Foo Lim wrote:
> BTW, how do servers with hot-swappable SCSI drives deal with this?  Does
> this mean power supply manufacturers will soon be releasing better and
> more flexible power connectors for regular consumption?  (I wouldn't hold
> my breath.)

It's a combination of connectors that make/release grounding connections
earlier than signal connections, plus specialized chips that control
power application. Eg, when contact is first made, the drive's filter
capacitors will -- for a very short time -- act like dead shorts across
the power bus. The resulting surge of current wreaks havoc on the 
other hardware connected to the sourcing power supply, and tends to 
weld the contacts on the connector. Telephone companies have a huge
interest in hot-swap techniques, since they can't very well just
turn off everyone's phone circuit while they replace a defective
card. If you're interested in more details than this, here are
some chips that one could use to do hot-swap: 

http://www.linear-tech.com/prod/prod_home.html?product_family=hotswap

HTH, 
Chuck
-- 
Power corrupts, but intermittent power corrupts absolutely.

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