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Yokogawa CS3000 VNET Connection Problem
I am trying to learn a new system (for me) in a lab. A "red cross" is shown on Vnet icon on my computer.

I am not getting a connection to my Controller.

I am using FFCS (AFF50D), with coupler (AIP504) and VF702 card (VNET) with 10base2 cable and a termination resistor (50 Ohms on Coupler). I am using only one connection of Vnet card i.e BUS1.

Hardware Config:
I connected a 10B2 cable from VNet card bus1 to bus1 side of my coupler unit and also installed a termination resistor there. I am also not using my BUS2 of the coupler (hence at DSBL position). From bus1 side of the coupler unit, I have 2 Ethernet cables which are connected to right and left BUS1 side of my processor module. Further, I have not installed any sort of I/O modules on my controller at this point. [ all of the dip switches are carefully configured i.e on processor and vnet card]

Software Config:
I am using windows XP. I have successfully installed VNET/VLNET driver release of 2009 ( which is visible on windows device manager utility also). As i want my PC to be an Engineering workstation, therefor i used IP: on vnet with subnet: . (controller IP:
The Vnet icon on my taskbar shows a "red cross" on it which means that connection is not through.

If u have any suggestion for solution , please feel free to reply.

I will be much obliged if u could send solution to "" too.


A T-type connector with one end terminated with a 50Ohm resistor while the other end connected to the V-net card on your PC and the third end connected to the PLC. Sometimes the terminator is loose, so try to adjust your terminator a little bit. When using Duplex controller, use a dual redundant bus (even for lab testing). When your controller is connected, and you get a healthy connection on V-net icon in windows tray, perform an offline download to the controller (if you get "failed to obtain password" error while starting a target test).

I am only receiving "failed to equalize database to HIS0264" error, which when figured out, I will share with you guys. In the meantime if you have any suggestion, please do let me know.