I am using a Gecko 340 with an 1800 line encoder. Becuase of the Gecko 250khz max, I can only get 2,080RPM from the 4,000RPM motor.
It apparently boils down to how fast the drive can take in encoder pulses.
So, what is the max encoder pulse speed the Viper can digest?
The viper can take up to a 625Khz encoder signal. It converts to 4X (quadrature) in the chip.
Manufacturer of CNC routers and Viper Servo Drives
www.LarkenCNC.com and www.Viperservo.com