Emerson FM-3 Network Card User Manual


 
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FM-3 Programming Module Reference Manual
Acceleration and Deceleration ramps may be enabled on the Gearing setup screen as seen in
Figure 61 above (B3 firmware or later is required for Accel / Decel). If enabled, the accel and
decel ramps are specified in units of Follower Units / Velocity Time Base / Acceleration Time
Base. Note that this is a Realtime ramp. Therefore, the time that it takes to reach the
programmed ratio depends on how fast the master is traveling when gearing is activated.
Figure 62 below demonstrates that the faster the Master Velocity, the longer it will take to
reach the programmed ratio. If the Master Axis is not moving when gearing is initiated, then
the follower locks into its programmed gear ratio instantly (no acceleration time required).
Figure 62: Gearing Acceleration Ramp Description
The GearRatio can be changed on the fly (while in motion), but acceleration or deceleration
must be enabled to use ramps to achieve the new ratio. If gearing accel and/or decel ramps
are not enabled, the motor will attempt to achieve the new ratio in one trajectory update
(800<t<16000 microseconds).