2 ramp-function generator (rfg), With ro undin g – Watson-Marlow MM440 User Manual
Page 183
Issue 10/06
3 Functions
MICROMASTER 440 Operating Instructions
6SE6400-5AW00-0BP0
183
3.12.2
Ramp-function generator (RFG)
Parameter range:
P1120, P1121
r1119, r1170
P1130 – P1142
Warnings -
Faults -
Function chart number:
FP5000, FP5300
The ramp-function generator is used to limit the acceleration when the setpoint
changes according to a step function. This therefore helps to reduce the stressing
on the mechanical system of the machine. An acceleration ramp and a braking
ramp can be set independently of one another using the ramp-up time P1120 and
the ramp-down time P1121. This allows a controlled transition when the setpoint is
changed (refer to Fig. 3-62).
Without roun
ding
t
f
f
max
P1120
P1121
f
2
f
1
f
f
max
P1133
P1132
P1131
P1130
t
f
2
f
1
t
up
t
down
With ro
undin
g
for
P1131)
P1130
(
2
1
P1120
P1082
f
-
f
1
2
+
≥
⋅
P1120
P1082
f
-
f
P1131)
P1130
(
2
1
t
1
2
up
⋅
+
+
=
for
P1133)
P1132
(
2
1
P1121
P1082
f
-
f
1
2
+
≥
⋅
P1121
P1082
f
-
f
P1133)
P1132
(
2
1
t
1
2
down
⋅
+
+
=
Where the rounding times are increased to be greater than the ramp period then the ramp
period is determined by the following equations:
(
)
(
)
(
)
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
+
⋅
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
+
⋅
⋅
⋅
−
⋅
=
1130
P
1131
P
1
1131
P
1130
P
f
1130
P
1120
P
f
f
2
t
max
2
1
2
up
(
)
(
)
(
)
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
+
⋅
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
+
⋅
⋅
⋅
−
⋅
=
1132
P
1133
P
1
1133
P
1132
P
f
1132
P
1120
P
f
f
2
t
max
2
1
2
down
Fig. 3-62
Ramp-function generator