Ramp Generator; Ramp Generator - KEB COMBIVERT F5 MULTI Applications Manual

Functional Desription
6.4.7

Ramp generator

Fig. 6.4.7 Acceleration and deceleration times
+n [rpm]
1000
500
∆ n
∆ t
0
oP.28
800
1000
*1 If the value ÑForì is adjusted in these parameters (acceleration and deceleration times for rotation
-n [rpm]
direction reverse), then the values for rotation direction forward (oP.28 und oP.30) are valid.
*2 If the value ÑAccì is adjusted in this parameter, then the value for acceleration (oP.28) is valid.
Time factor acceleration/
deceleration (oP.62)
Example
Chapter Section Page
6 4 14
The ramp generator assigns an adjustable time to a speed change, during this time
the change stall take place. The acceleration time (for pos. speed changes) and
deceleration time (for neg. speed changes) can be adjusted separately for both directions
of rotation. To enable jerk-free acceleration and deceleration, so-called S-curves can
be adjusted in addition to it.
The ramp times refer to 1000 rpm (at ud.3=0) and change in proportion to the mode.
The times to be adjusted are calculated as follows:
desired ramp time
ñññññññññññññññññññññññññññññññññ
ramp time to be adjusted (oP.28...oP.31)
∆ n
∆ t
oP.30
The time factor extends the standard ramp time (oP.28...31) by the adjusted value.
The S-curve time do not change.
Value Ramp time
0 adjusted value x 1
1 adjusted value x 2
2 adjusted value x 4
3 adjusted value x 8
4 adjusted value x 16
Calculation of the
acceleration and
deceleration times:
A drive shall accelerate from 100 rpm to 1000 rpm in 5s.
Date Name: Basis
12.05.04 KEB COMBIVERT F5-M / S
Setpoint- and Ramp Adjustment
oP.28
oP.29 *
oP.30 *
oP.31 *
∆ n
∆ t
oP.29 * 1
∆ t
∆ n
oP.28...oP.31 = ñññññññññññññññññññññ
5s x 1000 rpm
oP.28 =ó ó ó ó ó ó ó ó ñ ñ ñ ñ ñ ñ ñ ñ = 4 , 5 s
1000 rpm -100 rpm
speed change (∆n)
= ñññññññññññññññññññ
1000 rpm (dep. on ud.2)
Acceleration time forward
1 Acceleration time reverse
2
Deceleration time forward
1 Deceleration reverse
Frequency change
Acceleration time for ∆ n
oP.31 * 1
∆ t
∆ n
1000 rpm x real ramp time
∆n
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