Backwards compatibility and legacy interfacing

This interface is supported on the PGC5000 Direct Modbus

TCP from the VistaGateway Modbus Client application, and

OPC server application. If you use a VistaGateway, you only

have to write to one set of registers or OPC tag. If you are

writing direct to the PGC5000 then you must write to each

PGC5000’s Modbus interface because each PGC5000 acts

as a Modbus slave.

If you have legacy instruments (such as the model 3100 or

PGC2000 Series) then you must use a VistaGateway or a

Modbus enabled router. However, the Modbus enabled router

does not support the PGC5000 but you can write through the

Modbus enabled router to the PGC5000 using the Ethernet

switch with the PGC5000 being the actual Modbus slave.