Technical Specification

General:

• Product Type: Watch Alarm Extension Buzzer / Alarm Panel (part of a BNWAS – Bridge Navigational Watch Alarm System)
• Part Number (P/N): Often associated with 770318.1598 (as seen in some listings).
• Compliance: Likely complies with IMO Resolution MSC.128(75) and IEC 62616 (standards for BNWAS), and IEC 60945 (marine navigational equipment – general requirements).
• MED Type Approved: As a critical safety component, it is highly probable to be MED (Marine Equipment Directive) type approved with a Wheel Mark.

Electrical:

• Power Supply: 24 VDC (nominal)
  • Operating Voltage Range: Typically 19.2 VDC to 28.8 VDC (or similar range for marine 24V systems).
• Current Consumption: Low, likely in the range of milliamps (e.g., < 100 mA typical, but specific value would need precise documentation).
• Connection: Terminal blocks for power and alarm input/output.

Performance:

• Audible Alarm (Buzzer):
  • Sound Level: Typically 80 dB(A) or 85 dB(A) at 1 meter, depending on the specific model and its intended location.
  • Sound Characteristics: May offer multiple sound characteristics or types of buzzer tones.
• Visual Indication: Likely includes a visual alert (e.g., flashing LED or light) to accompany the audible alarm.
• Alarm Stages: Operates as a Stage 2 or Stage 3 alarm panel within a BNWAS, meaning it activates after initial bridge alarms if unacknowledged.
• Remote Alarm Transfer: Receives alarm signals from a main BNWAS control unit.

Physical & Environmental:

• Dimensions: Specific dimensions would vary, but typically compact for flush mounting. For similar SM-Electrics panels, a common cut-out is 68x92mm, and dimensions around 72x96x75mm (WxHxD).
• Mounting: Designed for flush mounting into a panel or bulkhead.
• Material: Robust, marine-grade casing (e.g., plastic or metal) suitable for interior shipboard use.
• Ingress Protection (IP) Rating:
  • Front Panel: Typically IP23 (for indoor, flush-mounted) or potentially higher (e.g., IP65 if it’s more exposed).
  • Rear/Terminals: Lower IP rating as it’s typically enclosed.
• Operating Temperature: Standard marine operating temperature range (e.g., -15°C to +55°C).
• Storage Temperature: Standard marine storage temperature range (e.g., -25°C to +70°C).

Interface:

• Input: Receives alarm signals (likely dry contact or specific voltage signal) from the main BNWAS unit.
• Output: Primarily audible and visual alarm. No direct NMEA or other complex outputs expected from this specific “extension buzzer” type of panel.