We've already linked Jeffrey's ol thread where he tested it, in a somewhat scientific way. His first one melted in 2 hours, but was questionable before putting it to the test, so he tried another one and it went nearly 8 hours, just sitting there. Running a loco back and forth on a 3 foot test track is NOT going to hurt the motor, period. Unless it is a coreless motor, in which case the lifew will be measured in seconds - as it would with an old DCC decoder that doesn;t do high frequency drive.
--Randy
Modeling the Reading Railroad in the 1950's
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