[Kevin Sevcik]

I suggest you look closer at your feedback and command values. I'm nearly certain that while you're commanding a positive speed, you're getting a negative speed feedback. Or vice versa. This would explain your run away condition. If a positive Voltage output doesn't give you a positive feedback, then your PID loop will make things worse and worse and worse until it's running as fast as possible in the opposite direction.

Your solution is to either swap your A and B channels on the encoder, or the wires on the M+ and M- terminals. Do either one of those (not both!) and things should start working better. I believe our programming team is using P=0.5, I=0.0005, and D=0 and is getting decent results. Once they had the feedback and command directions matching, that is.