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PROFIBUS is an extremely flexible and reliable communication technology, however, likeall high-speed digital communications systems, problems can be caused by a number ofsimple errors. Poor wiring and layout can cause pickup or interference in cables givingcorrupted telegrams. Incorrect termination and many other errors can cause reflections tooccur in fieldbus cables, resulting in distorted and corrupted telegrams. In order tounderstand how to avoid some of these problems we must first understand how they occur
RS-485 is a balanced two-wire transmission system, which means that it is the“differential” or difference in voltage between the two wires that carries the informationrather than the voltage relative to ground or earth. Balanced transmission is much lesssensitive to pickup and interference than single-ended or unbalanced transmission. Let ussee why.
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Hello , I am not sure but both are used for high rate of data transmission and I think PROFIBUS is faster while RS-485 works better when it comes to high distances (this needs verification from your side Maher because I am not sure about it and please don't take my reply for granted!).
I have a PROFIBUS -DP cartridge in my CNC machine, a year ago, it used to give me occasional errors causing the machine to stop in the middle of operation, just like what happens when you press the red mushrum emergency button . In my machnem the PROFIBUS is in charge of tool change and related operations.
At the end, the machine supplier sent me a technician to fix it and we changed the profibus hub after checking each wire contact (it's a link that looks like wi-fi router and connects to aother terminal/battery that gathers input data). When I asked the service guy about it, he told me it's the fastest communicaton means in automation industry and is usually reliable for such applications (machining centers, CNC machines ..etc and usually suggested by the controller manufacturer).
This is all I know about it so you have to double check my information with a specialist.
Attached a photo of what I have:
