Siemens Simatic S7-1500 / ET 200MP - Use of System Power Supplies

Application planning
5.2 System and load power supply
Automation system
System Manual, 01/2023, A5E03461182-AK
113
5.2.1 Use of system power supplies
Introduction
You can use system power supplies with the CPUs and the interface modules IM 155-5 PN ST
and IM 155-5 PN HF.
If the power fed from the CPU/interface module into the backplane bus is not sufficient to
supply all connected modules with power, system power supplies (PS) are required.
Whether or not you need a system power supply depends on the power consumption of the
modules used. The power supplied by the CPU/interface module and the system power
supplies must be greater than the power required by the I/O modules.
During configuration, STEP 7 compares the supplied power and the power required by the
modules. If the required power is too high, you receive a corresponding message from
STEP 7.
In addition, the system power supply PS 60W 24/48/60V DC HF buffers the power in the event
of power failures and therefore enables the retentivity of the data of a CPU – without a
battery and therefore maintenance-free.
Slots for system power supplies
The following slots may be used for system power supplies:
• A system power supply in slot 0 to the left of the CPU/interface module
• Up to 2 system power supplies in the slots to the right of the CPU/interface module (power
segments) A power segment consists of a power supply module and the modules supplied
by it.
Note
The system power supply PS 60W 24/48/60V DC HF can only be inserted in slot 0.
Power segment
The following applies for the CPUs and interface modules M 155-5 PN ST and IM 155-5 PN HF:
If you are using system power supplies to the right of the CPU/interface module, divide the
configuration into power segments.