Motion Profiles

What is a Motion Profile?

A profile is a speed, acceleration, deceleration and mode used during a move. The profile specifies how the axis will move to the requested position. Commands that will change the profile are:

Set Mode - Changes the MODE bits.

Change Acceleration - Changes the acceleration rate.

Change Deceleration - Changes the deceleration rate

Set Speed (Unsigned) and Set Speed (Signed) - Changes the speed.

Note: The profile does not include the requested or starting positions.

What is the Motion Profile Table?

The Motion Profile Table stores sixteen motion profiles (Mode, Acceleration, Deceleration, and Speed) in its Flash memory. It is used only for the following communication types:

• PROFIBUS-DP in Compact Mode

• Communication DI/O in Command Mode

• Communication DI/O in Parallel Position Mode

Why use the Motion Profile Table?

In the communication types that use the Motion Profile Table, the PLC can issue only a Command and Command Value in a single command cycle. Therefore, the Go command can only give the Requested Position as the command value, and to set the entire motion profile and give the Go command would require five commands. While this is flexible, it is inefficient.

By using the Motion Profile Table, a complete move including all four motion profile fields can be set with a single Go Using Profile command, speeding up both execution and development time.

How is the Motion Profile Table Used?

When using PROFIBUS-DP or the Communication DI/O in Command Mode, the Go/Set Pressure Using Profile and Open Loop Using Profile commands select one of the 16 motion profiles in the table and use that profile to issue the command.

When using the Communication DI/O in Parallel Position Mode, every command given uses one of the motion profiles. For details, see Using Parallel Position Mode.

How is the Motion Profile Table Changed?

There are two ways to the change the motion profiles table:

• Use the Motion Profile Table Editor. On the Tools menu in RMCWin, click Profile Editor to start this editor; see Editing the Profile Table for details.

• When using PROFIBUS-DP or the Communication DI/O in Command Mode, use the Set Profile commands to change the table from the PLC.

How do I Save the Motion Profile Table?

There are three places where the Motion Profile Table can be saved:

• Flash memory. Use the Update Flash command to store the current profile table in the Flash memory.

• Disk file. The table can be saved to disk from within the Motion Profile Table Editor.

• PLC memory. When using PROFIBUS-DP or the Communication DI/O in Command Mode, use the Set Profile and Get Profile commands to send the table to and from the PLC.

What are the Default Motion Profile Values?

When the motion controller starts, it first does a checksum on the profile table in the Flash memory. If the Flash-stored profile table checksum is correct, it is used. If the checksum is incorrect, then the following default profiles are used:

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