Zapped by 14.5μF capacitor charged to 240V RMS!

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Long story short, the other day I unwired the controller from a small mains hoist as it was being temperamental. I had already ruled out the the limit switches on the hoist it's self.

Today I went to look at the controller and thus ran some basic continuity tests on the controller and the short piece of 4 core cable attached to it that I disconnected the other day. I simply held my test probes of my continuity tester against two of the four wires from the controller and then pressed the controllers UP button.

The next thing I know I felt this sharp zap in my fingers and let go of my test probes. :eek::notworthy:

Turned out that inside the controller there is a 450v 14.5μF capacitor across the dual pole rocker switch's "Up" direction and a 450v 3.5μF capacitor across the dual pole rocker switch's down direction. I have since discharged both capacitors.

Oh well, at least I now know what's inside the controller, I was going to open it up eventually anyway.

Regards: eveares.
 
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