Re: Resistance Leak from Fast Track turnouts
A very,very high resistant short circuit.
Not enough current flow to trip any circuit protection, but enough current to heat the circuit over time and cause damage.
I have had leakage through a grain of ballast from the bottom foil to the top foil of a PC tie. Over time (several years on a club layout) the small amount of heat destroyed the resin until the foils touched. Then it took a while to find the now significant short that was tripping the circuit protection. The area became apparent when a heavy loco was in the same place when the “short” occurred.
Another one was a Walthers passenger truck with one wheelset across the gaps at the end of a reversing block. In a much shorter time than above, the wheel softened enough to move on the axle causing a derailment. But did not trip the auto reverser.
Both cases there was a very high resistance short, just a tiny leak of current.
I’m sure many can relate to the term resistance leak.
I avoid the use of double sided PC ties, to the extent I heat & peal the the one foil off the tie before building the turnout. I usually do the pealing before cutting the ties to length.