Shocking USB passthrough
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Insane sir, does your body have a weird magnetic field? Like when you wear a watch does it stop working? If so might explain it... I have a strange relationship with electronics because of mine....
Insane and Fetasigma, it's absolutely plausible, and It's not the fault of the passthroughs -- it's the power supply!
The metal casing of the passthrough is wired to ground. This is normal and by design -- it wouldn't be able to make an electrical connection with the cartomizer otherwise.
This means that if the USB ground (one of the pins in the USB connector) is not actually truly ground, there will be a leakage current, and you can indeed get shocked from holding it -- probably not dangerous but very uncomfortable.
The question is -- What USB port are you plugging it into?
If the answer is a USB power adapter, then that would explain it -- they are usually not grounded. You COULD try flipping the USB power adapter in the socket and see if it helps. This will swap the Live and Neutral conductors, and there's only a 50% chance you got it right the first time.
If you're connecting it to a computer, make sure the computer is connected to properly grounded power outlet! Ground must be maintained all the way, including power strips, or it will not help. If you get shocked from touching the computer's metal parts while standing on the floor with your bare feet, the computer is not properly grounded. If properly grounded, this never happens.
I live in Thailand, and in a couple of houses where I've lived, I've encountered missing ground, or even ungrounded outlets. Touch the computer while standing on the bare floor = zap! The Thais solution to this would be to put a rug down under your feet. I preferred the more technical solution of pounding a copper rod into the ground outside and running the wire through the window, grounding my power strip and all my equipment. Crude, but correct, and it worked like a charm.
I had a very similar problem literally just days ago when connecting my chargers to a powered USB hub with its own (ungrounded) power supply. I got shocked when screwing in the batteries! The solution was to run a usb cable between the hub and the computer, which was already properly grounded, thus in the process grounding the hub and everything connected to it. Problem solved.
The metal casing of the passthrough is wired to ground. This is normal and by design -- it wouldn't be able to make an electrical connection with the cartomizer otherwise.
This means that if the USB ground (one of the pins in the USB connector) is not actually truly ground, there will be a leakage current, and you can indeed get shocked from holding it -- probably not dangerous but very uncomfortable.
The question is -- What USB port are you plugging it into?
If the answer is a USB power adapter, then that would explain it -- they are usually not grounded. You COULD try flipping the USB power adapter in the socket and see if it helps. This will swap the Live and Neutral conductors, and there's only a 50% chance you got it right the first time.
If you're connecting it to a computer, make sure the computer is connected to properly grounded power outlet! Ground must be maintained all the way, including power strips, or it will not help. If you get shocked from touching the computer's metal parts while standing on the floor with your bare feet, the computer is not properly grounded. If properly grounded, this never happens.
I live in Thailand, and in a couple of houses where I've lived, I've encountered missing ground, or even ungrounded outlets. Touch the computer while standing on the bare floor = zap! The Thais solution to this would be to put a rug down under your feet. I preferred the more technical solution of pounding a copper rod into the ground outside and running the wire through the window, grounding my power strip and all my equipment. Crude, but correct, and it worked like a charm.
I had a very similar problem literally just days ago when connecting my chargers to a powered USB hub with its own (ungrounded) power supply. I got shocked when screwing in the batteries! The solution was to run a usb cable between the hub and the computer, which was already properly grounded, thus in the process grounding the hub and everything connected to it. Problem solved.
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Thanks Leif, ya make a good point. My house was built in the 40's and not all of the outlets are grounded.
>> You COULD try flipping the USB power adapter in the socket and see if it helps.
POP! Goes the MOSFET.
Hardly a 50/50 chance since the USB plug is keyed.
Floating ground is a possibility.
POP! Goes the MOSFET.
Hardly a 50/50 chance since the USB plug is keyed.
Floating ground is a possibility.
my simple solution was just not to leave it on bare skin, anyways its kindof a fun tingling anyway not so much that it hurt just mildly annoying. mine occurs only when on bare skin and hookined into a usb wall converter
In the US, those are generally keyed too. Most any two prong device since the mid-80's would have a polarized plug, pesky fire code thing and all. Some ChinaJunk won't, though, since it hasn't gone through any safety certifications. I still wouldn't expect one to get bit unless the house has a floating ground. Grab a water pipe and something with a chassis ground and you'd find out pretty quick. I lived in a house built in the '20s that had knob-and-tube and a floating ground. The chicken-wire in the lathe-and-plaster walls was all floating about 80v. Used to bite me at the sink all the time. Eventually got annoyed enough to rewire the whole thing.
They used to think a piece of wax paper was adequate electrical insulation [shaking head]
They used to think a piece of wax paper was adequate electrical insulation [shaking head]
My V4L chargers have a keyed plug on their cable, but the plug on the other end is unkeyed, defeating that purpose. Besides, they don't have USB plugs anyway, the KR808D-1 screws right in.
My V2Cigs usb chargers are unkeyed, as is my generic KR808D-1 usb charger and my white cloud USB charger.
I haven't tested this myself, but wouldn't plugging it in the "wrong" way around vs the correct way, change the floating ground level? I don't understand why the house ground would factor into it at all, considering they're 2-prong plugs, without ground.
I lived in the states for 8 years -- indeed most 2-prong plugs sold there are keyed. However, e-cigs are usually made in china
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Wax paper, yeah, that was nice. Then again, tobacco cigarettes were safe too back then. Man they had it so easy.
My V2Cigs usb chargers are unkeyed, as is my generic KR808D-1 usb charger and my white cloud USB charger.
I haven't tested this myself, but wouldn't plugging it in the "wrong" way around vs the correct way, change the floating ground level? I don't understand why the house ground would factor into it at all, considering they're 2-prong plugs, without ground.
I lived in the states for 8 years -- indeed most 2-prong plugs sold there are keyed. However, e-cigs are usually made in china
.Wax paper, yeah, that was nice
. Then again, tobacco cigarettes were safe too back then. Man they had it so easy.
TT, TN, IT earthing systems - all in use in the US per NEC at some point or another.
Generally you'll see exposed-conductive to neutral as a 2-wire earthing system in the US, hence the critical nature of polarization.
In theory, Customs should whack non-polarized AC devices, or at least require a great big "Will Probably Kill You" sticker on 'em. Considering they'd be lucky to stop a trillion tons of fissile material coming in at once, YMMV.
Generally you'll see exposed-conductive to neutral as a 2-wire earthing system in the US, hence the critical nature of polarization.
In theory, Customs should whack non-polarized AC devices, or at least require a great big "Will Probably Kill You" sticker on 'em.
Considering they'd be lucky to stop a trillion tons of fissile material coming in at once, YMMV. 
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