level2:communication_between_2_webhmis_via_internet
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Communication between 2 or more WebHMIs via internet
Sometimes you need to have a connection between far systems, e.g. like in the following picture:
You might want to automatically control supply pumps depending on the water level in a far water tower or reservoir.
With the WebHMI and Level2 connectivity options it is done with ease:
Option 1. Using MQTT protocol
- Connect both WebHMIs to the Level2 IoT
- Subscribe the pump station WebHMI to the topic with level that far WebhMI publish onto the Level2 MQTT broker.
Option 2. VPN and Modbus TCP
- Connect both WebHMIs to Level2 and and remember remote node (reservoir side) IP address in the VPN network
- Turn On (Modbus TCP Server) on the water redervoir side
- Enable routing for pump side WebHMI to the remote peer node
- Create Modbus TCP connection on the pump side WebHMI using IP address from (1)
Option 1 Is preffered due to the nature of the MQTT protcol which saves traffice for communication while Modbus TCP will create constatn polling process.
level2/communication_between_2_webhmis_via_internet.1644329266.txt.gz ยท Last modified: 2022/02/08 14:07 by emozolyak