USB passthrough help

[NotoriousJoe]

Not sure if this is the right form. Sorry if it is.but Anyways , I made USB passthrough. I get 5.14 volts when the button is pressed. Problem is when I put the atomizer on it drops to 1.37 volts. Any idea why this is happening, and how I can fix it?

 

[the86d]

Is it a cheap china usb hub, or wallplug adapter?

 

[NotoriousJoe]

I just used an old xbox 360 plug and play cable. But I have it plugged into a USB adapter from my iPhone. Also plugged it into my laptop as well and I get the same results.

 

[Dalton63841]

Probably restricting current to 500mA.
I=V/R

V(Voltage)=I(Current)*R(Resistance)
V=.5Amps * 2.8Ohms
V=1.4

Obviously there are slight variations depending on other factors, but the math fits. BOTH your laptop and the iPhone charger limit current to 500mA to protect the motherboard/logicboard.

 

[AttyPops]

Yeah, ditto. Get a 2.0 amp or higher wall wart and try again. Voltage suffers when amps are insufficient. I assume you have a 3.0 ohm atty or thereabouts. If so, you'd need about 1.6666 amps.

Ohm's Law Calculator

 

[NotoriousJoe]

Well I thought it seemed to simple. Lol. So I have a lot of wall warts lying around somewhere. But my passthrough I made is a USB. Do they have a wall wart that the USB plugs into? Sorry for all the questions. I'm new to this.

 

[Dalton63841]

As a general rule of thumb I believe you want something ~2.5A, btw this is also why they suggest not plugging a passthrough directly into your computer, because of its high current requirement.

 

[AttyPops]

2.0 amp will work with 3.0ish ohm atties. The more robust, the better. However, even 2.0 amps at 5 volts (USB voltage) is 10 watts. Generally most vape around 8 watts. It all really depends on the atty ohms and wire resistance. Generally, a more robust part will last longer, however many people use the 2.0 amp ones. I've had one for 6 months or more now and it is fine. Meh.

2 amp AC to USB Adapter, ideal for Passthroughs

 

[NotoriousJoe]

Thanks guys. I'll have to check out the amps on the plugs I have. Surely that sounds like my problem. Haven't heard that you shouldnt plug it directly into a computer. I watched a YouTube video and just jumped right in without doing any research.

 

[Dalton63841]

Haven't heard that you shouldnt plug it directly into a computer.

For the record I haven't had an issue with this, but there are war stories about this on here...Apparently not all limit the current, and too many amps getting pulled through onboard usb = poof. Most suggest a powered usb hub.

 

[AttyPops]

Yeah, what they don't tell you on youtube could fill a book. lol. Basically, for others reading this too, there are two types of PTs... battery powered 3.x volt, and a "direct" 5 volt PT (no battery). The ones we are discussing here are the 5 volt ones that need the amps.

The other type, with an in-line battery, are fine to plug into a computer since they just trickle charge the battery and only draw around 400 mA (.4 amps). This includes the eGo PTs and the like. That USB adapter you were using would have worked for those too. Just not for the 5v direct PTs.

There's a lot of discussion on PTs and computer USB ports. Dalton63841 is correct... just use the wall wart. It's often less than $10.00, frees up a USB port on your computer, and if there is a short......or it stresses the port..... it's a lot cheaper to replace than a mobo (fixing a usb port, if even possible, is almost as expensive as a new mobo). Some people insist on using 5v PTs with laptops to have portable power, but I'd either use a 3.x volt PT or get other portable power and use the computer battery for computing. 2 cents

 

[Dalton63841]

Yeah, what they don't tell you on youtube could fill a book. lol. Basically, for others reading this too, there are two types of PTs... battery powered 3.x volt, and a "direct" 5 volt PT (no battery). The ones we are discussing here are the 5 volt ones that need the amps. The other type, with an in-line battery, are fine to plug into a computer since they just trickle charge the battery and only draw around 400 mA (.4 amps). This includes the eGo PTs and the like.

Well hey look at that. I just learned something new from this thread. Is there an easy way to know which type of passthrough you are getting? I'd love to get a battery powered passthrough. Im pretty sure mine is direct, as you can't vape on it the moment its unplugged. I would assume battery powered could vape for a bit unplugged.

