Setting The Current Limit - Siemens SIMOREG K 6 RA 22 Serie Betriebsanleitung

SIMOREG K
7.1.3.2 Adjustment of speed controller P gain
a) Change jumper-setting from D2-D3 into D1-D2 (speed controller operates as P-action
device).
b) Operate drive at about half the rated speed.
c) Starting from CCW end stop, turn potentiometer R63 / "Kp" slowly clockwise until the drive
starts to become instable (periodic oscillation), the turn back 2-3 scale divisions to reduce
P gain.
If the drive is instable even when "Kp" is at the CCW end stop, change the jumper setting
from B7-B8 to B8-B9 to reduce gain and try again.
If the drive is still not sufficiently responsive when "Kp" is at the CW end stop, remove the
jumper entirely (B7-B8-B9 open) to increase gain and try again..
7.1.3.3 Adjustment of speed controller reset time
a) Change jumper setting D1-D2 into D2-D3 (speed controller operates as PI-action device)..
b) Operate drive at about half the rated speed.
c) Starting at CW end stop, turn potentiometer "Tn"/R81 slowly counter-clockwise until the drive
starts to become instable (periodic oscillation), then turn "Tn" clockwise by 2-3 scale
divisions to increase the reset time.
If the drive is instable even when "Tn" is at the CW end stop, then the capacitance of
capacitor C96 must be increased and step c) repeated..
7.1.3.4 Supplementary functions of speed controller
a) Actual speed value smoothing
The "as supplied" setting of the actual speed value smoothing constant is 0.5 ms. In special
cases (e.g. gearbox backlash) the smoothing time constant must be increased by fitting a
higher-valued capacitor C40.
Measuring point ∆n as adjustment guide
b)
The difference between the actual speed and reference values can be measured at
measuring point ∆n. This measuring point is therefore suitable for the connection of a high-
speed recorder to record the transient response of the speed controller.
7.1.3.5 Note
Asymmetry in the actual current signal (beginning periodic oscillation) may occur with a high
P gain setting. In this case, the speed controller must be set to uncritical values. The permissible
P gain is lower for EMF control (tacho-less operation) than for speed control with tachogenerator.
The actual current signal can be checked by connecting a high-speed recorder or an oscilloscope
to measuring point i.
7.1.4 Setting the current limits
The output of the speed controller is the current reference of the current controller; it is limited by
the potentiometer "B+". The setting range is 0...100% of the rated converter current; the setting is
made according to the desired acceleration current of the motor. The current limit can be input
from an external low-impedance source via terminal X24:19. The potentiometer setting is then
ineffective.
Settings
R62 Potentiometer B+
X24.19 Terminal
- 54 -
June 1998
Current limit: CW end stop corresponds to 100%
External input of current limit 0...+10V.
+10V corresponds to 100% of rated converter current
Operating Instructions 6RX1220-0DD74
6RA22 -8DD21-
Siemens AG ATD TD 6