Siemens 611-D, 840C S S

Meas.

parameter

09.95

9–20

SINUMERIK 840C (IA)

9.2.6 Position control loop (axis and spindle) – measurementparameters (9 basic settings – as from SW 3)

Overview of types The types of measurement listed below are not dependent on the drive used.

of measurement Various variables can be measured depending on the measurement type

selected.

Type of

measurement Measured quantity

Position actual

value

Measured quantity

Following error Measured

quantity

Speed actual

value

1.) Frequency re-

sponse analog / 611D – –

2.) Setpoint step

change analog / 611D analog / 611D analog / 611D

3.) Setpoint ramp analog / 611D analog / 611D analog / 611D

D1st measured type: Frequency response

The frequency response measurement determines the response of the position

control loop in the frequency range. The balancing filter, KV value and feedfor-

ward control must be parameterized such that resonance is avoided wherever

possible over the entire frequency range. Excessive resonance requires

Sincrease in balancing filter

Sdecrease in KV value

In the case of dips in the frequency response, the setting of the feedforward

balancing filter should be reduced. If these measures do not lead to an improve-

ment, then the setpoint can be rounded by means of a smoothing filter. The

effects of this filter can be checked in the test functions in the time range (step

and ramp stimulation).

You can select the menu with the parameters for measuring the position control

loop with this softkey.

Note You enter the measurement parameters in the selected display. These parame-

ters are managed internally as configuration data rather than machine data, i.e.

they are not initialized when the machine runs up. Data can be input in two diffe-

rent ways:

SManual input

SInput by loading of an existing, complete data set with the aid of file functions

Measurement SAmplitude

parameter settings This parameter determines the magnitude of the test signal amplitude.

SOffset

The measurement requires a small speed offset of a few motor revolutions

per minute. The offset value must be set higher than the amplitude value.

SBandwidth

Setting of frequency range to be analyzed (must not exceed a value corres-

ponding to half the speed controller sampling frequency). The lower this va-

lue, the finer the frequency resolution will be and the longer the measurement

time.

max.band width fsampl.

21

2xt

sampl.

e.g. 0.5 kHz with position controller sampling time of 2 ms.

9 Drive Servo Start-Up Application (as from SW 3)

9.2.6 Position control loop (axis and spindle) – measurement parameters (9 basic settings – as from SW 3)

07.97