Subelement N: N – Marine— Topic 89: NMEA Data
Question 3-89N5
Element 3 (GROL)An NMEA 2000 system with devices in a single location may be powered using this method:
Explanation
NMEA 2000 networks are designed to supply DC power to connected devices directly through the network's backbone cable. For a small system with devices located in a single, confined area, the total current draw is typically low, and the overall length of the backbone is short. In this scenario, injecting 12V DC power at one end of the backbone cable, creating an "end-powered network," is sufficient and prevents significant voltage drop across the network.
Dual mid-powered networks are generally used for larger systems with higher current draws or longer backbone lengths to minimize voltage drop. Individually powering each device negates a key advantage of NMEA 2000, which is simplified wiring through integrated power and data lines. Finally, NMEA 2000 devices absolutely require 12 volts DC (typically 9-16V) to operate, so stating no power is needed is incorrect.
Related Questions
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