I am implementing a control system in Node Red that uses PT100 RTD temperature values from the RTD Data Acquisition board to drive power on/off decisions for some equipment. Power control will be via the 3 40A 240V Relay Hat. If I read the board correctly during wiring, I have the two "blue" connectors on the resistor symbol posts (center and right); and the "red" connector on the left-hand posts of Sensor 1 on Board 0.
When I read the PT100 with the Output Sensor Resistance box checked, I get values in the 0.0048 to 0.0052 range that, presumably, reflect ambient temperature in the room where RPi is located. When I uncheck the Resistance box, I assume from reading the docs and the node configuration panel that the payload value should be ambient temperature in C. I consistently get -259.xxxx, which I am certain is below ambient temperature in my office! :)
Thoughts on what I'm doing wrong?
