QuoteCan i declare dsqc 352 as a master and control BK3120?
No DSQC352 is only DP Slave.
QuoteOr both dsqc 352 and BK3120 are slaves and thaey cannot be controlled without external Master Profibus PLC?
Yes, both Devices are Slaves and must be controlled by a external PD Master
QuoteBut the main question: Is it possible to connect dsqc 352 (Profibus I/O) with Beckhoff BK3120?
No, that not the Right description. You can not direct connect the DSQC352 with the BK3120
the DSQC352 is connected to the external Master
and
The BK3120 is also connected to the same external Master
the job of the master is now read the data from the Robot an send to Fronius, and the other way around
Quote2) --- Beckhoff BK5250 (DeviceNet) with KL6021(localNet), BK9010
Yes , The best way is, you have a Devicenet Master in the Robot, this is the most applicable way to controll a Fronius