The VW3A1101 HMI terminal requires supply from Altivar. When you connect HMI directly to Altivar, it is supplied from that drive.
But modbus T-junction box VW3A8306 is manufactured in a way that prevents connection of two different sources of DC supply. Internal 10V from one Altivar cannot be connected with internal 10V of second Altivar. From this reason, modbus T-junction does not provide link for supply signal between its free end (RJ45 plug) and any of RJ45 sockets. However, on RJ45 socket, each pin is connected to the same pin on the second RJ45 socket, including the supply signal.

Modbus T-junction box:
- links all the pins between two RJ45 sockets.
- only modbus signals are linked between RJ45 plug and RJ45 sockets.

VW3A1101 cannot be connected to RJ45 plug, because it will not work (no supply). VW3A1101 can be connected to RJ45 socket, either blue or red. Then VW3A1101 is supplied from that drive that is connected to VW3A1101 RJ45 socket, blue or red. As soon as that drive is switched off, VW3A1101 goes off as well despite the fact that there might be another drive on RJ45 plug.

Next, on HMI it is possible to select the drive to which HMI is connected to. Only one drive at time. Important is to select different modbus addresses on the drives. See attached video how to connect HMI to them.

Released for: Schneider Electric Saudi Arabia