Four short scenes: the gateway polls your field devices, sends each reading to two servers that can be different platforms on different protocols, lets your SCADA read the devices straight through, and fails over from Ethernet to 4G without losing a reading.
Step 1 of 4
WT460M is the Modbus master. It polls each field device on the RS-485 bus, one after another, and keeps the answers in its register table.
Polled data: reads, values, eventsTransparent Modbus framesTLS on the server link (a padlock on the data)