On Line Tutorial Class

[nerf]

Originally Posted by kalc

Hi Nerf,
I have half a mind to do a usb PT mod, but in this regard i hav a question.
In the mod u hav shown, what happens if the atomiser shorts out?
Normally do all adaptors have current limiting inbuilt?

I don't see how the atomizer would short out on the OEM connector, you're not going to over-tighten it and bypass the silicon insulator, and even if you did most USB hubs are going to have built-in protection. My laptop will shut down the port if it senses too large of a current draw, for example.

As for the built-in current limiting, some passthroughs have a battery in-line, and their design is such that you're not actually using your USB port to do anything except keep the battery charged, you are simply vaping off of battery power.

That being said, I have one of those P/Ts in front of me right now that someone sent to me so I could use the connector to make them one that worked, and as far as I can gather looking at the PCB, it has nothing protecting the battery in the event of a short and uses an unprotected 10440 li-ion 360ma battery. If anything, this would be even more dangerous as a short could cause your battery to discharge at an extremely high rate and explode.

As with everything else in life, use your best judgement based on the best information you have available, if you're worried about a short harming your computer, research the specs on your motherboard or call the manufacturer and ask them.

[kalc]

Hi Nerf,
Yes, i completely agree that it would be even more dangerous with a battery right in front of ones face.
Normally when an atomiser malfunctions, one would expect it to become open circuit, but somewhere in a post i was reading that someone measured a short with a multimeter wit one of his defunct atomisers.
In ur experience with these things, hav u or someone else ever observed a short circuited aomiser when it stopped funtioning?
In my laptop too i hav seen the same feature(by accident though), but i am not sure abt my desktop(havent shorted the usb yet).
The other option is to use the usb adaptors, but since they are so cheap, i am afraid they dont hav any current limit mechanism, which means that the secondary coil will most probably get damaged in case of a SC.
My point is, what abt an LDO with a current limit of somewhere around 1.5A to 2A in the passthrough? Hav u considered such an option?
U might hav a customer here

[nerf]

Originally Posted by kalc

Hi Nerf,
Yes, i completely agree that it would be even more dangerous with a battery right in front of ones face.
Normally when an atomiser malfunctions, one would expect it to become open circuit, but somewhere in a post i was reading that someone measured a short with a multimeter wit one of his defunct atomisers.
In ur experience with these things, hav u or someone else ever observed a short circuited aomiser when it stopped funtioning?
In my laptop too i hav seen the same feature(by accident though), but i am not sure abt my desktop(havent shorted the usb yet).
The other option is to use the usb adaptors, but since they are so cheap, i am afraid they dont hav any current limit mechanism, which means that the secondary coil will most probably get damaged in case of a SC.
My point is, what abt an LDO with a current limit of somewhere around 1.5A to 2A in the passthrough? Hav u considered such an option?
U might hav a customer here

Kalc,

I just don't really see the need in passthrus, shorts are rare and discovered quickly enough that even if the USB power source you're using doesn't have any form of current limiting, damage should be nil. Shorting out a $2 USB hub for 2-3 seconds shouldn't cause any long term damage to it, and thats as long as you're going to keep that button pressed without getting any vapor.

Adding an LDO would simply complicate construction and raise the cost.

[kalc]

Ok nerf,
thanks for clarifying.