@mikep91 said in Duet 2 Wifi - Heater Fault - Sensor Short - 2000c:
We are running quite long cables for the PT100's but they are shielded.
Note that shielding on it's own may not help. Cable shielding only works if one end of the shielding is grounded. Grounding both ends can cause the shielding to transmit signals, and grounding neither end can cause reflections from the cable itself.
As for 2-wire vs 4-wire, see https://docs.duet3d.com/en/User_manual/Connecting_hardware/Temperature_connecting_PT100#wiring-the-pt100-temperature-sensor
2-wire connections have the advantage of wiring simplicity. 4-wire connections have the advantage of greater accuracy; the extra wires compensate for the resistance drop in the wires, making readings more accurate. 4-wire does not improve resistance to interference; better approaches to reduce noise include twisted wiring, isolation from noise sources, shielded wiring, better grounding of components etc.
Ian
