Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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Revision A4 www.controltechniques.com
Example:
A user wishes to accelerate from 100% programmed velocity to 175% in 0.5 Seconds. Therefore, the value they need to
enter for Feedrate Decel/Accel is calculated as follows:
3.10.2 Online Tab (not shown)
If online, the following real-time data will be displayed.
Motor Velocity Group
Velocity Command
The Velocity Command is the actual command generated by the drive to the motor in user units.
Velocity Feedback
This parameter is the actual feedback motor velocity in user units.
3.11 Ramps View
The Ramps View allows the user to define various accel/decel ramps used under typical application conditions. By selecting
Ramps in the Hierarchy Tree, the Ramps View will appear on the right (see Figure 46).
Figure 46: Ramps View
3.11.1 Settings Group
Acceleration Type
The Acceleration Type list box display the various acceleration types: 5/8 S-Curve, 1/4 S-Curve, Linear, and S-Curve.
This is used to select the acceleration/deceleration type for all motion (homes, jogs and indexes). The “S-Curve” ramps offer
the smoothest motion, but lead to higher peak acceleration/deceleration rates. “Linear” ramps have the lowest peak
acceleration/deceleration rates but they are the least smooth ramp type. “5/8 S-Curve” ramps and “1/4 S-Curve” ramps use
smoothing at the beginning and end of the ramp but have constant (linear) acceleration rates in the middle of their profiles.
The “5/8 S-Curve” is less smooth than the “S-Curve” but smoother than the “1/4 S-Curve”.
S-Curve accelerations are very useful on machines where product slip is a problem. They are also useful when smooth
machine operation is critical. Linear ramps are useful in applications where low peak torque is critical. Below is a comparison
of the 4 ramp types:
S-Curve: Peak Acceleration = 2 x Average Acceleration
5/8 S-Curve: Peak Acceleration = 1.4545 x Average
1/4 S-Curve: Peak Acceleration = 1.142857 x Average Acceleration
Linear: Peak Acceleration = Average Acceleration
Honor Distance Enable Group
User Ramps/Auto Calculate Ramps
The user has the ability to select one of two ramp control types for the entire motion control system. By default, User Ramps is
selected, The user can change the ramp controls in PowerTools Pro and perform a download to make the change, or the
parameter AutoCalcRampsEnable can be turned On or Off within a program. To enable User Ramps, AutoCalcRampsEnable
should be turned Off, and to enable Auto Ramps, AutoCalcRampsEnable should be turned On. Once a motion profile is in
FeedRate Decel/Accel = Decel Time/ % Change in FeedRate
= (0.5 Sec) / (175% - 100%)
= 0.5 Sec / 75%
= (0.5 Sec) / (100% * 75%)
= 0.66 Sec / 100%