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For a few months now, I have been getting shocked when I touch anything powered by a DC power supply that is not case neutral.
The problem is so odd, I figured if I posted about it, no one would believe me, but my voltmeter shows it too.
The problem occurs when you touch the output of a DC power supply or anything that is case positive or negative. For example, touching the battery charger shown below, the frame of a car while it is charging, or the battery plugged into a UPS (makes it hard to unplug)
This isn't just a little shock though like you get from licking a 9v battery, this is a big shock, like when you touch 120 VAC (turns out it is). The severity of the shock seems to vary with the output current of the power supply, but the voltage seems to have no effect.
The odd thing is, things still work. Today, I was trying to change out the battery on my UPS, but I had to put rubber gloves on to unplug it, because I got an awful shock every time I touched one of the terminals. When voltmetered across the + and - of the SLA Battery, I get 14.3 volts.
The problem seems to go on and off. It may be that I just don't notice it (I don't use anything that would shock me), but I think I have been able to use the battery charger shown below without being shocked. I have not been able to find any sort of pattern between when I get shocked and other conditions.
Anyone have any ideas on this? I would really like to fix it.
The problem is so odd, I figured if I posted about it, no one would believe me, but my voltmeter shows it too.
The problem occurs when you touch the output of a DC power supply or anything that is case positive or negative. For example, touching the battery charger shown below, the frame of a car while it is charging, or the battery plugged into a UPS (makes it hard to unplug)
This isn't just a little shock though like you get from licking a 9v battery, this is a big shock, like when you touch 120 VAC (turns out it is). The severity of the shock seems to vary with the output current of the power supply, but the voltage seems to have no effect.
The odd thing is, things still work. Today, I was trying to change out the battery on my UPS, but I had to put rubber gloves on to unplug it, because I got an awful shock every time I touched one of the terminals. When voltmetered across the + and - of the SLA Battery, I get 14.3 volts.
The problem seems to go on and off. It may be that I just don't notice it (I don't use anything that would shock me), but I think I have been able to use the battery charger shown below without being shocked. I have not been able to find any sort of pattern between when I get shocked and other conditions.
Anyone have any ideas on this? I would really like to fix it.
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