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[Oubadah]

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[thiggins]

Of course there is only 12v and a few watts going into this switch, so I'm not worried about it hurting me, but I don't want it to hurt it'self. I can feel quite a sharp, constant sting if I touch the back of my hand to the casing.

Surely this isn't normal? Why would the case be live?

Could be that something else may have a power supply fault.

Unplug all data cables from it and try your test again. Get a cheap voltmeter or even a neon-bulb tester instead of using your hand. You aren't feeling 12V. You are feeling line voltage...

 

[thiggins]

It happens whaen nothing but the power lead is connected.

Are you talking about a digital multi-meter? What do I measure to?

Use a voltmeter, digital multimeter set to AC volts.
Touch one lead to exposed (not painted) metal on the case. The other to AC mains ground.

If you see AC voltage, you have a bad power supply.

 

[thiggins]

Yeah, I get ~90V between the casing and ground. I guess I'll send the lot back (HP can replace the switch too, on the off chance it was damaged by the power supply).

I think that because you are feeling a tingling that you aren't seeing "phantom" voltage. To be sure, switch the meter to ammeter mode and start on a high range, then step down to see how much current is flowing.