Which adress to use like a S7 1200 to have manual / automatic switch (sRet.i_Mode) on a S7 300?

hello

It's not the same on a S7-300

Which adress to use like a S7 1200 to have manual / automatic switch (sRet.i_Mode) on a S7 300 ?

If you want that the PID runs in automatic mode without automatic optimization, you need:
a. Set the checkbox “Use manual PID parameter setting“, in the Configuration, tab “Advanced settings”.
b. Set “3” to the variable “sRet.i_Mode” of the respective instance DB
c. Extra tips:
a. if you intend to Set the checkbox “Use manual PID parameter setting“, do it, but after that change the mouse focus before to close the Configuration windows. Else your check will be loose.
b. Follow I attached a minimal sample program
To work:
1 - Adapt it to your hardware.
2 - Download it
3 - Open the Watch Table PID and go online. Set the alread selectioned values.
d. Avoid overrange values to Process Values. Use Limit instruction for float point PV. Take a look at FAQ "How can you prevent your S7-1200 PID Compact controller from going inactive in the case of a PLC power cycle and invalid process values?" (http://support.automation.siemens.com/WW/view/en/46163827)

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Thanks

really ?

i have erase all my db parameter and all my 20PID blockstart in manual....

I have NO input in the PID bloc to switch in manual...

Pegaia

Hi,

the S7-300 PID is very simple.

You has an input MAN_ON to do this control:
MAN_ON= true => MAN input is copied to output.
MAN_ON = false => PID runs in automatic mode.

Hello

i have found the problem

On my program there is nothing connected to Manual.

In fact the generated DB of the PID in the DB_PID.DBX42.1 initial manual value is ON !

need toput off at firstscan !

Thanks everybody!