Omron CJ1W-NC271 - 12-2009, Руководство по эксплуатации

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DEVIATION COUNTER RESET
Section 10-10
10-10 DEVIATION COUNTER RESET
10-10-1 Overview of DEVIATION COUNTER RESET
The deviation counter can be reset during position control for PCUs with unit
version 1.3 or later.
The deviation counter reset function resets to 0 the position deviation accu-
mulating in the Servo Drive’s position loop deviation counter during position
control. When pressing using torque control, when the machine catches and
stops moving, or in other cases when the command present position and the
feedback present position vary greatly, the positioning operation may not fin-
ished because the position deviation never becomes less than the completion
width. DEVIATION COUNTER RESET can be used in such cases to reset the
accumulated position deviation to 0 and thus complete the positioning opera-
tion.
With this function, the PCU’s deviation counter reset function uses a move-
ment command in the direction opposite to and the same size as the accumu-
lated position deviation so that the command present position will match the
feedback present position.
DEVIATION COUNTER RESET is valid only during position control after the
servo has been locked and will be ignored if executed during speed control or
torque control, or when the servo is unlocked.
Note Execute the PCU’s DEVIATION COUNTER RESET only while the motor axis
(machine) is stopped, by being pressed against something for example. This
function executes a movement command in the direction opposite to and of
the same size as the accumulated position deviation, so the machine may be
subjected to shock if a movement command in the opposite direction is sud-
denly executed for a rotating axis. Also, do not execute DEVIATION
COUNTER RESET for a vertical axis that is stopped by a servo lock only,
without being held mechanically. While the vertical axis is servo-locked, the
axis is controlled so that the vertical position is held using the accumulated
position deviation. Therefore, executing a deviation counter reset may cause
the motor load to fall.
Position
Target position in pressing direction
(position command value)
Pressing stop position
Solid line: Command present position
Dotted line: Feedback present position
(actual motor position)
Time
Speed
Target speed in pressing direction
(speed command value)
Dotted line: Actual motor speed
Solid line: Command speed
Time
Command proportional to position
deviation executed.
Position deviation
Start
Pressing
DEVIATION COUNTER RESET
Time