@stan2004 posted:IMy question is are you measuring the RPM on a test-stand (rollers) so that you aren't trying to target the tach laser on a moving train? Or are you dis-engaging the motor from the transmission/gears so as to measure the no-load RPM characteristics as might be found on a motor datasheet?
You pegged it.
To be clear, this isn’t a real problem I am trying to solve so much as a personal academic interest.
I intend to disconnect the motor to get a “no-load” reading. Then a load reading on rollers. And finally a live reading on the track.
The cheap Tachs come with reflective strips. My thought is to put a strip on the armature of a disconnected motor for no load baseline and then a strip on a wheel on rollers for load baseline. And last the wheel on track with just the engine, and maybe incrementally with cars added.
So for $20 its worth a whirl.
