Siemens Simovert Masterdrives Compendium page 768

08.2012
Definitions
Siemens AG 6SE7087-6QX70 (Version AN)
SIMOVERT MASTERDRIVES
Function Use
Engaging cycle For drives that are normally stationary and are only started
[834] up for one operation (e.g. one machine cycle) in
synchronization mode.
Disengaging cycle For drives that are normally used in synchronization mode
[834] and are only stopped for one operation (e.g. one machine
cycle).
Gearbox function For drives requiring a transmission ratio between the
[835] master and slave axis.
Cam [839] For drives whose sequence of movements is to be stored
in a table.
Position A position correction can be superimposed on an angular
correction [843] synchronization. The position correction references the
angular synchronization with external synchronization
markers, e.g. pass marks.
Referencing [843] Referencing "on the fly" to a reference index (e.g. BERO)
during synchronization mode
Synchronization Synchronization of the zero position of the slave axis to
to master value that of the master axis via a parameterizable
[841] compensation movement.
Displacement Setting of a random size of offset (displacement) angle as
setting [841] a fixed value or in inching mode (motorized potentiometer
function)
Catch-up [837] Coupling a drive up to and out of a synchronized drive
system.
The coupled-out drive can be autonomously operated at
local speed and can be accurately halted at a specified
position.
The following section describes some important terms used in angular
synchronization:
Master drive
The master provides the path setpoint for the synchronization block.
There are two types of master: real and virtual.
With a real master [833] , the master position is detected by an
encoder system, e. g. by a master pulse generator mounted on an
upstream mechanical component. The measured position is the path
setpoint for the synchronization block.
Advantage:
Disadvantage: Load impacts and corrections affect the slave
With a virtual master , an ideal position ramp is generated. This ramp
is distributed to all drives. Even the master drive is synchronized with
the virtual master.
Advantage:
Disadvantage: The master drive itself has to be synchronized.
Compendium Motion Control
The slave always follows the master.
directly.
Synchronization has greater overall stability,
since load impacts on the master drive no
longer affect the slave drive.
Technology Option F01
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