I am normally pretty good with dc voltage, but am a little confused as to why a voltage increase would also increase amperage? I get the 'pressure' of voltage but 13.8 was kitchen reading and 14.4 alternator.
The reason is that in a DC motor speed is proportional to voltage. More voltage then faster speed in a DC motor (with a constant field strength).
As I showed above, the faster the speed the required hp goes up a lot in a fan application.
A lot of folks make the mistake of using ohhm's law when it comes to electric motors. That can really mess them up. Without a complete dissertation, a motor is a torque matching device so it will draw whatever current is required to match the load requirement. An electric starter in a car is a series field DC motor and it does not behave as any other electric motor - trying to understand it using ohms law is fruitless...........
And running a 24 dc motor at 12 volts will run just fine but at half speed and half the rated hp.
