RS 485 on Vision 570

[Ico747]

Sorry the title should be RS 485 on Vision 570!!

According to the specs RS485 port (Port 1 or 2) are electricaly insulated. According to the RS485 recomendations I should connect sygnal ground of all devices on a multy drop network. Where is the sygnal ground of Port1 (or Port2) when set as RS485?

[Walkerok]

I'm not sure I am understanding the question correctly, but PIn 6 is the - and Pin 1 is the + of your two wire RS485 communications ports. All + communications connections for all of the devices on the multidrop network are on the same line and all of the - communications connections ar on the other line. If you look at the help file in Visilogic (search for "multi drop" there is a pictorial of the connection under "Network Topology and Wiring").

Keith

[Ico747]

I'm not sure I am understanding the question correctly, but PIn 6 is the - and Pin 1 is the + of your two wire RS485 communications ports. All + communications connections for all of the devices on the multidrop network are on the same line and all of the - communications connections ar on the other line. If you look at the help file in Visilogic (search for "multi drop" there is a pictorial of the connection under "Network Topology and Wiring").

Keith

If you configure Port1(or Port2) as RS232 pin 2 and 5 are "0 volt reference". I am missing such "0 volt reference" in the case when the port is configured as RS 485.

[Emil]

If the port is isolated, like in your case (V570), you don't need to connect 0V referrence. In case the port is not isolated, 0V refference is 0V of 24V power supply you use to supply the controller.