DH485 with Rs232 problem

i have a communication problem with four SLC 5/3 connected to each other by DH485 and with PC through converter by RS232
but i want to get the data from the four PLCs without changing the SCADA[INTouch]-which is a local one- over the internet to a remote location so i can setup new SCADA[ClearScada] for monitoring only without control

what can i do?

Get another DH485 to RS232 converter for, or put a DH485 compatible RS-485 port in the new SCADA PC and hang it on the DH485 network.

Or bridge through the existing SCADA (if possible). If the existing SCADA is using RSLinx Gateway for communication to the DH485 network, then you should be able to connect the two SCADA machines and share that driver using the RSLinx driver called "Remote Devices via Linx Gateway"

I agree that the simplest thing would be to upgrade the existing PC license to RSLinx Classic Gateway and connect it using a VPN across the Internet.

This might not be practical due to nontechnical reasons of security or responsibility.

My recommendation is to use the 1747-UIC USB to DH485 converter on the second PC, along with RSLinx Classic Gateway.

I do not recommend a 1761-NET-AIC or 1747-PIC device because of the stability and setup problems with the old "1747-PIC/AIC+" driver in Windows NT/2000/XP/Vista/Seven.