Closed Loop Control - Siemens MICROMASTER Vector Operating Instructions Manual

5. OPERATING MODES
Several inverters can be connected to an external control unit at the same time. The inverters can be addressed individually.
Note: If the inverter has been set up to operate via the serial link but does not run when an ON command is received, try reversing
the connections to terminals 24 and 25 .
For further information, refer to the following documents:
E20125-B0001-S302-A1
E20125-B0001-S302-A1-7600

5.7 Closed Loop Control

5.7.1 General Description
The MICROMASTER provides a PID control function for closed loop control (see Figure 5.7.1). PID control is ideal for temperature or
pressure control, or other applications where the controlled variable changes slowly or where transient errors are not critical. This
control loop is not suitable for use in systems where fast response times are required. When closed loop process control is enabled
(P201 = 001), all setpoints are calibrated between zero and 100%, i.e. a setpoint of 50.0 = 50%.
Set point input
Figure : 5.7.1 – MICROMASTER / MIDIMASTER VECTOR Closed loop PID control
5.7.2 Hardware Set-up
Make sure that the DIP selector switches 4 and 5 are correctly set (see Figure 4.1.2) and in agreement with P323 for unipolar voltage or
current feedback signal inputs. Connect the external feedback transducer between control terminals 10 and 11 (analogue input 2). This
analogue input accepts a 0/2 - 10 V or a 0/4 - 20 mA input signal (determined by the setting of the DIP selector switches 4 and 5 and
P323), has 10-bit resolution and permits a differential (floating) input. 15 V dc power for the feedback transducer can be supplied from
terminal 9 on the control block.
© Siemens plc 1999
Application of the
MICROMASTER (German)
Application
MICROMASTER (English)
Proportional
Gain
P202
Integral
Integral
capture
Gain
P207
P203
Differential
Gain
P204
Closed Loop Transducer
Control on/off Type
P201 P208
MICROMASTER Closed loop PID control - Block Diagram
USS Protocol in
of the USS Protocol
Ramp rates,
P002, P003
Scaling
P211
P212
MICROMASTER
39
SIMOVERT Units
in SIMOVERT Units
Motor
Sample Filter
Interval /Integrator
P205 P206
English
6SE21 and
6SE21 and
Process
G85139-H1751-U529-D1
4/8/99