Re: Central Vac overload

["Robert Green" <robert_green1963@xxxxxxxxx>]

"Existential Angst" <UNfitcat@xxxxxxxxxxxxxxx> wrote in message

<stuff snipped>

> > I am going to try a test today with my Kill-0-Watt meter to see if
there's
> > a
> > substantial increase in current draw.  I might be able to use a current
> > sensor to detect the upswing and sound a chime or some other kind of
> > warning.  I don't want to shorten the life of the motor by letting the
> > thermal overload shut it down after it has overheated.
> >
> > Thanks in advance
>
> I think what you'll find is that your killawatt will show a substantial
> DECREASE in current.  The motor is not laboring, but actually speeding up,
> as there is no air to load it.  Almost counter-intuitive, that as a vacuum
> clogs, it works less!

This is one of those things that I am going to have to check out for myself
because it is so counter-intuitive because the motor whine gets so loud when
it's blocked.  But now that you mentioning, a laboring motor *shouldn't*
speed up at all, so that fact alone means you're mostly likely correct that
I'll see a drop in amperage.

> What is likely happening is that the motor is going out on temperature
> overload, not from current, but from lack of airflow, that cools the
motor.

There are a number of possible issues, from problems with the automation
system that controls the vacuum, to the motor heat overload to an issue with
the "smart outlets."  My original concern was based on what I thought was a
thermal overload kickout, but when I sealed up the unit I left plenty of
room for airflow and even put in a small fan to make sure nothing
overheated.  I realize now I ran those tests during an average vacuuming
session that didn't include the occasional serious clog, so I will have to
see what happens when I deliberately block the hose and monitoring the motor
temperature.

Most of this has been rendered moot by Art T's location of a ready-to-go
valve system designed to detect such problems and remedy them.

http://www.thinkvacuums.com/beam/valve.html

Thanks again, Art.  (And thanks to you, EA, too.)

--
Bobby G.