Installation manual

Danaher Motion Kollmorgen Appendix C
SERVOSTAR
®
S and SERVOSTAR
®
CD Series 115
MENCTYPE 4
Encoders with A and B channels only The simplest of encoders provide only
an A and B Channel. MENCTYPE 4 configures the SERVOSTAR for these
signals. These encoders provide no power-
up information about where the motor
is positioned, so this information is obtained through a special initialization
process known as 'wake and shake'. When using MENCTYPE 4, the process for
initialization is automatically triggered on power-up when the drive is enabled
or by using ENCSTART.
During the initialization process, "wake and shake," the SERVOSTAR puts
current through two phases of the motor causing the motor shaft to rotate into a
"torque detent." The magnets simply align the motor shaft to a position the
SERVOSTAR understands. The motor is then rotated to the next pole position
by energizing the windings in a slightly different manner. The SERVOSTAR
then has enough information to establish an appropriate commutation angle
using the number of motor poles (MPOLES) and the number of counts for the
encoder (MENCRES).
This method of initialization has the advantage of allowing an extremely cost-
effective feedback device. However, the requirement to pull the motor into these
torque detents is subject to outside influences (such as friction) and can prevent
the motor motion from occurring very effectively or even at all! Additionally,
large inertia loads can overshoot and oscillate during this pull-in position, giving
the microprocessor false readings. These MENCTYPEs are best for systems
with specific criteria requirements such as low friction, low cost, and low
inertial loads. The amount of electrical current used in this initialization mode is
adjustable using the IENCSTART variable and may need to be adjusted to
optimize performance for large inertial loads.
MENCTYPE 5
Not supported
MENCTYPE 6
Incremental with A/B and Hall Channels MENCTYPE 6
supports encoders as
described in MENCTYPE 0, but lacking the marker or index channel. This
device is selected using MENCTYPE 6 and follows the same process used in
MENCTYPE 0 with the exception of the final search for the marker pulse. The
system establishes the commutation angle based on the Hall effect edge.
MENCTYPE 6 is most commonly used with linear motors.