SIEMENS
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Siemens CR 1 · 2015
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Design
(continued)
SIMOCRANE Standard Technology
SIMOCRANE Basic Technology
SIMOTION SCOUT Engineering Software
Technology functions
Crane-specific technology functions
No.
Function
Brief description
1
Load-dependent field weakening
Using the DCC block, a supplementary speed setpoint is calculated dependent on the
load. This speed increase for partial loads above the rated speed is required for cranes
to increase the handling capacity.
2
Prelimit switch (selectable limiting)
The velocity of the drive can be limited using the DCC block when a pre-defined
prelimit switch is reached.
3
Start pulse
Using the DCC block, "load sag" when starting hoists with a suspended load is
prevented.
4
Switch-over of the ramp-function generator in the field-weaken-
ing range and when selecting heavy-duty operation
Using the DCC block, the acceleration and deceleration times are modified for
heavy-duty operation or in field weakening.
5
Current distribution monitoring
Using the DCC block, the current setpoint/actual values from the master and slave
are monitored. A signal is generated if a specified difference is exceeded.
6
Slack rope controller
This function prevents a slack rope developing in the goods being handled when
the grab is closed. The slack rope controller also ensures that the grab can bury itself
into the material to be moved and therefore ensuring the maximum filling level.
7
Current equalization control for orange-peel bucket operation
When raising and lowering the closed grab, the tension levels in the holding and
closing ropes should be approximately the same. This means that the hoisting power
is optimally distributed across the two motors.
8
Slewing velocity dependent on the length of overhang
The speed of the slewing gear is adapted depending on the luffing gear length of
overhang in order to keep the circumferential velocity constant.
9
Ramp-up/ramp-down time dependent on the length of over-
hang + influence of the ramp-function generator dependent
on the velocity
For cranes with luffing gear, with increasing length of overhang, the load torque for the
slewing gear increases while accelerating. In order to avoid that the current limits are
reached, the ramp-up and ramp-down times are linearly adapted as a function of the
length of overhang.
10
Master switch
Using the DCC block, the drive can be moved with a fine sensitivity using the master
switch for manual positioning.
11
Anti-slip control
The velocity between the motor encoder and the external encoder is monitored using
the DCC block. If an excessively high velocity deviation occurs, the velocity or the
acceleration is adapted in steps.
12
Heavy duty or constant field weakening
With the DCC block, the drive becomes capable of heavy-duty operation (HeavyDuty)
or operation with constant field weakening (FieldWeak) through variation in the velocity.
13
Monitoring for overspeed
For hoist applications, using the DCC block, an overspeed condition is monitored
or a setpoint-actual value deviation is detected (this is not a fail-safe function).
14
Monitoring the setpoints
The DCC block is used to monitor whether the velocity, acceleration or deceleration
have been reduced between the command being output from the S7 and implementa-
tion in the drive. Further, it is monitored as to whether the drive is in field weakening.
15
Continuous load measurement
This DCC block is required for grab cranes. A continuous load measurement is carried
out to guide the crane driver if the grab is not visible. The message "Grab touchdown"
is also displayed.
16
Grab monitoring
In the case of closing gear, the block DCC GrabMonitor can be used to detect bulky
load material.
17
Time-optimized positioning for a single axis
Using the SIMOTION system function, the drive can be moved to the target position as
quickly as possible and precisely with the specified maximum velocity and accelera-
tion/deceleration.
18
Master-slave closed-loop torque control
Master-slave operation is used if 2 motors are connected to a common shaft. The mas-
ter operates either closed-loop position controlled or closed-loop speed controlled
depending on the operating mode. The slave only operates closed-loop torque con-
trolled. The master sends the torque as torque setpoint to the slave.
19
Synchronous operation
Synchronous operation control is used if 2 motors are connected to a common load.
Depending on the operating mode, the master and slave operate either closed-loop
position controlled or closed-loop speed controlled. The slave receives a speed or
position setpoint depending on the operating mode from the master via a gear (gear
ratio 1 : 1). The functional scope has been expanded with the implementation of flying
referencing/homing, offset compensatory control, establishing/canceling fixed offset,
and cornering movement.
20
Tandem operation
Tandem operation is an extension of the synchronous operation control mode.
Synchronous operation motion control takes place between 2 groups. In each group,
2 drives can be coupled in master-slave closed-loop torque control or also in synchro-
nous operation. The function is suitable to address applications for both harbor cranes,
such as a double spreader container crane or large ship unloaders with 4 drum grabs,
as well as industrial cranes with several hoists and trolleys.
21
Cornering movement
Using this function, cornering movement for crane long travel (gantry) can be executed
in closed-loop speed controlled operation.
22
Brake test
The mechanical brake function (e. g. hoist) should be regularly checked using this
function. To do this, the axis moves against the closed brake with a certain torque
setpoint in order to check the braking capability of the brake.
23
Basic positioning
This is a positioning that does not use the position controller of the axis but is calcu-
lated in the Crane FB Library; it is suitable for systems that tend to be subject to
mechanical vibration, such as trolleys on STS cranes.
© Siemens AG 2015