1 PT100 at 2 MAX31865

[gisesp32]

Hello,

I have maybe a very easy to answer question.
Can I use 2 different Max31865 with one PT100 (safety reasons).

Configuration

1 Esp32 with Max31865
1 ESP8266 with a second MAX31865
They are totally separated with the exception of serial pins for communication.
Even with only one common power supply I can’t get them work. If I unpower one of the Max devices the other one works fine.
I got no fault detection at both of them

So it seems it depends on having 1 PT100 for 2 different Max 31865.

Thanks in advance for an answer

Cheers

[adafruit_support_bill]

That won't work. The chip works by driving a known current through the RTD and measuring the voltage drop to determine the resistance from which the temperature can be derived.

With two chips attempting to drive current through the same device, all bets are off.

[gisesp32]

Thanls for that fast answer... I'm looking for another solution...