I am trying to use the PLC5 MSG command to pass power monitoring information from an Allen Bradley Power Monitor 3000. Since the native port for the PowerMonitor is RS485, I have to use an RS485 to RS232 coonverter..AB Eng OOPS! Has anyone had to work this little fiasco out?

 

I don't see any problem with the system you describe.

I would by instinct use a 1761-NET-AIC RS-232/485 signal converter, but the PLC-5 serial port should be selectable for RS-485 signaling itself. I would be more comfortable with the NET-AIC.

The PLC-5 Channel 0 serial port is configurable for DF1 Half Duplex Master mode, and the PowerMonitor 3000 serial port is hard-set for DF1 Half Duplex Slave.

The PowerMonitor emulates PLC/SLC data tables, which are well documented in the PowerMonitor user manual.

Do you have a specific problem that you need help with, or are you more generally asking if the two devices can communicate ?

 

Thanks for the reply Ken. I don't usually use this forum for support and most of the time I get good support from Rockwell, but in this case I have the finger pointing and very few details.

My PLC5 Ch 0 does RS232, RS423, and RS422A. Not RS485. I do have an Aten IC-485S RS232 to RS485 converter to do the protocol conversion.

The Power Monitor instruction manual Pub 1404-IN007D-EN-P has no PLC5 MSG ladder examples or samples of ASCII strings. Details would be helpful if anyone has them.