installing a light switch
- Thread starter Yoga Face
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If it really is the easiest job in the world, why do you imagine the OP was so perplexed he came here and asked for advice? Step 1: Ask a coherent, accurately detailed question of those unknown, anonymous ignoramuses (and others many well-informed, but how would the OP know or judge?) you seek advice from. Or get a book. Or call an electrician.
If electricity wasn't dangerous for the ignorant we wouldn't have ESA inspectors, or UL and CSA labels.
When the guy hasn't even formulated a proper question, enabling him by advice based on guesses about what he's facing is a very bad idea. You're an engineer, when someone asks the safe load for one of those steel alphabet-joist-thingies, do you ask TERB, or go to your manuals, and demand more info about the use-situation the questioner is concerned about?
DIY is great, I personally recommend the Ontario Electrical Code Simplified; vol. 1 available for purchase at Home Depot or free at any Library. It got my DIY wiring inspected and approved. But guesswork coming and going is exactly what gives DIY a bad name.
that is the way it is configured and it works
the live wire coming in is black and it is connected to another black wire that seems to go directly to the stove light , not the stove proper, and the stove light is turned on by the stove light switch
these two wires have a third black wire connected to them that becomes connected to the light switch
the other wire is white and must go directly to the kitchen light
I believe this is called series connection because when I turn the stove light on the kitchen light does not diminish
this means my electricity bill rises when both are on
if it was parallel the lights would dim when they are both on and there would be no rise in my bill
there is no ground wire as the box is metal and acts as the ground so the box is hot so you need to turn off power in case you touch your screwdriver to the box
this is how I perceive the situation
new switch is installed and working fine
You are right, I apologize. I misread your original post.
I tried to be careful in my wording: "the wires are 180 degrees out of phase (kind-of like polarity, but not the same thing)"
The transformer on the street that feeds your house is a 240V center tapped transformer. The center tap is grounded at the transformer and 3 wires come into your house, 1 x neutral and 2 x 120V live wires. The neutral is grounded again at the panel and the two lives go to the two breaker busses.
Easy part to understand: If you were to put an AC voltmeter across the ground and either of live-1 or live-2 wires you would read 120V AC RMS. If you put the voltmeter across live-1 and live-2 you would read 240V AC.
Hard part to explain: We all know AC doesn't have polarity in the same sense as the DC world (i.e. + and -), but in reality it sort-of does. AC voltage a 60 Hz sine wave that has a +120V RMS swing for 1/120th of a second and a -120V swing for 1/120th of a second around a center point. In residential wiring that center point is grounded and therefore at 0V. Even though the waveform swings between +120V and -120 V WITH RESPECT TO GROUND, the AC voltmeter simply reads that as 120V. Even if you switch the two voltmeter leads around it still reads 120V (i.e AC meter doesn't read + and -, even though the waveform is going +/- every 18.3ms - that's because it's displaying as RMS voltage)
For household wiring; when live-1 is at it's +120V swing, live-2 is at it's -120V swing WITH RESPECT TO GROUND <-- this is the key to my whole post. The AC voltmeter reads that as 240V. Here's a good diagram I found on the net: http://www.globalspec.com/ImageRepo...ansparente0e210f2a73b4e2aa95274447e1b5892.gif
Therefore the live-1 and live-2 are 180 degrees out of phase with each other IN RESPECT TO GROUND, although it's technically still considered single phase wiring. That's why I added "kind-of like polarity, but not the same thing". Unless you see the sine waves on a oscilloscope or diagram and understand that voltage is "potential difference" it's hard to picture in your head.
^^^ correct.
Your link to the diagram of the transformer is correct.
A lot of people mistakenly think that residential 120/240 has 2 phases. It does not. The center tap on the transformer is the neutral. In essence, the neutral only carries the unbalanced load between the 2 lines (when it exists). Hence why the most recent electrical code now allows a smaller neutral wire than either line. (For example, for a 100 amp service, the line conductor required is No. 3 RW90 conductor for either line, however, the new electrical code allows No. 6 RW90 for the neutral. The old electrical code required No. 3 for the neutral, the same as the lines.)
Your link to the diagram of the transformer is correct.
A lot of people mistakenly think that residential 120/240 has 2 phases. It does not. The center tap on the transformer is the neutral. In essence, the neutral only carries the unbalanced load between the 2 lines (when it exists). Hence why the most recent electrical code now allows a smaller neutral wire than either line. (For example, for a 100 amp service, the line conductor required is No. 3 RW90 conductor for either line, however, the new electrical code allows No. 6 RW90 for the neutral. The old electrical code required No. 3 for the neutral, the same as the lines.)
It's kind-of hard to follow your wording, but I believe you have the series connection and parallel connection exactly backwards. Here's a simple picture: http://socratic.org/questions/what-type-of-circuit-is-economically-better-series-or-parallel.
If 2 lights were wired in series, which they never are for normal household lighting, each would only burn at 1/2 brightness, but your electrical bill would be the same as only one one light.
