s7 300 - power configuration

[Sillver]

Hi,
I'm working on a project where we will use a CPU 314C-2DP with 2 built in IO cards, 1 x SM331 AI, 2 x CP341 and 1 x CP343-1 Lean.

Will each module have a separate connection to the 24VDC supply or will the backplane bus power all the modules

 

[Jeff23spl]

look at the module connections spec, if it need a 24vdc, you could connect with the plc powersupply...

 

[JesperMP]

For S7-300 there basically isnt any 'power configuration' to consider.
The CPU supplies 5V to the modules that attach directly to the right. Any combination of 8 modules (or 1 IM + 8 modules) you can imagine will be covered by the integral 5V power supply.
But some modules do demand a separate 24V supply, the CP343-1 do, and so do output cards.

ET200S is different. There you may have to calculate the power demand going through the backplane.

 

[Sillver]

CP341 and CP343-1 Lean:
If I understand this correctly from documentation here http://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&objId=23523142&nodeid0=24285671&load=content&lang=en&siteid=cseus&aktprim=0&objaction=csview&extranet=standard&viewreg=WW
https://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&objId=31397838&nodeid0=24284824&load=content&lang=en&siteid=cseus&aktprim=0&objaction=csview&extranet=standard&viewreg=WW
the CP341 and CP343-1 Lean require an external connection to the 24VDC. This external supply supplies the input and output circuits of the modules. The maximum current for the CP343-1 Lean will be 200mA and 100mA for the CP341 (for fuse sizes).
Digital I/O’s:
P276: http://cache.automation.siemens.com...0_cpu_31xc_and_cpu_31x_manual_en-US_en-US.pdf
The 24VDC shall be connected to 1L+, 1M to supply any DI’s connected on inputs 2-9, 24VDC connection over 2L+, 2M supplies DO’s connected to 22-29 and so on. The maximum current for the DI’s will be 50mA and 80mA for the DO’s (found here http://support.automation.siemens.c...objaction=csview&extranet=standard&viewreg=WW).

Did I get this right?