"w_tom" wrote in message
...
A 3 or 5% reduction in voltage, also known as a brownout to
the utility, is totally irrelevant to electronics and
especially irrelevant to computers. A computer works just
fine even when incandescent bulbs dim to less than 40%
intensity. Even demanded in Intel specifications. IOW what
the utility calls a voltage reduction is full power to the
computer. Utility would have to decrease voltage more than
20% for a computer to see a brownout. But if utility voltage
drops that low, then electric motors may be damaged. IOW
voltage too low to damage electric motors is even full power
to a computer - which demonstrates how resilient a computer
really is.

BTW, utility does not institute a voltage reduction to save
money. Voltage reductions are a last ditch effort to avoid
rolling blackouts.

True - my opinion as well - perhaps you could convince my local utility re
this procedure being used on a daily basis.

Spikes and harmonics are (or should be) irrelevant to a
computer. Again, because the computer is so resilient.
However that internal computer protection assumes the building
has a 'whole house' protector so that spikes cannot overwhelm
computer internal protection.

All of which is irrelevant to HD protection. Either the
power supply will output correct power or it will shutdown.
This, of course, assumes the computer assembler had basic
electrical knowledge and did not install those 'defective by
design' $25 or $40 power supplies. But again, this was
explained earlier.

There is nothing cost effective adjacent to the computer. No
UPS nor power strip protector that will protect computer
hardware. Computer internal protection assumes the building
has implemented a 'whole house' protector on AC mains
connected less than 10 feet to central earth ground.
Protection as it was even done and well proven before WWII.

Perhaps you could explain the half dozen UPS I have seen that operated
correctly and interrupted close in electrical faults.
Naturally the UPS were scrap after the electrical event - but the protected
electronics were ok.
$40 UPS vs $800 desktop or in one situation $200 - $300 UPS vs. $5000 of
servers.

someone wrote:
A brownout is generally recognized as planned voltage cuts -
or undervoltage. My utility in the US routinely implements
3% and 5% voltage cuts to shave or reduce peaks (and
thereby save $' when buying power).

There is also the issue of spikes and harmonics.

Given a current laptop/desktop will be ~ $800USD to ~$4000
for a high performance system and a UPS sells for $40 - why
subject a computer to unexpected power events? What is the
value of the data on the hdd(s)?