In another post I mentioned that Ifound a problem with MTH's wiper screws.
Well I just discovered anotherproblem with the screws.
I was pushing my engines back and forth over the switches. I forgot to turn off the power.
As the engine went through the (turnout) switch. The fuse in the TIU blew.
When the screw crosses the moveable rail it shorts through the screw and a rail wiper. The not used moveable rail where the screw touched and the wiper is opposite polarity.
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