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David Farber David Farber is offline
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Default Power supply for USB to SATA adapter smoked on first use.

Ralph Mowery wrote:
"whit3rd" wrote in message
...
...have received the replacement which I haven't plugged in yet.
(When I do, it's going to be in a series with 60 watt light bulb!)


The light bulb in series is a bad plan; the power supply will, in
order to deliver
regulated output power, draw higher current due to the lower input
voltage,
and fry the fuse, even if it isn't faulty.

Most common problem that makes the fuses fry: shorted diode in the AC
rectifier (usually full bridge).


The light bulb will limit the current to around what the bulb is
rated for. That is a 100 watt bulb will limit at about 1 amp and a 60
watt bulb to about 1/2 amp. At low current the bulb is like a very
low resistance and as more current is drawn and the bulb lights up it
acts like a higher resistance.


I was thinking of connecting the bulb without a load just to make sure there
were no direct shorts before I plugged it in the very first time, not to use
it like that in a real-world situation.

Thanks for your reply.
--
David Farber
Los Osos, CA