software.

If an absolute index is used with a non-zero rotary rollover point, the SM-EZMotion will calculate the shortest path to its destination and move in the required direction.

To force the motor to run a certain direction, use the Rotary Plus or Rotary Minus type of indexes.

7.3.5 Velocity View

The Velocity View allows the user to define parameters related to the velocity control of the SM-EZ Motion module. Figure 69 shows an example of the Velocity view.

Figure 69:

Velocity View

Feedrate Override

This parameter is used to scale all motion. It can be described as scaling in real time. The default setting of 100% will allow all motion to occur in real time. A setting of 50% will scale time so that all moves run half as fast as they do at 100%. A setting of 200% will scale time so that all moves run twice as fast as they would at 100%. FeedRate Override is always active and affects all motion, including accels, decels, dwells, and synchronized motion. This parameter may be modified via Modbus or in a program.

Feedrate Accel/Decel

The FeedRate Decel/Accel parameter specifies the ramp used when velocity changes due to a change in the FeedRate Override value. The units of feedrate decel/ accel are Seconds/100% of FeedRate. Therefore, the user must specify the amount of time (in seconds) to accelerate or decelerate 100% of FeedRate.

7.3.6 Ramps View

The Ramps View allows the user to define various accel/ decel ramps used under typical application conditions. Figure 70 shows an example of the Ramps view.

Figure 70: Ramps View

Acceleration Type

Press the arrow by the Acceleration Type list box. It will 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

Stop Deceleration

The value you enter here defines the deceleration rate which is used when the Stop destination is activated. The default is 100 RPM/second.

The Stop destination is found in the Ramps Group in the Assignments view.

Configuring an Application

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Emerson P/N 400361-00 manual Velocity View, Ramps View