Power supplies for S7- 1500

Hi, Mr. Pegaia,

I have some questions concerning power supplies for S7- 1500. We plan to design a system with a main CPU (6ES7515-2AM01-0AB0) and 8 ET200 MP (6ES7155-5AA00-0AA0). Each of the ET200MP's and CPU by itsself must be supplied seppartely from a central power supply 24VDC (we have chosen the 6EP3337-8SB00-0AY0), which will be supported by UPS. This power sypply will be used for some frequency converters and other Profinet devices as well  and the purpose is to keep the communication and the HMI  active for some time after a failure  in the main powers upply of the machine.

Next to the CPU and each ET there will be a set of digital and analog I/O modules from the basic version (for example: 6ES7521-1BL10-0AA0 ).  We planned to supply the I/O modules and the whole amount of sensors and actors  with a separate power supply of type: 6EP1333-3BA10 or similar in every diiferent switchgear. Each network will be controlled with an insulation control device.

My question are:

1. May we use SITOP power supplies as an alternative instead of the listed S7-1500 devices.

2. Do we need aditional PS on the mounting rail?  We'll not use counters and the highest number of I/O modules on a rail will be 8.

Thank You!

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Split from TIP: Load power supply (PM) x System power supply (PS).

Hi, Ziemens,

thanks for the answer. Could you explain a bit more, were there issues with the overcurrent protections or there was a voltage drop, caused by the long distances? 

My additional questions would be, is there any problem, that we feed the CPU/ET 200 and the I/O modules with differetn sources for S7-1500. For the Simatic S7-300 it was a common practice and now problems were noted.