The maximum voltage drop for an NMEA 2000 network powered from the battery is:

• A. 0.5 Volts
• B. 2.0 Volts
• C. 1.17 Volts
• D. 0.25 Volts

Answer: (C)

In NMEA 2000, the power backbone has a specified maximum voltage drop from the battery to any node. This limit ensures that every device on the network still sees a voltage within its operating range even under worst‑case loading and with the resistance of the backbone and branch wires.

The value represented by this limit is about 1.17 volts. That means, from the battery to the farthest device, the total drop along the trunk and spurs should not exceed roughly 1.17 V. This keeps node voltages high enough for reliable operation even when several devices are drawing current and the wiring length and gauge add up in resistance.

Choosing a much smaller drop like 0.5 or 0.25 V would be overly conservative for typical installations and could be hard to meet in longer runs. A larger drop like 2.0 V would risk devices seeing too low a voltage and potentially malfunctioning, especially at the farthest points.