Originally Posted by
Bry195
this makes sense as to how it came about.
how much torque does it take to keep a motor spinning at a constant speed with no load?
I know you arent an advocate for the 6 amp method and neither am I. 6 amps at 8 volts and a resistance of x =allot of watts. if the torque required to maintain a speed is lower than the demand then where is something like 48 watts going? is there a significant amount of this 48 watts being converted to mechanical power? is this procedure is used (6 amp method) and it happens to coincide with peak efficiency of the motor how will it affect using it on track? what if it lands on peak power or lands on a terrible efficiency zone?
6 amps below 10k is almost all heat. there isnt a significant connection between the 48 watts being consumed and the power coming out because there is no torque. 6 amps works because it is directly tied to heat and has nothing to do with adjusting the power out. This wasnt an attempt to make it appear you believe in the 6 amp method. You can continue to disagree and claim you know better but can you debunk my explanation about heat? My point isnt that you can only have a max of 6 amps waste heat but since the number was generated on track over time its waste heat plus the waste of a motor running through efficiency curves on track.
A steady-state no-load current draw of 6A is ~48W of pure heat (and some noise), since it's doing no mechanical work. By definition, since it's not accelerating, there's no net torque, so the only torque being generated is overcoming internal resistances.
Obviously it's going to draw more under load and while accelerating. The real questions are, how much more, and how much of that is mechanical work? A single no-load current value won't tell you that. To answer that, you need a proper dyno, or alternatively cut some laps and compare lap times vs temperature.
Using a reference no-load current value is only useful if someone else has done the work to figure out an optimal setting for the particular motor you're using, and you're just trying to replicate their setting.