MobileRead Forums - View Single Post - PRS-650 battery drain

LifeJam · 06-21-2011, 10:51 PM

I've recently experienced the battery drain on PRS-650 and have a reason to believe that the incorrect USB dismount causes the drain.

Most likely what happens is that when the reader is plugged in the PC, the USB drive volumes are mounted automatically (reader, config, and memory card if present).

When the reader gets unplugged without dismounting the drives (in the system tray - 'safely remove hardware and eject media'), the filesystem under certain conditions gets corrupted, and (my guess - most likely) some filesystem related process (either the indexing or filesystem repair) would keep running and drain the battery. Soft reset and recharge by itself don't seem to fix the issue.

This does not happen every time.

Being in a hurry, I've unplugged the USB cable without dismount, and the reader drained on the plane after about an hour of reading. Later I've done a soft reset and charging from both pc and charger, and it kept draining at the rate of about 1 bar per 12 hours in sleep mode without reading.

After reading posts in this thread I've done soft reset again, then plugged in the pc and charged, but this time I was careful to dismount all volumes from the sys tray. Battery drain stopped. Been using the reader in normal regime for 3 days now (about 1.5 hours reading / day, then sleep mode), and still on 4 bars.

Hard reset should be able to fix this issue too (haven't tried myself - no need) as it will probably reformat and restore partition and filesystem to the vanilla state.

06-21-2011, 10:51 PM	#9
LifeJam Junior Member Posts: 2 Karma: 10 Join Date: Jun 2011 Device: PRS-650	battery drain - possible reason - incorrect USB dismount I've recently experienced the battery drain on PRS-650 and have a reason to believe that the incorrect USB dismount causes the drain. Most likely what happens is that when the reader is plugged in the PC, the USB drive volumes are mounted automatically (reader, config, and memory card if present). When the reader gets unplugged without dismounting the drives (in the system tray - 'safely remove hardware and eject media'), the filesystem under certain conditions gets corrupted, and (my guess - most likely) some filesystem related process (either the indexing or filesystem repair) would keep running and drain the battery. Soft reset and recharge by itself don't seem to fix the issue. This does not happen every time. Being in a hurry, I've unplugged the USB cable without dismount, and the reader drained on the plane after about an hour of reading. Later I've done a soft reset and charging from both pc and charger, and it kept draining at the rate of about 1 bar per 12 hours in sleep mode without reading. After reading posts in this thread I've done soft reset again, then plugged in the pc and charged, but this time I was careful to dismount all volumes from the sys tray. Battery drain stopped. Been using the reader in normal regime for 3 days now (about 1.5 hours reading / day, then sleep mode), and still on 4 bars. Hard reset should be able to fix this issue too (haven't tried myself - no need) as it will probably reformat and restore partition and filesystem to the vanilla state.