[GTALUG] mysterious restarts

[Bob Jonkman]

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Alvin Starr wrote:
> A lot of UPSs switch from the mains to battery once the power drops
> and that delay can be enough to cause some power supplies to lose
> enough power to fail

If that happens then your UPS is broken. The whole point of a UPS is
to supply *uninterruptable* power. Even the simplest pass-through
UPSes I know about can switch from line to battery in the space of a
single waveform (ie. within 1/60th of a second). Not much point in
having a UPS if it makes all your equipment reboot when the power goes
out.

- --Bob.


- --
Bob Jonkman <bjonkman at sobac.com>          Phone: +1-519-635-9413
SOBAC Microcomputer Services             http://sobac.com/sobac/
Software   ---   Office & Business Automation   ---   Consulting
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On 2016-06-14 11:30 AM, Alvin Starr via talk wrote:
> On 06/14/2016 11:23 AM, Russell Reiter via talk wrote:
>> On 6/14/16, D. Hugh Redelmeier via talk <talk at gtalug.org> wrote:
>>> We have a computer that started doing random and frequent 
>>> restarts on the weekend.  We don't know why.
>>> 
>>> Any suggestions?
>> You don't mention whether or not the system is protected by UPS.
>> 
>> I live in an area with somewhat spotty electrical service, an 
>> older building near the exhibition grounds. When they liven up 
>> the CNE grounds in the spring, I experience brown-outs quite 
>> often.
>> 
>> Most recently the city has replaced the streetcar overhead wires
>>  and de-energized and re-energized the system, both times I had 
>> spontaneous reboots. One of the TTC engineers told me the new 
>> streetcars require more voltage and they are replacing the wires
>>  with heavier gauge ones throughout the city.
>> 
>> Are you near streetcar tracks where they may be replacing wiring
>>  or perhaps near one of the transformers which convert AC to DC?
>> 
>> 
>> 
> As a note I have been burned by lower cost UPSs and heavily loaded 
> servers with no hold time in the power supplies.
> 
> A lot of UPSs switch from the mains to battery once the power drops
> and that delay can be enough to cause some power supplies to lose
> enough power to fail.
> 
> 
> 
> 
> --- Talk Mailing List talk at gtalug.org 
> https://gtalug.org/mailman/listinfo/talk
> 
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