Shorted Reed Switch

[1BrickShort]

I have a reed switch that has been working properly for multiple cycles, then out of the blue it is showing a short circuit. The reed switch itself has been soldered to a circuit board and embeded in epoxy, so I do not have the luxury of being able to physically touch the switch or board.

Has anyone seen an effect on a reed switch that would cause it to suddenly short for no good reason, then remain shorted indefinetly even though there was no magentic field present?

Is it possible for a voltage spike to cause this? What else could cause this effect?

Does anyone have an idea as to what this could be?

1BrickShort

 

[patprimmer]

Umm

Maybe a metal part inside the switch broke or came loose due to fatigue, wear or a voltage spike and now bridges the contacts in the switch, or a spring failed allowing the contacts to permanently become grounded.

Regards

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[1BrickShort]

Well, you guys were right! I found a faulty potentiometer in the circuit that was sending current spikes down the line...thus welding the paddles in the reed switch together.

Thanks for the input

1BrickShort