Dear Technical support,
I have connected the three sensors in daisy mode with the PT100 amplifier provided. The sensors are connected to the Arduino Mega with RAMPS 1.4 board. The sensors are connected to A3 - A5 - A11 with the GND used are the three taken from AUX1 and AUX2 blocks.
The sensor with higher temperature is always the one which supplies the 5V taken from AUX2.
The same appears during heating phase, but PID autotune is still not done.