Amps Draw and Voltage Drop Question 2

BFL13 wrote:
If the furnace draws 8 amps and there is a 0.2v drop when it is on ...

To properly measure voltage drop you need measure between the connection at the motor and the positive post on the battery.

But, another way to look at it is how many amps are drawn from the battery.

If smaller gauge wire, instead of the vast majority of the amps turning the motor some are turned into HEAT by the resistance in the wire.

So, the answer really depends on how you phrase the question.

Bottom line is you want to maximize the amps taken out of the battery that are turned into RPM by the motor, not wasted in the wire.

Will draw slightly MORE current due to less voltage drop, results in motor spinning a bit faster.

RV furnace motor is a DC motor, DC for practical intents can be considered like a resistor since you are not dealing with impedance/inductance like you do with AC devices.

If you want the furnace motor to draw less current, you would need to REDUCE the voltage going to the motor. However, that results in less RPMs for the fan which results in less air flow which results in possibility of overheating the furnace and/or creating a fire hazard..