Question about 705 connected to USB when computer not on

[LeFlic]

I set off for work this morning and as soon as I turned on the Garmin 705 I got a 'low battery' warning. It lasted for about 40 mins and then died on me.

I had left the 705  connected by USB cable to the computer but the computer was turned off. Has the battery drained because of this?

The only other reason I can think of is that recharging solely via the USB port on a computer doesn't provide enough charge to fill the battery (I tend to download my last ride, then leave it plugged in whilst doing other things on the computer).

As soon as I got into the office I plugged it into the mains charger and it is now fully charged so it certainly seems to be something to do with the computer connection.

LeFlic

[Nonsteeler]

I think you are right. According to wikipedia (http://en.wikipedia.org/wiki/USB#Power_supply) the max power output of a USB port is 0.5A at 5.25V, min seems to be 0.1 A at 4.75V (all with USB 2). My charger of the garmin edge 705 claims to have an power output of 1A at 5V, which is roughly double amount of power compared to USB output. So yes, it should take considerably longer to charge the 705 via usb-ports.

This is also the reason why such a charger can destroy equipment which is not made for such strong electrical currents (eg stuff that can only handle the native USB power output).

[tonycollinet]

This is also the reason why such a charger can destroy equipment which is not made for such strong electrical currents (eg stuff that can only handle the native USB power output).

That is not quite correct. As long as your charger accurately regulates the voltage to 5V, then no equipment that is properly designed for a 5V input will be damaged - regardless of the current output *capability* of your charger.

IE your charger only delivers the current demanded by the connected device at 5V

[Nonsteeler]

This is also the reason why such a charger can destroy equipment which is not made for such strong electrical currents (eg stuff that can only handle the native USB power output).

That is not quite correct. As long as your charger accurately regulates the voltage to 5V, then no equipment that is properly designed for a 5V input will be damaged - regardless of the current output *capability* of your charger.

That is quite interesting. In 2007, a friend of mine used the charger of my iAudio Player to charge his basic GPS thinny (can't remember the model). The GPS died after this treatment. The iAudio charger had the same power out as the Garmin 705 charger. My friend called the company, described the problem. They acknowledged the problem by saying it is stupid that that there is no standard for chargers. Nevertheless it fell under their warranty and my friend got a new GPS device, although, if you're right it was the sole fault of the (wrong/badly made) charger (used by ignorant people) and had nothing to do with the GPS device itself.

[Cunobelin]

I had left the 705  connected by USB cable to the computer but the computer was turned off. Has the battery drained because of this?

LeFlic

Many computers cease providing power to the USB ports when the computer is turned off.

It could be that simple!

The Edge didn't charge because when you switched the machine off the main boards which feeed the USB are closed down and no power reaches the port.

Plug in the Edge and watch the "Charging in pogress" display, now close down and see what happens. If my premise is right the message will disappear as the supply is terminated.