من منتديات شركة سيمنس (( سؤال وجواب ))

طريقة الاتصال بين الحاكمات S7-300/400 من سيمنس تعتمد على الإمكانيات المتاحة في CPU نفسها وقد تكون :

MPI/PROFIBUS وهذه هي الطريقة الافتراضية في كل الوحدات والتي بناء عليها يتم تحديد الاتصال حيث يمكن أن تكون بأحد الوسائل الآتية :

باستخدام PC Adapter USB مثل الصورة التالية



أو باستخدام PC Adapter RS232 مثل الصورة التالية



وهناك باستخدام الحاسب النقال Laptop أو مع الحاسب العادي إن كان هناك منفذ PCMCIA حيث يوجد من سيمنس كارت خاص بذلك يتم وضعه داخل هذا المنفذ وهو CP5512 حيث تعطي هذه الوسيلة إمكانية الاتصال بالكابل البنفسجي كجزء من الشبكة وهذا ما أظن أنك رأيته وهو مثل الصورة التالية



وهناك كارت يتم توصيله على جهاز الحاسب العادي على البورد الرئيسي على منفذ PCI يسمى CP5611-PCI وهو يعطيك أيضا منفذ اتصال MPI/PROFIBUS يمكن توصيله مباشرة باستخدام كابل الشبكة البنفسجي العادي من سيمنس مثل الشكل التالي



ويمكن أيضا أن يكون في وحدة CPU كمنفذ اختياري وسيلة الاتصال LAN ويتم الاتصال فيها بكابل LAN العادي ولكن هذا الاختيار يتم توصيفه في وحدة CPU نفسها وفيها تجد الوحدة عليها الجزء PN بدلا من DP أو مصاحبا له

PID Control for S7-300/400:
The standard function blocks for the different controller functions are provided in the libraries of STEP 7 and CFC and are loaded into the CPUs. In the compact CPU 313C and 314C, these controllers are already available as SFBs (System Function Blocks) in the operating system and do not occupy any user memory. The controllers are parameterized in STEP 7 using a table. The number of controllers that can be implemented results from the available memory space and the resulting overall runtime.

More info at Brochure: "SIMATIC Technology for technological tasks"

About calculation of memory space and etc... look at this example -

For selecting a CPU, you have to estimate the calculation time and memory requirements for your program. A PID controller takes about 0.8 ms in an S7-416 CPU and needs about 6K of storage + 600 bytes for every instance. If you use a cycle of 1 second this means that you could get a maximum of 500/0.8 = 625 controllers in this cycle (without any other logic!!!). If you go for a 5 second cycle, this would of course be 5 times more. The memory required for this 625 controllers would be 6K + 625*600 = 372K, again without any other program parts. If you take a slower CPU, the execution time of the PID block is bigger, so less would fit in the same cycle. If you are going to automate a process plant with the CPU, I would opt for the PCS7 engineering toolkit, as this offers more convenient ways to design process automation programs with CFC,SFC and SCL programming languages and PID controllers ready made with more options than the bare PID algorithm of the FB41 (auto/manual, internal/external setpoints, engineering units, alarm limits, etc...).

Answers here are for S7-300 CPUs. If you are using another, please specify, or better still search for the appropriate manuals on the forum search box.

S7-300 CPUs instruction list :

http://support.automation.siemens.com/WW/view/en/31977679

S7-300 Module data manual (look at the chapter on analog modules):

http://support.automation.siemens.com/WW/view/en/8859629

High Speed Analog Input Module 6ES7 331-7HF01-0AB0 : basic coversion time per chanel is 52 micro second; the execution time of the module will vary depending on the filter time selected.
To read at that speed you will also need to sue a cyclic OB set at 10 ms, which will task your processor. Make sure you test this before you implement this in your plant.

There is a switch on the side - so you can configure it to any mentioned type of signal. Please ensure HW Konfig has the same configuration. I've tried it with pt100

You have to be sure that the setting in HW config is correct according to type of your transducer and also it should meet the setting of the black squares in the side of the module itself. Please see the picture.