Developer Forum

I'm about to replace my old UPS with a new one, about 500 VA.

Which manufacturers/models have folks found to be noisy insofar as
X10 signals are concerned? Which have been found to be clean?

Regards,
Charles Sullivan

AFAIK, they are all noisy but mine's plugged into a 5amp ACTAF100 noise
filter and that solves the problem.

John W

In article < XXXX@XXXXX.COM >,


I recently purchased two UPS units, so can give you two points of
reference. FWIW, I don't think either of the units is "noisy", in
the sense that they inject any noise onto the power line, but one
tends to eat X-10 signals (and probably all higher frequency
signals), whereas the other doesn't.

The APC 725 ES did not seem to affect the X-10 signals at all by
itself. In fact, it seems to provide some isolation if an X-10
signal sucker, like my PC, is plugged into it. With just the UPS,
or just an X10 line filter, X10 modules on the same line as the PC
were marginal. With both in line, the X10 modules work reliably.

The Belkin F6C500UNV is quite good at absorbing X-10, so good
in fact that I would not advise using it on circuits with X10
modules present.

(My old AT&T UPSes from the early 1990's, now on their second set
of batteries but still going strong, are all very X-10 friendly.)

My 2 cents, FWIW.

Rob

To quote a keeper of a UPS faq:
Consumer level UPSs compete on cheapness and use
cheap components. You get square waves, not true sine.

My issue was with a 3U 1400VA UPS that was dying.
His reponse was roughly: Anything below 5000VA is consumer.

What to do?

Isolators or filters.

The APC Smart-UPS line has sine wave output. They also put a
heavy load on an X10 signal. I solved that by putting a heavy
duty X10 filter in the circuit that feeds the UPS. The result is
that X10 signals do not get through the UPS but the UPS does
not present an X10 load to the rest of the house.