Position/Synchron Control Features; Load Encoder Gear Function - ABB ACSM1 Firmware Manual

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Position/synchron control features

Load encoder gear function

Positioning uses the measured speed and position of the load. The load encoder
gear function calculates the actual load position on the basis of the measured motor
shaft position.
Load encoder gear application examples:
Positioning uses the measured
speed and position of the load. If
no encoder is mounted on the load
side, the load encoder gear func-
tion must be applied in order to cal-
culate the actual load position on
the basis of the measured motor
shaft position.
A second encoder (encoder 2)
mounted on the load side is used
as the source for the actual posi-
tion value. (Note: Inverted gear ra-
tio is considered when the position
control output (speed reference) is
produced).
The load encoder gear parameters
GEAR DIV
Note: The sign of the programmed gear ratio has to match the sign of the
mechanical gear ratio.
Because the drive speed control uses motor speed, a gear function between position
control (load side) and speed control (motor side) is needed. This gear function is
formed from the motor gear function and inverted load gear function. The gear
function is applied to the position control output (speed reference) as follows:
Drive control and features
are set as follows:
60.03 LOAD GEAR MUL
60.04 LOAD GEAR DIV
71.07 GEAR RATIO MUL
71.08 GEAR RATIO DIV
M
3~
ENCODER 1 MOTOR
M
3~
60.03 LOAD GEAR MUL
Load speed
=
Encoder 1/2 speed
Motor speed
=
Load speed
GEAR LOAD
and 60.04 LOAD