Any Siemens PLC programmers out there?

dtfeld · Mar 22, 2011

Have an S7-1200 with 2 4x RTD inputs modules. I've got the basics down but I'd did Omron 10-15 years ago and could use a little help with some of the functions and terminology of Siemens.

Wberry · Mar 22, 2011

What are you looking to do?

dtfeld · Mar 23, 2011

I've got a lot of questions!!! Ive been reading their manuals and working some basic functions but the PID and tuning it are killing me.

Really I been looking for some sample ladder to see how it's done and go from there.

The scope of the project is to control 2 pumps and 2 heaters on my single tier Hermes system. The firm ware isn't there yet but eventually I'd like to use the web server function with WinCC on a laptop to act as a virtual HMI.

Problem right now is I just haven't hit the critical mass of Siemens knowledge to pull this off just yet.

I speak ancient Japanese, not new age German!

BrewKnurd · Mar 23, 2011

dtfeld said:
I've got a lot of questions!!! Ive been reading their manuals and working some basic functions but the PID and tuning it are killing me.

Really I been looking for some sample ladder to see how it's done and go from there.

The scope of the project is to control 2 pumps and 2 heaters on my single tier Hermes system. The firm ware isn't there yet but eventually I'd like to use the web server function with WinCC on a laptop to act as a virtual HMI.

Problem right now is I just haven't hit the critical mass of Siemens knowledge to pull this off just yet.

I speak ancient Japanese, not new age German!

I work as a control systems engineer, so PID control and tuning are part of my job.

haven't had specific experience with siemens plcs but have dealt with others. I'm willing to help if I can.

dtfeld · Mar 23, 2011

The biggest issue right now is how to input the setpoint for the PID. The PID element sets up a database but I can't find a way to just drop a value into it.

I think there must be a data move function but I have been unable to find or understand how that's done

BrewKnurd · Mar 23, 2011

dtfeld said:
The biggest issue right now is how to input the setpoint for the PID. The PID element sets up a database but I can't find a way to just drop a value into it.

I think there must be a data move function but I have been unable to find or understand how that's done

Yeah, that's probably more siemens specific than I'm gonna be able to help with. Most plcs I've dealt with, you would either create a local variable and link it up to the pid block, or click on the input to the block and define it there. Are you using function blocks?