775 pro performance and break in

[Doug G]

We too had some issues with our 775Pro motors and the versaplanetaries... Everything needs to be just right to get the free current down to 10 Amps or less. We are running dual vertical axis shooter, 3:1 with our VPs and dual 3.5 inch Colsons per axis. We had to really crank down on the clamp for the motor shaft to keep it from spinning.

[cmwilson13]

free current was somewhere around 1 to 1.5 if i remember right

[R.C.]

We are not using the VP's, using GT2 3mm belts and its fairly quiet with great performance atm. Also using press fit pulleys so no slippage!

[rahilm]

We're using 775pros with VersaPlaneteries in multiple places with no problem really (3:1, 30:1, and 100:1). The 3:1 goes into a 1:1.2 driving 4" AndyMark Stealth Wheels. At about 7k RPM (at the wheels), we're seeing about 10A current draw, which is right in line with the spec sheet. It gets pretty hot after 10 minutes of continuous usage, but that is completely reasonable. I can check with our students, but I don't think they did anything particularly special when putting together the planeteries.

[Ether]

Originally Posted by cmwilson13

free current was somewhere around 1 to 1.5 if i remember right

You probably have a lot more friction in your shooter setup than you realize.

40 amps @ 11.5 volts is 460 watts going into the motor, roughly 190 of which are being turned into heat.