NMEA multiplexer NDC-4

This Actisense™ NMEA Multiplexer / Combiner allows connection of up to five NMEA (National Marine Electronics Association) inputs, and multiplexes / combines them to its two NMEA outputs.

This approach offers these major advantages:

• Enables the vessel owner complete access to all NMEA data sources, instead of the standard one device
• Each NMEA input device is Opto-isolated from all other NMEA device in the system
• Significant reductions in installation cost (from reduced cable lengths and requiring only one NMEA cable to be routed around the bridge to supply the multiplexed NMEA data

The NDC-4 has two ISO-Drive outputs which are fully compatible with both NMEA 0183 and PC RS232 ports.

Electrical spike protection is provided as standard on all four input channels using opto-isolators. This protects any connected equipment from most system faults; a particularly valuable benefit as equipment requiring the most data, such as a PC or chart plotter, is often the most expensive to repair or replace.

The NDC-4 Data Multiplexer contains intelligent software that manages the multiplexing operation, allowing every input to have a chance of its data reaching the combined NMEA output. Tested up to and beyond a combined 400% loading of the four inputs.

With configuration software you can easily alter the operating mode between MULTIPLEXER or AUTOSWITCH modes.

AUTOSWITCH mode can be also pre-configured at factory by ordering it with NDC-4-ASW option. In autoswitch mode 4 identical inputs are  given priorities and always only the  input having the highest priority is allowed to pass its data to NMEA output.

Autoswitching is an essential feature when building redundant navigation systems.