Hello,

Please refer attached project of controlling 6RA70 DC drive on Profibus by PLC S7-300.

Used simple instrunctions (for better understanding) & only drive related inputs/outputs are configured. Additional DI/DOs are available for interfacing more I/Os. 

Object of this tip is to help user to understand basic concepts of how to establish communication & transfer/receive basic data.

HTH.

Hello,

MW0 - Memory word which transmits control signals to drive e.g. START, STOP, CW & CCW direction. (M0.0 ... M1.7)

MW16 - Drive speed setpoint.

MW12 - Motor low speed limit

MW14 - Motor max/high speed limit.

MW20 - Drive stastus e.g. drive ready, drive at fault etc. etc.

MW22 - Motor actual speed.

No MW2, MW6 used.

HTH

Hello,

What confusion do you have? Please explain.

Attched file is with .rar extention. Which is project? I cannot open it.

Hi,

Pls see the pic 1, in program PQW 256 is taking value from MW0, where as in pic 2, symbol table PQW 256 is addressed with MW2. Why?

thanks

 Please refer PLC project & VAT table.

Symbol table was created considering few additional logic which remained in table as it is. 

Dear sir,

I am little confused about selection of memory word,in below example you have used MW0 for control single transfer and MW16 for drive speed setpoint.

My  question is that why you choose  MW0 and MW16 ????

Cant you use another memory word???

How to decide which memory word should be use for control signle transfer and drive setpoint ???

{MW0 - Memory word which transmits control signals to drive e.g. START, STOP, CW & CCW direction. (M0.0 ... M1.7)

MW16 - Drive speed setpoint.

MW12 - Motor low speed limit

MW14 - Motor max/high speed limit.

MW20 - Drive stastus e.g. drive ready, drive at fault etc. etc.

MW22 - Motor actual speed.

No MW2, MW6 used}

Regards,

Pankaj Tiwari