ACR Ocean Signal 741S-02037 - AIS Alarm Box
Description
Immediate AIS Distress Alerts
The AIS Alarm Box monitors NMEA data from a compatible AIS receiver. When the receiver detects an AIS MOB or AIS SART transmission, the box sounds an 87 dB alarm and provides a visual warning.
This provides a dedicated alert that does not rely solely on someone watching the vessel’s navigation display. It is particularly useful aboard vessels where crew members may be below deck, working away from the helm, or unable to hear the chartplotter’s internal alarm.
Selectable Target Monitoring
The alarm can be configured to respond to all compatible AIS MOB and AIS SART signals within receiving range. It can also store up to 30 individual MMSI numbers, allowing operators to prioritize alarms from personal AIS beacons assigned to their own crew.
Separate audible tones identify whether the received transmission comes from an AIS man-overboard device or an AIS search-and-rescue transponder. This helps the crew understand the type of alert without first consulting another display.
NMEA 0183 Integration
The unit accepts NMEA 0183-HS AIS data at 38,400 baud and includes an NMEA through-port. This allows it to be added to a compatible AIS installation without preventing the AIS data from continuing to another navigation device.
Configuration is completed through a USB connection using Ocean Signal software available for supported Windows, macOS, and Android devices. Settings include monitored MMSI numbers, alarm behavior, volume, and relay operation.
External Alarm and Engine Control
An integrated relay output can activate compatible external equipment when an alert is received. Depending on the vessel’s installation and configuration, this may include a louder external alarm or an engine kill circuit intended to reduce separation from a person overboard.
Any connection to an engine shutdown system should be designed and installed by a qualified marine technician.
Flexible Marine Installation
The compact enclosure can be panel-mounted or installed with its mounting bracket. Its waterproof construction also permits installation in exposed locations where the crew can easily see and hear the alarm.
The alarm requires a compatible AIS receiver and does not receive AIS radio transmissions by itself. It should be installed where its warning indicators and controls remain accessible during an emergency.
Technical Specifications
Power
- Supply voltage: 10.8–15.6 V DC
Dimensions
- Dimensions: 9.0 × 7.2 × 7.2 cm / 3.54 × 2.83 × 2.83 in.
- Panel cutout diameter: 57 mm / 2.25 in.
Durability
- Operating temperature: -15°C to 55°C / 5°F to 131°F
- Waterproofing: Waterproof to a depth of 1 m / 3.3 ft.
- Installation environments: Interior or exterior marine mounting
Included
- Ocean Signal AIS Alarm Box
- Mounting bracket
- DC power cable
- USB configuration cable
- Installation hardware
- Product documentation
Additional
- Product type: AIS MOB and AIS SART alarm
- Manufacturer: Ocean Signal
- Part number: 741S-02037
- Audible alarm output: 87 dB at 1 m
- Detected devices: AIS MOB beacons and AIS SARTs
- Stored MMSI numbers: Up to 30
- Alarm modes: All compatible AIS targets or selected MMSI numbers
- Alert identification: Separate tones for AIS MOB and AIS SART signals
- Mounting options: Panel or bracket mounting
- Compatible related devices: Ocean Signal rescueME MOB1 and PLB3
- Warranty: 2 years against manufacturing defects
Interfaces
- AIS data input: NMEA 0183-HS
- Input baud rate: 38,400 baud
- Supported AIS data sentence: !VDM
- Data output: NMEA 0183-HS through-port
- Configuration interface: USB
- Alarm relay contacts: 2 × 8 A at 250 V AC
Documentation:
