RS485 Tips For MODBUS/RTU & DF1 Networks

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The EtherMeter contains an RS485 port for Modbus/RTU and DF1 communications in multi-drop applications. When using the RS485 port, the following EtherMeter terminals are used: 19  –  RS485A (-) 20  –  RS485B (+) 21  –  Signal GND Reference (contains current-limiting resistor) In order to use RS485, attention should be given to the EtherMeter’s dip switch positions: Latest EtherMeter: … Read More →

Serial Snooper Utility

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Over at control.com, a PLC engineer was working to troubleshoot the connection between two PLC’s. Having done this way back when, I decided to post what I think was a pretty nifty solution. (Besides, this could be useful for troubleshooting communications between any two pieces of computer equipment, including an EtherMeter.) In my case, I had both a master … Read More →