pic: How we cool our compressor

[Doug G]

Originally Posted by eshteyn

Also electricity is the flow of electrons, which are negatively charged. They flow from positive to negative, and since the black wire is the negative thats why it melts.

I can't help myself... There's a couple of things about this statement that bothers me and so I felt a teaching moment coming on ...

1) Electrons absolutely flow; but from negative to positive. Unfortunately the definition of "current" is the flow of positive charge (even though no positive charge carriers are flowing in these circuits, thank those dudes from the 1800's for defining current before they knew the existance of electrons), and thus we say current flows from positive to negative. This is a commonly misused/misunderstood concept. 2) The current in the black wire is no different than the current in the red wire and no different than the current in the motor windings inside the compressor. It is a series circuit (red wire --> Compressor --> black wire) and thus the current flow must be the same everywhere (conservation of charge). Perhaps the black wire melts first because it's insulation can't stand the heat and/or it is a higher AWG than the red wire resulting in more heating (I^2*R)?