Proof of concept about reading registers from modbus device into a browser with websockets.
Simple nodejs project with two dependencies:
- modbus-serial
- websocket
Comes with HTML file to read the values from websocket (charts based on Smoothie Charts).
The server reads the same 3 registers each second and broadcast it to all clients.
First: npm install
, then...
Two modes are available: connected or faked (debug/offline mode).
node index.js <host> <slave_id>
Establish a TCP connection and read the register 40150, 40151, 40152 (based on Schneider Electric ION 7650 register map). Respectively Ia, Ib, Ic.
node index.js debug
Fake a ModBus provider and throw random values.
Open index.html
in a browser (tested with Firefox and Chrome) and look at the values.