Chapter 5: Communications; Rs232 - Unitronics Vision 120 OPLC User Manual

Chapter 5: Communications

This chapter contains guidelines for communications connections. The controller has 2
RJ-11-type serial communication ports. Each port can be adapted to either the RS232 or
RS485 standard, via jumpers located within the controller and the appropriate VisiLogic
program settings.
CANbus-ready models also offer a CANbus port.
Caution

RS232

Via RS232, you can:
•
Download programs from a PC.
•
Communicate with external devices.
You can, for example, use your PC to access a networked controller via its RS232 port.
You can then view, read, and write data into any unit. RS232 also allows you to view
the network via a SCADA program.
•
Turn off power before making communications
connections.
•
Do not connect the controller directly to a telephone or
telephone line.
•
The RJ-11 type serial ports are not isolated; note that
communication signals are related to the controller's 0V;
this is the same 0V used by the power supply.
•
Ports must always be used with an appropriate adapter.
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