sm1thson

hi, the question is:
will a crank break my harddrive?

the details are, my system will be laptop powered so cranking not a problem! -but i will have an external harddrive for the MP3's that will require a seperate power supply (12V & 5V) im planning on using a low dropout reg for the 12V and a 7805 for the 5V (i know the nicer way would be to boost the 5V back up to 12V but i cant be bothered (but i might!)), if its running when i crank what will happen to th Hard drive will it just stutter or crash or die?

p.s. how much current does a harddrive (desktop) need, on both the 5V line and the 12V line?

how low can the voltage go on the 12V line before it complains?

i might build a tank circuit -small lead acid batteries are on sale at maplin at the mo! depends on your answears i guess!

david_594

this is not exactly what you are talking about... but i just got my replacement hardrive from WD after my usb external drive died... here what happened...
i was transfering files to it for the first time(brand new) and the power cable to it accidently got disconnected. When i plugged it back in and windows detected it, it told me to format the drive. So i started the format, and that failed and i got data errors from the drive after that.
so i suggest you be really careful with your drive

TruckinMP3

Hitting a harddrive with the crankshaft is not recommended

Power issues are the worst to diagnose or fix.... Read up and pick your power solution. Better to spend more money on the PS than to have even one problem.

__________________
TruckinMP3
D201GLY2, DC-DC power, 14in LCD ;) 3.5 inch SATA

Self Proclaimed Spoon feeder!

Yes, you should search... and Yes, It has been covered before!

Read the FAQ!

sm1thson

decided its not worth the risk, -tank circuit it is! just picked got a 12V 1.3AH lead acid sealed bat, for £5 its better safe than sorry.

mhorton

Most drives have this printed on the label somewhere. It's different for different drives.

At work I've had experience working on computers using weak 120VAC (40-60 watt) power supplies. They tend to overheat blow a cap and the output goes out of spec. I've seen drives spin down when the voltage is below 11v, and above ~13.5v too. I think it varies a lot from one drive to another. But I definately have seen poor power kill drives permanently. All this is relating to defective power supplies providing a constant out of spec output, so it may not be relative to a momentary voltage dip from a crank.

crashwg

what exactly is a tank circuit? I'm planning on putting in a firewire drive so this might be usefull information...