Siemens SINAMICS S120 Manual page 25

3 DCC Blocks
Mode of Operation
Once the command for p21736 (boCommandSlowSpeedUp) or p21737
(boCommandSlowSpeedDown) is made, motion will begin in respective direction,
up to the speed set in p21739 (rSlowSpeed (%)). Once speed set in p21739
(rSlowSpeed (%)) is reached, speed will remain constant. Once the command for
p21737 (boCommandAccelerate) is made, speed will begin to ramp up to
maximum set speed, over a ramp time set in p21738 (rRampTime (ms)). If p21737
(boCommandAccelerate) is released before the maximum speed set in p21740
(rMaxSpeed (%)) is reached, then the speed will remain constant at the last
achieved speed. Once the command to accelerate is given again, the speed will
continue ramping up to the maximum speed until it is reached, then that speed is
held constant even if the command to accelerate is no longer there
(boCommandSlowSpeedUp or boCommandSlowSpeedDown must still be held
active). To ramp down the speed, the signal for boCommandSlowSpeedUp or
boCommandSlowSpeedDown must not be present, and speed will begin to ramp
down over the ramp down time set in SINAMICS p1121 (Ramp-function generator
ramp-down time).
1
boCommandSlowSpeedUp
0
1
boCommandAccelerate
0
Frequency Output
Figure 3-1 Infinite Variable Speed graphical representation of the mode of operation
Connections
Table 3-5-6 Infinite Variable Speed connections
SINAMICS
parameter
number
p21734 boEnable
p21735 boCommandSlowSpeedUp
p21736 boCommandSlowSpeedDown
p21737 boCommandAccelerate
p21738 rRampTime (ms)
Extended Crane Drive-Based Technology AC
Extended Crane Drive-Based Technology SINAMICS S120
DCC Add-On Description 109767457,
Name Connection
type
V1.2, 09/2019
Default
assignment
IN 0
IN 0
IN 0
IN 0
IN 2000
rMaxSpeed (%)
rSlowSpeed (%)
Data Meaning
type
Enables analog infinte
BOOL
variable speed
BOOL Command to move in
positive direction at
slow speed
parameterized in
p21739
BOOL Command to move in
negative direction at
slow speed
parameterized in
p21739
BOOL Acceleration from
current speed to max
speed (p21740) over
ramp time (p21738) as
long as signal present
REAL Ramp up time
25