User Manual

Table Of Contents
Sinusoidal Commutation
Advanced Digital Motor Controller User Manual 109
FIGURE 8-16. Encoder Sinusoidal configuration
Or by sending the configuration command:
^BFBK ch mode
Where mode:
0: Encoder
1: Hall
2: Hall+Encoder
3: SSI sensor
4: Sin/Cos Sensor
5: Resolver
Each mode requires a various amount of additional setup and/or calibration as described in
the following sections.
Incremental Encoder-Only
A quadrature encoder can be used to determine the rotor position. Enter the Encoder PPR
using the PC Utility.
FIGURE 8-17. Encoder PPR configuration
Or by sending the configuration command:
^EPPR channel nn
Optimally, the encoder should have a PPR that is at least 128 x the number of pole pairs.
For example a motor with 4 pole pairs should have a 128 x 4 = 512 Pulse per revolution.
This will result in 2048 counts for a full turn of the rotor, and therefore the electrical angle
to be measured with 360 / 2048 * 4 = 0.7 degrees, resulting in a very smooth changing
sinusoidal drive to the motor. A significantly lower resolution encoder will results in a step-
ping sinusoid. A higher resolution encoder will not improve the waveform.