Velocity For Automatic Lowering - Siemens SIMOTION D4x5-2 DP/PN Operating Instructions Manual

Sway Control function description

6.25 Velocity for automatic lowering

Figure 6-43
6.25 Velocity for automatic lowering
It is possible to reduce the velocity automatically shortly before the target when placing the load
in semi-automatic mode (SAM). This prevents the container from being placed at an
excessively high velocity. Reducing the velocity before placement also corresponds to the
usual procedure employed by crane drivers.
Two parameters are used to achieve this:
● P49: Velocity reduction when lowering (relative to P41)
● P74: Hoisting distance for automatic lowering
Example calculation:
P49 = 0.2 and P74 = 200 mm
200 mm before the target, the velocity is 20% of the positioning velocity (P41). The braking
operation is therefore initiated shortly before 200 mm is reached, so that the target velocity has
already been achieved when 200 mm is reached.
Limiting takes place on the land and water sides, but only when lowering.
These targets can be either internal (target generator) or external (higher-level control system).
For this reason, the function is not absolutely linked to a particular position. The position is
target-dependent and variable as a result.
The absolute hoist position can deviate slightly from the encoder value due to load-dependent
rope elongation. This function makes it possible to set the actual target a little lower so as to
compensate for variations in rope elongation. The limiting function then ensures that the
226
Minimum hoisting height 2
SC integrated STS, GSU
Operating Instructions, 07/2019, A5E48271265B AA