What is the correct configuration for 3-wire RTDs connected to an ADAM 6015 module?
The user manual shows:


On the RTD the two wires that go to COM and RTD0- should be the same color, and their order of connection doesn't matter, as you can see from the drawing, they are in parallel.

This is a sort of Kelvin connection, like the 4 wire type, but less expensive and still good enough for most RTD resolution.