Siemens simovert masterdrives Compendium

Functions 09.2008
6SE7087-6QX70 (Version AK) Siemens AG
7-44 Compendium Motion Control SIMOVERT MASTERDRIVES
7.2.3.4 Preprocessing of position setpoint
The correction block is used to preprocess the position setpoint. The
correction block can be found in FD789c and is inserted into the time
slot using U953.62.
Its function is to provide the corresponding signals for the position
controller and the position detection.
Example of the connections to the basic unit when the motor
encoder is being used:
Position control [FD340]
position setpoint P190 = 882
Speed setpoint P209 = 881
Position detection [FD330]
correction value P174 = 885
Correct position POV/NOV P175.1 = 889, P175.2 = 890
Enable measurement memory P179 = 891
If a rotary axis is in use, the actual position has to be corrected by
means of the control inputs in order to detect the position correctly.
In the case of homing, the correction value is taken from the position
measurement memory.
Any rate-of-change limitation required is provided at this point in order
to pass the corrected actual value to the positioner (without rate-of-
change limitation) during homing. This (KK0833) causes the position
controller to function as a closed control loop and carry out homing
corrections without any jerks or sudden changes.
This programmable rate-of-change limitation is estimated using an
adaptive connector input (U881).
Rate-of-change limitation is disabled if the parameter has a value of 0
or is assigned a value of 0% from an adaptive connector input.
The values and parameters can be changed if the ramp function
generator is not active (U876 V- set IN = 0).
"Computed" smoothing as found in the "deluxe" ramp function
generator has been dispensed with owing to the amount of computing
time required.
Setting of a homing point on the fly can be influenced through two
movable windows. The points of reference of the windows are based on
the reference position of U874.2 or the source on U877.3 and define
the permissible deviation between the reference position and the
measured position.
The windows allow setting of the homing point to be suppressed if the
deviations are too small or too large.
The contents of the windows are only used when the axis is referenced
(ARFD = 1). The first sensing of the reference mark following runup
leads to a setting of the homing point, irrespective of the window
settings.
Smoothing
adaptation (rate-of-
change limitation)
NOTE
Masking window for
homing
NOTE

Siemens simovert masterdrives Specifications

General

Brand	Siemens
Model	simovert masterdrives
Category	DC Drives
Language	English