S7300 hardware configuration and module power consumption calculation method

With S7300 313C of CPU added IM365 again extended a machine frame. 313C itself since with 24DI16DO and the simulation entered output 5AI/2AO, see Configuration Manual above CPU behind can placed 8 a module, wants to will about, CPU itself integrated of I/O surface to except did? is regardless of is what CPU Hou end are can placed 8 a module, (manual Shang CPU right shall not installation eight a above of module (SM, and FM, and CP). The cumulative power of the module installed on the rack at S7-300 on the backplane bus must not exceed 1.2 a. ) Cumulative power don’t know what refers all 5V power consumption on a rack? don’t know understand,digital input not available 5V power consumption, only digital outputs and analog inputs and outputs can be found to the 5V power consumption values, use the IM365 extended time frame 1 module can only receive signals; the cumulative current load limits
1.2 a, Bay 1 maximum current of 0.8 a, understandable Bay 0 1.2A Bay 1 maximum can only be calculated 0.8A is it?

The best answer
1, rack according to how many modules problem?
CPU rack called a host when the host rack I/O module (up to 8) of control points is not enough, you can add 1-3 extension rack, each extension rack up to 8 I/O modules, 3 rack up to 24 I/O extension modules.
2, the S7-300 on the backplane bus must not exceed 1.2 a question?
Host backplane bus current is provided by the CPU modules in order to enable theCPU to find the module. Expansion rack backplane bus current is by extension Rackinterface module (IM) to offer. Note that the 5V power supply not power supply module, look know, power supply module is not u-bus connector, CPU modules and extend the rack interface module (IM) u have a backplane bus connector.
U-S7-300 backplane bus connector role and delivers 5V power supply, another roleof the bus connector is communications bus.
No need to take into account the cumulative current load for 5VDC, 8 I/O modulesdo not exceed the sum of 1.2 a/0.8 a Max.
In other words, the CPU module and interface module (IM) up to 8 I/O modules can be installed on the right side, the CPU module and the control module (IM) completely has the ability to provide maximum load 5V power supply.
3, or about 1.2 a 0.8 a?
CPU module with extended Rack interface module (IM) to provide 5V power supply1.2 a/0.8 a, respectively.