Modbus Plus Networking


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What is the difference between Modbus Plus Tap and Inline Connector and what is the difference between Modbus Plus terminator and Terminating Connector?
The MBPlus Inline Tap include the abilty to provide a inline connection point from the trunk cable to a drop connection. The trunk cable comes in and goes out and the drop cable (various lengths) goes to the drop device (node). The drop cable is actually a continuation of the "daisy chain". It has a pair of wires down and a pair of wires back up to the tap. There are 3 different models of Inline Taps: Standard, Ruggedized and SuperTap. These taps are usually mounted away from the drops.

The MBPlus Inline Connector is a simple "vampire style" connector (AS-MBKT-085)that connects the trunk cable directly to a device (node). There is no cable required between the inline connector and the drop. They attach directly to the node port.

Terminators are required because MBPlus is a "485 like" physical layer. Terminators can be part of the Inline Tap (jumper). Alternatively, there are inline connectors that include the termination resistor (AS-MBKT-185).

Refer to one of the Modbus Plus Manuals like the Planning and Installation Guide 890USE10000 manual.
If looking for a good Modbus Plus tap, consider using the Phoenix Contact din rail mount versions. They use screw terminals, have a switch selectable terminating resistor with a handy circuit for diagnositics of the network. They are available in a version with and without programming port. The pinout and functional components are designed to match the schneider taps. In my opinion the only way to go. Part numbers are 5603903 and 5602112 respectively.
Where I could get more information about how to interconect the Phoenix Contact Taps with a Modicon Quantum PLC (140NOM21200 card) and a Scada computer with a H16NHM30032 modbus plus card?