Specification Of The Required Control Performance And Selection Of The Control Unit - Siemens SINAMICS G130 Engineering Manual

Specification of the required control performance and selection of the Control Unit

The CU320 Control Unit has been designed to control multiple drives. It provides the control functions for the drives
(Line Modules, Motor Modules) and system components.
The load on the Control Unit will vary depending on the number of individual drives and the required mode of control.
The following data should be used to estimate the load:
Vector control
(also includes V/f control modes)
1 Line Module + 1 Motor Module
Each additional Motor Module
V/f control
1 Line Module + 1 Motor Module
Each additional Motor Module
The respective load data already include central communication applications and the closed-loop control of an Active
Infeed or Smart Infeed. When a Basic Line Module (uncontrolled Infeed) is used, the load is approximately 5 % lower
than with other Line Modules.
The load increases by approximately 1 % per module for each installed Terminal Module.
The total performance requirement is dependent on the scope of functions and control dynamic response demanded
by the application and, above all, by the number of drives to be operated on one Control Unit. Performance
expansion 1 will be required for capacity utilization of 55 % or higher.
Total load Required components
(in addition to the Control Unit)
≤55 %
CompactFlash card
without performance
expansion
>55 % to ≤100 %
CompactFlash card
with performance
expansion 1
>100 % Additional CU320 Control Unit and
CompactFlash card required
The computing capacity requirement or utilization of the CU320 Control Unit can be calculated exactly with the SIZER
configuration tool. The table below also provides a rough guide.
Dynamic response
(current controller
clock cycle)
Servo control 125 µs
250 µs
Vector control 250 µs
400 µs
V/f control 250 µs
400 µs
500 µs
Load
with a current controller cycle of 400 µs or 250 µs
33 or 43 %
19 or 28 %
Load
24 or 30 %
10 or 15 %
(option K90 of S120
Cabinet Modules)
(option K91 of S120
Cabinet Modules)
Number of axes Number of axes
without with
performance performance
expansion 1 expansion 1
3 6
3 6
1 2
2 4
2 4
3 6
4 8
SINAMICS Engineering Manual - May 2008
SINAMICS S120
Engineering Information
Note
Plus one Infeed (BLM, SLM, ALM). No. of axes
applies only to basic scope of functions.
Without extended setpoint channel.
Note power unit derating.
Plus one Infeed (BLM, SLM, ALM). No. of axes
applies only to basic scope of functions.
Extended setpoint channel is a standard feature.
Note power unit derating.
Plus one Infeed (BLM, SLM, ALM). No. of axes
applies only to basic scope of functions.
Extended setpoint channel is a standard feature.
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