Explanation: NMEA 2000 networks operate on 12V DC. To guarantee reliable communication and operation for all connected devices, the NMEA 2000 standard defines specific limits for voltage drop across the network cabling. A maximum voltage drop of 1.5 volts from the power source to the furthest device on the network is specified. This ensures that even devices at the end of the longest segment receive at least 9 volts (assuming a 10.5V minimum from the 12V power supply, minus 1.5V drop), which is typically the minimum operating voltage for NMEA 2000 compliant devices. Exceeding this drop, as with 2.0V or 3.0V, could cause devices to malfunction or drop offline due to insufficient power. A 0.5V drop, while very low, is not the specified maximum limit and would impose unnecessary cabling constraints.