Are you using the same cord when switching power supplies? Short might be in cord.
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The LittleFuse 452-454 (Fuse F1) is just to the right of the power connectors but would not short the power supply on failure.
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If your power cord has an automotive lighter plug , some have a fuse located in the metal tip but again this wouldn't cause a short.
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I really think the cord is the prime suspect as the F1 fuse would prevent a shorted board from killing the power supply
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Good Luck
Brian
BrianH