Siemens simatic ET 200MP, System Manual

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Application planning
4.2 Power budget calculation
ET 200MP Distributed I/O System
System Manual, 01/2013, A5E03723484-01
35
In the following example calculation the power budget for a configuration is determined.
Table 4- 2 Sample calculation for power budget
Modules Power
Incoming power to the backplane bus
IM 155-5 PN ST 14 W
Power from the backplane bus
Analog output module AQ 4xU/I ST 0.6 W
Analog input module AI 8xU/I/RTD/TC ST 0.7 W
Digital output module DQ 32x24VDC/0.5A ST 1.1 W
Digital input module DI 32x24VDC HF 1.1 W
Analog output module AQ 4xU/I ST 0.6 W
Total requirement 4.1 W
Result
Power budget 14 W - 4.1 W = 9.9 W
Result: The power budget is positive (9.9 W > 0). If it had been negative (< 0 W), then an
additional power supply module would have been required.
Up to 12 I/O modules may be operated on the power segment of the IM 155-5 PN ST
interface module, as long as the total power drawn by the I/O modules is < 14 W.
Reference
Further information on the performance values (power feed, power consumption) of the
interface module, of the power supply module, and of the I/O modules can be found in the
Product Manuals of the respective modules.