RS-485 App Note: Biasing Resistors

Sometimes it may be necessary to add biasing resistor to the RS-485 Modbus interface to make it work correctly with some sensors, for example ALMAG Flow Meter from SmartMeasurement). In such case, please add 470 MOhm resistor between A and VAUX or between B and GND as in the photos below. For further questions or clarifications, please contact Zenseio support.

These resistors can be readily be procured from here: https://www.amazon.com/gp/product/B08QRQRSJ1

Resistor between A and VAUX

Resistor between B and GND

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