SP: 

Hello Ahmad;

You seem to  have an idea about programming the S7-200 as a Modbus RTU master.

Do you know how the drive operates as a Modbus RTU slave? You need to search the manufacturer's website for Modbus manuals for your model of drive, look especially for the Modbus mapping it uses. This is a list of registers inside the drive that a master can read in and write to in order to control it.

Just in case you are not completely familiar with Modbus exchages, our friend smiffy has written an excellent presentation on the subject that many have found useful, as an introduction or a refresher. You will find it here;

Modbus general description

https://support.industry.siemens.com/tf//us/en/posts/modbus-general-description/66876/?page=0&pageSize=10

Hope this helps,

Daniel Chartier 

Hello,

You have to get a manual of production and have a look to modbus RTU code and register table 

for example actual speed 40012 or some thing like that.

Exactly.

Without the ModBus addresses on the inverter, it will take some time to figure that out.

At the link below is also a example how to use modbus wit ha s7 200

https://support.industry.siemens.com/cs/ww/en/view/27832511