip or connector for power input and alarm signal inputs (typically dry contact closures from the autopilot, gyrocompass, or other alarm sources).

4. Purpose & Importance (Why it’s Essential)
This unit is a fundamental safety-critical device mandated under SOLAS Chapter V (Safety of Navigation). It directly addresses human factors by:

• Preventing Unattended Bridge: Ensuring an alert officer is always present.

• Preventing Course Deviation: Providing immediate warning of autopilot disengagement, preventing potential collisions or groundings.

• Providing System Status: Acting as a centralized, unambiguous alert point for key navigational faults.

5. Common Integration & Context
The NG011 Signal Unit is typically found interfaced with:

• Autopilot Systems (e.g., Raytheon/Anschütz, Sperry Marine).

• Gyrocompasses and Steering Control Systems.

• Integrated Bridge Systems (IBS) or Navigation Alarm Panels.