 

[AttyPops]

Well hey look at that. I just learned something new from this thread. Is there an easy way to know which type of passthrough you are getting? I'd love to get a battery powered passthrough. Im pretty sure mine is direct, as you can't vape on it the moment its unplugged. I would assume battery powered could vape for a bit unplugged.

They have a battery box in-line on the USB cable, or an eGo battery (or some such) that has a USB connection on the end. And yes, you can vape em unplugged. Sit-n-go is one type. They have eGo style ones too. They usually tell what voltage. Of course, it is complicated with the mod market where you could get a 5 v mod with a built-in charger and USB recharge cable.... but I digress. I don't really consider them passthroughts in the sense of the term.

Basically 3.7/3.x volts is going to be a battery, 5 volts a direct... as a general rule.... not counting "mods" and other rechargeable e-cig gadgets. Since you did the math above, I'm sure you know your voltage so you can extrapolate to the type. And then change atomizers... one set for 5 v, one set for 3.x v Or just stay at 3.x Of course, once you go 5v, you never go back...........

P.S. And the above "fine for computer USB 3.x volt battery PTs" discounts shorts, malfunctions that could fry stuff...... just say'n.

 

[Dalton63841]

Of course, once you go 5v, you never go back...........

Thanks for the info. LOL I know I made a copper mod last week, it was 6 volts and I was blown away! It made some flavors a bit harsh, but I was thinking...5v would probably be perfect...In any case I am ordering a VV kit for my next mod, so I can switch depending on what I'm vaping/what atty I'm using. At the moment Im sitting here with a 3.7V mod, and eh...

 

[NotoriousJoe]

Wow I learned a lot from this. Thanks so much guys. This is off topic I think but next week I'm ordering the 3.7 boxmod ( if I can find any ) madvapes are out , do you have any suggestions where I could pick one up? I'm thinking about ecigmods.com for the simple fact that they are only about 2 hours away from where I live. So shipping should be quick.

 

[AttyPops]

Wow I learned a lot from this. Thanks so much guys. This is off topic I think but next week I'm ordering the 3.7 boxmod ( if I can find any ) madvapes are out , do you have any suggestions where I could pick one up? I'm thinking about ecigmods.com for the simple fact that they are only about 2 hours away from where I live. So shipping should be quick.

Go ahead and try em. IDK. Or one example:
Black 2xAA Battery Box with On/Off Switch,Style 2
510 Battery Connector, Sealed
Horn style switch -- Black
3mm Blue LED

+ batteries and charger of choice. The MV LED usually comes with a resistor. Use a heat-clamp when you solder the button, or make real sure you don't over heat it. Radio Shack also sells most of these parts, but not the atty connector nor the proper batteries, so you may as well get em all in one order. Get the protected batteries. Lots of reading on this forum for opinions on 14500 batteries.

The radio-shack buttons aren't too bad if you have issues. Try to find 3.0 amp buttons. Suggest at least 2 batteries so you can have one charging while using the other. Check threads for epoxy or hot glue while waiting for your order. You'll also need drill bits, solder, soldering iron, etc.

 

[twgbonehead]

My guess is that it's the cable, not the USB interface. I liked the small, flexible cables, but when I measured their resistance, it was often 5 ohms or more. It wasn't a problem with the USB port supplying the power (have vaped off my laptop, and my nephews' WII USB ports without any problem). But you need a heavy-duty USB cable, the thin ones just have too high a resistance.

BTW, "Mommy, Uncle Jim's smoking the WII" is a phrase I never thought I'd hear in my lifetime! (Particularly since my name isn't Jim, I changed it to protect the guilty...)

Edit:

I've also used my handmade passthrus with cigarette-lighter USB adapters (For the car). Some work, some don't (some can't supply enough power). When they work, they're fantastic! (5V is a great voltage!) But also, the USB Connectors aren't really designed to handle the current; I weaned myself off of USB Passthrus because they kept dying on me (seems like the connector burns out; vaping an LR cart on 5V. ) Also, most juices taste better to me at 3.7 than at 5V, but that might just be me and/or my juice or cartos.