Siemens SIMATIC FM 353, Manual

Page: 224 / 361

Description of Functions
9-24
FM 353 Stepper Drive Positioning Module
6ES7 353-1AH01-8BG0
9.2.4 Incremental relative
Overview
In the Incremental Relative mode it is possible to execute single positionings over
relative distances using user-definable increments.
The traversing movement is triggered with the direction keys (R+ and R − ).
Defining the position
The options available for defining the increment with the mode parameter are:
S
Via the user program by defining a position for incremental mode
(user DB, DBX38.2)
The setpoint for the incremental dimension must be entered in the AW-DB,
DBD156, before the write order is initiated.
S Using the increment table; see Section 5.3.2
Speed level 1 (user DB, DBX38.0, see Section 9.2.1) is used as speed setpoint,
and can be modified while the movement is in progress.
On-the-fly position changes (e.g. changing of the position setpoint during the
course of a movement) is
not possible.
Handling by the user
The table below gives you an overview of how to handle this mode.
Triggering of
movement, Direc-
tion (R)
Increment selection Position,
Distance to be traveled
R+ or R −
BP = 254 in accordance with the setpoint
for incremental dimension (user
DB, DBX38.2)
BP = 1...100 as in SM table (DB-SM)
Position setting
Name Lower input limit Upper input limit Unit
Increment 0 1 000 000 000 MSR
MSR stands for measurement system raster (see Section 5.3.1)
Note the following when interrupting a movement with “Stop”:
S To continue movement in the same direction - the residual distance is pro-
cessed with the appropriate direction key.
S To continue movement with “delete distance to go” (user DB, DBX37.1), the
remaining distance to go is deleted and the incremental dimension is again trav-
eled (provided the incremental dimension was not changed).
S To position in the opposite direction - the residual distance is deleted automati-
cally.