Can storing a hard drive near an electric wire (220V) damage the hard drive?

I have no clue about such things so I thought I'd ask here. It's just that I found a suitable storage place for one of my external drives, but there's electric wire nearby.

migrated from stackoverflow.com May 24 '11 at 20:51

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    If you wrap a single-conductor wire around your drive tightly a few hundred times and pass current through it, you'll find all your data gone ;-) – Mike Pennington May 24 '11 at 20:50
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    @Mike: Not really - the hard drive casing is typically made of a ferromagnetic metal and acts as a shield against external magnetic fields. Moreover, it takes a VERY strong field to affect the platter - there's already an extremely strong neodymium magnetic in most HDDs for the voice coil after all. The HDD makes this field for write operations by placing the write head very close to the platter, but this won't be the case for your external electromagnet. – bdonlan May 24 '11 at 20:56
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    Yes, on the order of several Tesla. Not the kind of thing you can get by running a few amps through a hundred-turn coil :) – bdonlan May 24 '11 at 21:02
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    @non-humorous people... 1. comment was meant as a joke. 2. I never specified how much current – Mike Pennington May 24 '11 at 21:04
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    I would be more concerned with the dryer lint. ;-) – Chris Nava May 24 '11 at 21:31

Generally speaking, the EMF produced by electrical cabling will not be sufficient to damage or cause data corruption on a hard drive. Electrical cabling can cause interference with network cables, if they run parallel for a long distance; over a long distance the interference adds up, and signals on a network cable are quite weak and thus relatively easily corrupted.

However, in a hard drive, there are several factors acting to reduce the impact of power cable EMF:

  • Traces on a hard drive are very short, and thus don't pick up much energy from the power cables.
  • The hard drive's platter and magnetic read heads are encased in shielding typically made of iron or some other ferromagnetic metal; this shields it from external magnetic fields.
  • Although a SATA or USB cable is similar in some ways to a network cable, the relatively short run length reduces the chance that power cable interference will be significant, and error-correction codes will repair any corruption that does occur.

In short, don't worry about it, unless you're working with some kind of industrial equipment with VERY high currents on that cable (the amount of interference emitted from a power cable is proportional to the current on it). Household currents are unlikely to be a problem.


You do realize computers and their components are powered by electrical wires, and by definition are usually around them, right?

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    Hehe yeah. After asking the question I realized that, and thought that I had probably made a fool of myself. But anyway, I got some interesting information from the great replies from you guys! – Enchilada May 25 '11 at 19:01

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