I recently began a project where I built a shelf and moved lots of my
computer stuff under the floor and into my basement. Part of it was a mount
a power strip with a 15' extension cord onto the ceiling and then use those
U shaped nails to neatly get the cord to the electrical socket. I spent a
whole day doing it and when I was done, everything was great - except that
when I turned off the basement light, the battery backup started beeping.
The electric socket is switched...
There are two flat cables leading into the socket (which is mounted on the
ceiling) and one that comes out. This one goes to a light. That light does
NOT go on or off with the switch. It's my intention to open the box and
rewire it to not be switched. Before I cut the power, can anyone give me an
idea of what I'll see when I open it, and what the best way will be to make
it not turn off when the switch is thrown.
Maybe one line just happens to pass under the switch, and all I'll have to
do is switch between the outlet and the light (I wouldn't mind if the light
All you have to do is connect your wires to the same wires as the unswitched
light, and you'll have an unswitched outlet. If you want the light to be
switched, connect the wires going to the light, to the wires your outlet is
currently connected to
Just go to the cutlery drawer, get a regular dinner knife and jam it into
the socket in question while a friend flicks the switch on and off...
Seriously - it may not be an easy fix. You don't sound too much like you
know what you're doing.
If you just *have* to do it yourself - your local library has tons of books
on electrical repairs and would be a perfect place to start. I recommend
Well I was a EE in college, but I know alot more about stuff that runs at 5V
than 120. I'm not worried that I won't be able to figure it out, I'm just
looking for a heads up because I can forsee being in the basement with a
flashlight trying to figure the whole tihng out while everyone is whining
about the power being out...
I was studying digital electronics in college, but did once take an
elective course in NEC. I remember getting one test question "wrong",
in one of those cases where you get penalized for knowing something
you aren't expected to.
The question was about a 3-phase wye-connected motor, and asked True
or False: the current in each leg is the same. The supposed "correct"
answer was True, although I knew that was impossible. One of things
they taught in electronics was that the sum of the currents in a node
is always zero (electrons are flowing FROM somewhere TO somewhere).
The currents could never be equal unless they were all zero.
Sounds like a classic case of both answers being right!
Measured instantaneously, you're correct - the sum of the 3 legs will be zero,
but different currents (or 0) will be flowing
in each leg.
But on an average basis, like if you connected an ammeter, you'd read the same
current on all 3.
It doesn't have to be instantaneous for the currents to be unequal.
There is a difference in phase. My "problem" was in failing to know
that one of the important characteristics (phase) was supposed to be
BTW, in a different class I had just been taught about phase, and the
way the phase of the voltage and the phase of the current can be
affected by components in the circuit (power factor). Obviously, 120V
@ 0 degrees is NOT the same thing as 120V @ 120 degrees.
Since ammeters don't show phase. Phase is still real, as you should
They were asking about time-averaged current of some sort, probably RMS
current, while you were thinking in terms of instantaneous current.
That's sort of like being asked a question on a high school physics test
about the validity of Newton's laws when you already know about
relativity. *You* know that Newton's laws are not always valid, but at
the same time you should be able to figure out that *in the context of
the physics class*, they are.
By "instantaneous current", I really meant "instantaneous current as a
function of time". If you look at the phase currents with an
oscilloscope, you can see that there is a phase shift between phases,
so the current waveforms are not equal. The question was asking about
average current as a scalar, not vector, quantity.
Or more generally, providing the "full" answer to a question when the
asker only wanted the quick one-sentence executive summary. Most people
just want an answer, they don't want to understand the reason behind the
answer. I'm one of the people who always wants to know where the answer
came from, and how approximate the answer is, but I seem to be in a
You can buy a thing that fits over the screws on a standard switch
cover that prevents anyone from turning the switch OFF (or ON if it's
reversed). You dont need to even touch the wiring. just remove the
screws from the switch plate, stick the thing on the plate and put the
screws back. I saw them at Ace Hardware (I think thats where). The
cost is under $5
By the way, did you try BOTH of the halves of the DUPLEX outlet?
Often half is switched, the other half is not.
Yeah, but then I wouldn't be able to turn off the lights ;-) Right now I've
got duct tape performing the same task so the kids don't zap my internet
Yes, I did try both... I was sure that one was going to stay on, like you
suggested, but that wasn't the case.
I agree, but if he dont know electricity he has to call an electrician
and we all know what that costs. He could just put a pull chain on
the light too, or another way would be to buy a long extension cord
that is a #12 or at least a #14 and use another outlet further away.
That's not necessarily the ideal situation, but computers dont use
that much power, and the wire gauge is the same as whats in the wall
It's sort of odd that BOTH halves are switched. Usually it's just
If this was my problem, I'd just put another dedicated outlet there
and leave the old one alone.
Perhaps the better choice would be to create a brand new circuit just for
the computer equipment. Add a circuit breaker, string some wire and
Sometimes computers like to be isolated from everything else. There would
then be no dimming of lights when the printer kicks in. Less chance of
breaker blown because of something else on the line.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.