Just received two weaver osgood bradley coaches in sealed boxes. Ran on my layout for about ten mins. Everything looked wonderful until all of a sudden I heard a pop and breaker on MTH DCS layout tripped. Isolated problem to one of coaches. Five mins later second coach blows. Attached pic shows result. Any ideas what caused. With boards removed no problems indicating short in frame like pinched wires etc
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Looks like old capacitors shorted and then overcurrent took out the diodes. Notice the capacitor is blown completely apart...
Thanks for reply. What causes over current was it result of capacitor blowing or did capacitors blow from over current in the first place ? In Any event I will replace with led so I will be looking into your led kits
Electrolytic capacitors loose their dielectric film with time if they’ve not been energized. They can sometimes be reformed with increasing the voltage in steps over a day or two. But, they are very conducive, and applying full voltage all at once will draw a high current and they usually bulge or explode from heating.
@Wvm posted:Thanks for reply. What causes over current was it result of capacitor blowing or did capacitors blow from over current in the first place ? In Any event I will replace with led so I will be looking into your led kits
Impossible to know for sure, but my guess is the cap died and the resultant short took out the diodes.
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