Control Techniques FM-3 Reference Manual page 71

= Index 0
= Index 1
V
1250
1
500
Compound Index
User Ramps
1. Index.0.Accel specified by user is used to accelerate up to Index.0.Vel. Index.0.Accel is aggressive enough to reach
Index.0.Vel within Index.0.Dist of 5 Revs. Since indexes are compounded together, Index 1 begins at Index.0.Vel.
2. When indexes are Blended, Index 0 should end at velocity of Index 1, but Index.0.Accel is not aggressive enough to reach
Index.1.Vel within Index.0.Dist of 5 Revs. Therefore, entire distance of Index 0 is used to accelerate towards
Index.1.Vel.
3. Acts the same as the Compound with User Ramps because Index.0.Accel entered by user is aggressive enough to reach
Index.0.Vel of 500 RPM. If Index.0.Accel entered by the user was not aggressive enough to reach 500 RPM within 5
Revs, necessary ramp would be calculated.
4. Acceleration ramp is automatically calculated to reach Index.1.Vel within Index.1.Dist of 5 Revs. If user had entered a
ramp aggressive enough to reach Index.1.Vel within 5 Revs, no automatic ramp calculation would be required, and the
user entered acceleration rate would be followed.
Figure 46: Ramps Examples of a Slow Index to a Faster Index
Ramps Group
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.
Feedhold Decel/Accel
When the Feedhold destination is activated, the motor will decelerate to a stop in the time specified by the
FeedholdDecelTime parameter. When feedhold is cleared, the motor will accelerate back to speed in the same specified
period of time.
Feedhold is a means to halt the motor within a velocity profile and then return to the profile later at the exact same place in
the profile. Feedhold does not ramp and does not decelerate in terms of velocity. Instead, it stops by decelerating time. For
Distance
(Revs)
Index 0 5
Index 1 20
2
Blended Index
User Ramps
Velocity Accel
(RPM) (RPM/sec)
500 1000
1250 2000
3
Compound Index
Auto Ramps
Setting Up Parameters
Decel
(RPM/sec)
1000
2000
4
Blended Index
Auto Ramps
t
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