Complete the following voltage drop calculation LEN=32 Backbone Length= 26 Cable Type= Mid. The result is:

Complete the following voltage drop calculation LEN=32 Backbone Length= 26 Cable Type= Mid. The result is:

• A. 1.25 Volts
• B. 0.75 Volts
• C. 2.5 Volts
• D. 0.5 Volts

Answer: (A)

Voltage drop on a NMEA 2000 trunk is determined by the amount of current flowing and the total resistance of the path from the power source to the farthest device along the backbone. The backbone length and the chosen cable type set how much resistance that path has. Mid cable type represents a middle-ground resistance for the conductors, so using a longer path with this cable adds a predictable amount of drop. With LEN of 32 and a backbone length of 26, the network’s calculator uses those values together with the Mid cable’s resistance to estimate how much voltage is lost along the trunk under worst‑case conditions. That calculation gives a drop of 1.25 V, meaning the farthest device would see about the supply minus 1.25 V. This is why 1.25 V is the correct result for these inputs. If you imagine making the run shorter or choosing a lighter gauge (lower resistance) cable, the drop would be smaller; using a heavier gauge or a longer LEN would increase the drop. The other numbers would imply different overall resistance or current scenarios that aren’t produced by these exact inputs.

Voltage drop on a NMEA 2000 trunk is determined by the amount of current flowing and the total resistance of the path from the power source to the farthest device along the backbone. The backbone length and the chosen cable type set how much resistance that path has. Mid cable type represents a middle-ground resistance for the conductors, so using a longer path with this cable adds a predictable amount of drop.

With LEN of 32 and a backbone length of 26, the network’s calculator uses those values together with the Mid cable’s resistance to estimate how much voltage is lost along the trunk under worst‑case conditions. That calculation gives a drop of 1.25 V, meaning the farthest device would see about the supply minus 1.25 V. This is why 1.25 V is the correct result for these inputs.

If you imagine making the run shorter or choosing a lighter gauge (lower resistance) cable, the drop would be smaller; using a heavier gauge or a longer LEN would increase the drop. The other numbers would imply different overall resistance or current scenarios that aren’t produced by these exact inputs.