AUGUST 2021 MACWORLD 109It lacks an alert
for wiring faults, a
nice extra on most
UPSes that can
alert you to
dangerous home-
wiring issues.
This Amazon
model produces a
simulated
“stepped” or
chunky sine wave
for alternating-
current (AC) power
output, as noted
earlier, instead of
the smooth sine
wave that comes out of a wall socket—
which slightly more expensive UPS
models can produce. A simulated sine
wave can interact poorly with computers
that use modern power supplies with
active power factor correction (PFC).
These supplies use power more efficiently
and can automatically adjust voltage
without manual switches or modifications
across the power systems used in
different countries.
For voltage correction and short
periods of time, a stepped sine wave is not
likely to cause substantial problems, but
the power supply might produce a high-
pitched whine. If you have expensive
hardware or experience frequent powerThe outlet pattern is a little close
together if you have several devices that
rely on the wall-wart style of DC adapter.
The UPS has one outlet in each group of
four that’s 2.25 inches away from the next
group of three, which are spaced 1.25
inches apart. Outlets are spaced correctly
for standard 2-prong and 3-prong cords
used in electronics.
Simplicity is the watchword on this
model, which has a single button on the
top that powers the unit on and off, and
also manages some alarm-sound settings.
Its LED lights up green in normal use and
flashes (along with emitting beeps) when
it’s in battery mode and when its battery is
about to be depleted.
An onboard alarm can sound to warn you when the devices you’ve
plugged in the AmazonBasics UPS are receiving power from its battery.