Charging Query (AC adapters)

[makeyourself]

I am just wondering about power sources for eGo chargers and batteries. I have a Spinner which is charged in the standard way via the 510 connection connected to a charger, in turn connected to an AC adapter / USB port. I also have an iTaste VV V3 which is a passthrough and as such is obviously connected directly to an AC adapter / USB port via a micro-USB lead.

Now as I understand it I should be able to use any AC adapter for the Spinner regardless of its current output provided that it outputs 5V. What I am less sure of is the iTaste as this is connected directly to the power source, not via a charger. I know that the iTaste VV charges to a maximum of 4.2V and a USB port outputs 5V so the device itself must modulate the voltage and possibly the current input to obtain a 4.2V charging "output" from the 5V input. But I'm not sure of the exact details, so my question is could I safely connect the iTaste to say a 5V 2A AC adapter? In fact could this actually be a good thing because its a passthrough? The device won't work as a passthrough off of a 500mA power source when its completely dead so if I make available more current than it needs to charge then maybe it would.

I must say that I think its quite poor that even many reputable manufacturers fail to provide full technical specifications (charge rate for instance) and detailed instructions for their batteries. The iTaste's manual merely states "Plug the USB cable into iTaste VV ’s charging port and a power source". I doubt that plugging it into ANY power source would be OK or safe, for instance plugging it into an adapter with a voltage output far higher than 5V.

 

[mobocracy]

The USB standard is 5v @ 500mA. AFAIK, Apple introduced a non-standard signalling method a device could use to tell their USB adapters it could accept more than 500mA -- I think this was done for the iPad and hence the array of USB chargers that now offer 2.1A output.

But, the device has to be able to offer this signal to the charger, otherwise it only gets 500mA. The iTaste probably doesn't do this, so the extra power wouldn't be available.

 

[WarHawk-AVG]

Just remember, not all wall warts are built alike

Ken Shirriff's blog: A dozen USB chargers in the lab: Apple is very good, but not quite the best

 

[makeyourself]

The USB standard is 5v @ 500mA. AFAIK, Apple introduced a non-standard signalling method a device could use to tell their USB adapters it could accept more than 500mA -- I think this was done for the iPad and hence the array of USB chargers that now offer 2.1A output.

But, the device has to be able to offer this signal to the charger, otherwise it only gets 500mA. The iTaste probably doesn't do this, so the extra power wouldn't be available.

You're probably right but without knowing for sure I think I'll play it on the safe side, there are other devices out there, Samsung products for instance, that far exceed the 500mA USB 2.0 spec, I'm not sure whether they use the same signalling check or just go ahead and draw the power. Ultimately, there has to be some modulation of the power going into the iTaste which leads me to highly suspect that it only draws the amount of current that it needs to correctly charge the battery. But without manufacturer data sheet's or at least better instructions there's no way of telling for sure.

Just remember, not all wall warts are built alike

Ken Shirriff's blog: A dozen USB chargers in the lab: Apple is very good, but not quite the best

Yeah that's why I wanted to use an AC adapter that had a higher output than 0.5A. Many of the eGo chargers and mains adapters on the online stores appear to be of the cheap "no name" variety. The plastic earth terminal of the AC adapter that I bought from one supplier ripped off and jammed in the plug socket, it's USB socket had a loose connection as well, it was only a couple of months old. I dread to think what level of stability/quality power it was actually putting out. The eGo charger that I bought, also a couple of months old, has also broke as well, red light stays on and never goes green. I've ordered an official Kanger charger in the hope it should be of better quality. I was struggling to find a decent AC adapter that had a 0.5A output, but I've managed to now.