There is the official document "Modicon. Modbus Protocol Reference Guide (PI–MBUS–300 Rev.J)" currently in use. And to my very curiosity is that WHAT does the PI here stands for? This confuses me for years.

 

> WHAT does the PI here stands for? This confuses me for years.

Maybe Protocol Illumination.

 

Hello,

I have the original Gould specification from 1969 and it is not used. The oldest document I have it on is the Gould manual revision B.

There are three manuals that use the same PI-MBUS prefix and they are all for "Programming Protocol".

So there is more data but, no answer. Finding the person that created the designation would be...

Good luck,

Mark
http://www.peakhmi.com/

 

> WHAT does the PI here stands for? This confuses me for years.

I have been in the understanding that "PI" here stands for:
"Profibus International" YMMV

 

> I have been in the understanding that "PI" here stands for:
> "Profibus International" YMMV

Thanks BUT, does Profibus equate Modbus... I only know Modbus -_-

 

While not a firm answer, my recollection is "Programming Instruction"

William (Bill) L. Mostia, Jr. PE
ISA Fellow, SIS-TECH Fellow,
FS Eng. (TUV Rheinland)
SIS-TECH Solutions, LP

Any information is provided on Caveat Emptor basis.

 

In my experience PI has always stood for "Process Instrumentation" but I have never heard it used that way in the context of this thread.