Rockwell Automation Motion Analyzer Software User Manual
Page 101
Rockwell Automation Publication MOTION-UM004B-EN-P - October 2012
101
Sizing Your System
Chapter 2
Table 59 - Carriage Cut Off Parameters
Parameter
Description
Load
(label 1 in
Figure 81
)
Mass of Carriage
Total mass of the linear moving parts.
Drive Roll Diameter
Diameter of the roll, driven from the motor.
Friction Coefficient
Coefficient of friction of the sliding bearing.
Cut Time
Time the carriage must be synchronized accurately with the material.
Critical Preferences
(1)
(label 2 in
Figure 81
)
Max Average Line Speed
Select this option for data entry when the maximum design speed of the constant-speed sections of the line is known. This
speed does not refer to the peak velocity of the feeder section, which is determined by Motion Analyzer software.
Min Cut length at
Max line speed
When you select the option to enter data based on Max Average Line Speed, this data is required. This is
the critical condition on which the sizing process is performed. To cut shorter lengths than this critical
length, the line speed must be reduced.
Cuts/min
Select this option for data entry when the number of cuts made by the system per minute is known.
Max Cut length at
Cuts/min
When you select the option to enter data based on Cuts/min, this data is required. This is the critical
condition on which the sizing process is performed. To cut longer lengths than this critical length, the
line speed must be reduced.
System Properties
(label 3 in
Figure 81
)
Settling Time
This is the time required for the system to achieve the required position accuracy before the cut commences. The finer the
required accuracy, the longer the settling time value. This time is typically 20 to 75 ms for an A servo system.
Motion Type Properties
(label 4 in
Figure 81
)
Linear
Select this option for standard linear acceleration and deceleration ramps.
S-Curve
Select this option for ‘S’ shaped acceleration and deceleration ramps that are used to produce smoother motion. You need to
enter the percent jerk value for this option.
(1) At very long cut lengths, the limiting factor, determined by the design speed of the leveler rolls and unwinder, is the maximum line speed. As cut length is reduced, the servo has to index more and more
rapidly until the peak or RMS (root mean squared) torque limit is reached. To cut shorter lengths than this critical length, the line speed must be reduced. Sizing is based on this critical length, maximum
line speed and cut time, which are typically specified.