I currently try to understand a new technology: Profibus, until now I worked with HART, with which I also had some struggle in the begging but now it's clear. I try to understand why in a factory is used both PA and DP. I understand that to convert a PA Profibus to DP a coupler is needed "...The connection of PROFIBUS PA subsegments to the RS-485 PROFIBUS DP segment is carried out using segment couplers or links. Segment couplers are transparent from the standpoint of the bus protocol...", but what I don't understand is why the PA is used? and not directly DP? (only for safety reasons? "... PROFIBUS PA can be deployed in hazardous environments since its physical layer: MBP, is intrinsically safe..." in this case what does it mean intrinsically safe?)
And what is the difference between these terms:
- PA (process automation)
- DP (decentralized periferics)
- MBP and RS485
I understand that MBP and RS485 are the communication protocols, but in this case what are PA and DP? Only a standard (e.g ISO)?