Another dead power supply

[Alex Beamish]

On 12/3/05, phiscock-g851W1bGYuGnS0EtXVNi6w at public.gmane.org <phiscock-g851W1bGYuGnS0EtXVNi6w at public.gmane.org> wrote:
>
>
> For the second time in as many years, a power supply in one of my
> computers has died.
>
> The previous power supply death took out every item in the box with it.
>
> This time, there was some sort of over-protection device that prevented
> the power supply from damaging anything. Apparently some power supplies
> have a zener diode across the output that clamps the output voltage to
> about 5.1 volts. When the output voltage attempts to rise, the zener
> conducts and gets hot. This is sensed by some sort of temperature sensor,
> which then shuts down the supply.
>
> Both these power supply failures were white box units from OTA on College
> Street. The first one they eventually gave me something of a deal to
> replace the contents of the box, but only after some serious arguing. (The
> OTA manager argued that the failure occurred because I didn't have a surge
> protector on that circuit, which is nonsense. I've designed switching
> power supplies, so I'm aware of the importance of output protection, and
> that supply obviously didn't have it.)


I bought my first PC, a 486/66, from OTA.

Since then I've bought used computers from Canada Direct, also on College
(stereos and computers upstairs, computer books downstairs -- do I have the
name right?) who were great, and an iMac from CPUsed on Dupont, who were
also great.

I bought a new PC (in kit form) from Sonnam that my wife and I put together
for her -- and that power supply blew. I took the unit in (they were a bit
shocked that I'd managed to remove the unit from the PC), but with the right
paper work gave me a new unit without any haggling, which since then
(perhaps two years now) has worked fine.

I haven't bought anything in OTA in years -- not since I bought an
additional 4M memory for my 486/66 so it could run OS/2 decently.

Alex

The moral: buy a good power supply, and make sure it has some sort of
> protection circuit on the output.
>
> Peter
> --
> Peter Hiscocks
> Professor Emeritus,
> Electrical and Computer Engineering,
> Ryerson University
> 416-465-3007
> www.ee.ryerson.ca/~phiscock
>
> --
> The Toronto Linux Users Group.      Meetings: http://tlug.ss.org
> TLUG requests: Linux topics, No HTML, wrap text below 80 columns
> How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml
>



--
----------
Linux, Firefox and GMail .. what a combination.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://gtalug.org/pipermail/legacy/attachments/20051204/183e26d4/attachment.html>