A Question About Portable Hdds And Battery Life

[seurrep]

I'm not that knowledgeable when it comes to hardware, so apologies if this is a stupid question. I assume that the power consumption between different types of USB powered portable hard drive doesn't vary that much.

If this assumption is true then do you have any idea how much the time the Pandora will last on a single charge will drop by when it is connected to such an HDD the whole time?

 

[roelandb]

If you hook up a device like a portable hard drive, it will consume a lot of energy, and will effectively about halve the battery life (with external drive connected i guess you will get approximately 5 hours of battery.

 

[WizardStan]

The Pandora alone, going full throttle, consumes about 500 milliamps and should last around 8 hours. The USB port is capable of giving 500 milliamps which is the maximum allowed by the standard. Assuming the USB powered hard drive only uses 500 milliamps at most, then it will cut your battery life in half.
However, there is not a consistent power usage among USB powered hard drives. Some hard drives just squeak in below that 500. Others use much more than 500 and have a Y adapter so you can plug them into a second USB port to get more power. The Pandora doesn't have a second port that can be used for that, so you need to ensure that it stays below 500.
Keep in mind as well that even though the standard says 500 is the max, PCs don't necessarily have to limit themselves to this, so it's possible that a USB powered hard drive could draw 600 or 700 milliamps and your PC is happily providing it (outside of spec). The Pandora doesn't have that kind of play, it can't afford to work too far outside of spec, so might fail.
Check the box, check the manual, check online resources, find out exactly how much power your USB drive consumes. If it's less than 500, you're good, other than it will consume about half your battery. But still, 4 hours is pretty good, and it's not like you'd use it all the time, right? Just unplug it when you don't need it.

 

[WoD]

Look into portable chargers like the Proporta Power Pack and better. If you want to use a portable hard drive you're probably going to need to use a portable charger/battery and a USB hub to keep it powered on the go. The Pandora just isn't going to cut it!

http://www.bestofferbuy.com/8in1-10000mAh-Portable-Power-Battery-Pack-DSiDS-LiteNDSPSPCell-PhonesMP3MP4-p-26922.html?currency=GBP&utm_source=gbase&utm_medium=cse&utm_campaign=gbase

Something like this, but less cheap and tacky!

 

[lulzfish]

Also, I think the Pandora is using 3.7 volts from the battery pack, which means the total power draw at 500 mA is much less than a 5 volt USB HDD at 500 mA.

So the battery life might be much less than 50% once you add a hard disk. Probably what you would want is to have it connected as little as possible. If you want to watch a movie, you might even consider copying it to an SD card first, so you have a huge transfer and then the playback is done from an SD card that doesn't need power to stay on like a HDD does.