Galil Motion Control

Our next two-day product school is Thursday February 6, 2014 through February 7, 2014. If you are new to Galil, sign-up now! The training will be at our headquarters in Rocklin, CA (near Sacramento).

Loss of an encoder can result in the motor running away unconditionally with brush DC motors or trapezoidal commutated brushless motors.  This is a dangerous situation in motion control systems.  With Galil sinusoidal brushless servo drives, encoder loss will not cause a runaway condition and it is possible to have an emergency controlled move to a safe position.

Galil’s recently released DMC-30000 Pocket Motion Controller Series offers higher performance, better power efficiency, smaller size, and a lower price than prior generation, single-axis controllers. A popular product in the series is the DMC-30012 which combines a single-axis motion controller and 800W brushed/brushless sine drive in a single, compact package. Now, Galil introduces another controller/drive package, the DMC-30017 which contains a 6A microstepping drive. Also available is the new DMC-31xxx option which features a 16-bit ADC and sinusoidal encoder input option.

This article discusses the basics of the options for using a BiSS encoder with a Galil motion controller or Pocket PLC.

The Galil BiSS interface is a standard upgrade option for the following controllers:

A majority of motion control systems that include feedback will use an incremental encoder. The draw back to incremental encoders is that upon power up the controller does not know the position of the motor in absolute terms. To compensate for this, system engineers will home a system upon power up by driving the motor to a switch at a known location.

The issue of wiring the hall sensors on brushless servo motors often arises here in the Galil Applications Department.

When running Galil motion controllers in standard dual loop mode, the PID motion control loop is split up between the load and the motor encoder. The Derivative (KD) loop is closed around the motor encoder. The Proportional (KP) and Integral (KI) loops are closed around the load encoder. The motor encoder is wired into the auxiliary encoder inputs, and the load encoder is wired into the main encoder inputs.