SIEMENS
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Siemens D 31 N · March 2016
SINAMICS G120 standard inverters
0.37 kW to 250 kW (0.5 hp to 400 hp)
Control Units
5
■
Function
Functionality of the EPos basic positioner
Lower-level closed-loop position control with the following
essential components
•
Actual position value processing (including the lower-level
measuring input evaluation and reference mark search)
•
Position controller (including limits, adaptation and pre-control
calculation)
•
Position control cycle 8 ms (speed control cycle 2 ms)
•
Monitoring functions (standstill, positioning and dynamic
following error monitoring, cam signals)
Mechanical system
•
Backlash on reversal compensation
Limitations
•
Speed/acceleration/delay/jerk limitation
•
Software limit switches (traversing range limitation by means
of position setpoint evaluation)
•
Stop cams (traversing range limitation using hardware limit
switch evaluation)
Referencing or adjustment
•
Set reference point (for an axis at standstill that has reached
its target position)
•
Search for reference (separate mode including reversing cam
functionality, automatic reversal of direction, referencing to
"output cam and encoder zero mark" or only "encoder zero
mark" or "external zero mark (BERO)")
•
Flying referencing (seamless subordinate referencing is pos-
sible during "normal" traversing with the aid of measuring input
evaluation, generally evaluation, e.g. of a proximity sensor).
Subordinate function for the modes "jog", "direct setpoint
input/MDI" and "traversing blocks")
•
Absolute encoder alignment
Traversing blocks mode (16 traversing blocks)
•
Positioning using traversing blocks that can be stored in the
drive unit including block change enable conditions and
specific tasks for an axis that was previously referenced
•
Traversing block editor using STARTER
•
A traversing block contains the following information:
- Job number and job (e.g. positioning, waiting, GOTO set
jump, setting of binary outputs, travel to fixed stop)
- Motion parameters (target position, override speed for
acceleration and deceleration)
- Mode (e.g.: hide block, continuation conditions such as
"Continue_with_stop", "Continue_flying" and
"Continue_externally using high-speed probe inputs")
- Job parameters (e.g. wait time, block step conditions)
Direct setpoint input (MDI) mode
•
Positioning (absolute, relative) and setting-up (endless
closed-loop position control) using direct setpoint inputs
(e.g. via the PLC using process data)
•
It is always possible to influence the motion parameters during
traversing (on-the-fly setpoint acceptance) as well as for on-
the-fly changes between the setup and positioning modes.
•
The direct setpoint specification operating mode (MDI) can
also be used in the relative positioning or setup mode if the
axis is not referenced. This means that on-the-fly synchroniza-
tion and re-referencing can be carried out using "flying
referencing".
Jog mode
•
Closed-loop position controlled traversing of the axis with
"endless position controlled" or "jog incremental" modes
(traverse through a "step width"), which can be toggled
between
© Siemens AG 2016