In parallel, both would be full brightness and would draw a total of 2X the power, thus doubling your cost.
Again, hard to follow your wording, but every electrical box in your house is grounded via the non-insulated ground wire that should be around a screw in the back of the box, assuming the work was done right. That said, really old homes might not have ground wires, I've definitely seen this in older parts of the city. If there is no ground wire, then the box is NOT grounded and it "floats" electrically, but unless something is wrong, it won't be energised.
Good for you! It really is easy to do. A little more care is required for 3 way switches as well as plugs, but both are still DIY.
Agreed. That's why electricians try to balance each side of the 120v live wires when they install a panel so they each run roughly the same amperage. This can never be achieved 100% of the time, but the goal is to get current on the neutral wire as close to 0 amps as possible. There's a term for this that I forget, but it basically results in lost power revenue in the old analog power meters. In addition power factor correction is becoming an issue in homes (due to pool pumps and ballasts in fluorescent lights) and my electrician buddy says he's installing power factor correction devices in some home jobs.
Another thing people don't realize: although the neutral is grounded at the panel, it's not necessarily at 0V with respect to ground. It is possible to get a shock from the neutral wire.
I note that after all the help from TERBians, and your self-proclaimed success, you still haven't been able to describe your wiring accurately. Any simple off-on switch functions by interrupting and restoring the current in a wire. The current-carrying wire is cut, and the two ends are attached to the two terminals of the switch. However the circuit is configured there are two wire-ends connected to every switch. You have described just one connection.
How your switch operates with just a single terminal connected is a special-case demonstration of that Providence I mentioned earlier. Give thanks.
The switch is simply that, it switches the 120 volt source on the load side of the switch on or off. The other side of the switch is the line side and is live all the time.
Yoga Face didn't claim he had any expertise and turned to the community for help. Why are you being so difficult? Your wording doesn't even make any sense!
What more would you like to know? This is a simple 2-way switch swap. Unless he tried tracing the wires (which isn't straight-forward), the only important things to verify are i) it's indeed a 2-way switch and ii) it wasn't aluminum wiring.
One item I forgot to say originally: technically it's illegal to put 2 wires under one screw, although allot of professionals do it. One wire should go under the screw and the second wire can go into the push-in wire connector (make sure to use the right one!). Alternatively, you can marret (spelling?) the two wires together with a third wire that then goes to the switch.
Trouble is he didn't — and hasn't yet — identify it as a 2-way switch. Everyone just assumed it was. He hasn't even said whether his "…stove light" is a house-fixture over the stove controlled by a wall switch, a light that's part of the stove, or some third possibility like a lamp in an exhaust hood. Nor has he yet supplied any accurate description of the box it is presumably mounted in and the wires there. As buttercup was first to say, and as I repeated with emphasis, that vague and partial description should have alerted anyone knowledgeable that they'd be assisting a potentially dangerous operation without all the facts.
No one is asking him to trace the wires, but a proper description shouldn't be too much to ask of anyone who is asking for help. I'd be happy to clarify whatever part of my own post replying to YogaFace confused you.
Had the OP simply said, " I have a lightswitch that's no longer working. Can I replace it with a similar one, by just moving the wires from the defective one to the same terminals on the new switch, with the power off at the panel? Or is there more to it?". The answer would have been simply, "Yup, just make sure all the new connections are tight and secure", and not taken the two pages of 'clarifications' and irrelevant tech-talk that it has so far.
In the end, all that needed to be said was, "Shut off the power supply to the switch, attach the new switch of the same type as the old one, to the same wires in the same way as the old one. Restore power and test." Which was what YogaFace apparently did, all by himself.
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it is a 2 way switch
the stove light is a house light that sits over the stove along with an exhaust hood and fan
I cannot reconnect the wires like they were connected to the old switch because I never took the old switch out
so, we have a two way switch and two wires, both black
the live wire branches off to the stove light
the dead wire connects to the ceiling light
two wires and two connections on the two way switch
does it matter which wire goes where ?
the answer appears to be no
I vote for an electrician or a double indemnity clause on your insurance before you start the project.
As a home handyman that only does basic wiring, I am a little confused by your description.
Is it a two way switch or double switch ?
A two way would turn on either the ceiling light or the stove light. Is that what you want ?
I vote for an electrician or a double indemnity clause on your insurance before you start the project.
As a home handyman that only does basic wiring, I am a little confused by your description.
Is it a two way switch or double switch ?
A two way would turn on either the ceiling light or the stove light. Is that what you want ?
it is one switch and two wires connect to it
it is two way only in the sense it can be switched into two positions ie on and off
so I assume it is not a two way switch as it has one switch on it
I vote for an electrician or a double indemnity clause on your insurance before you start the project.
As a home handyman that only does basic wiring, I am a little confused by your description.
Is it a two way switch or double switch ?
A two way would turn on either the ceiling light or the stove light. Is that what you want ?
D'OH! That's a picture of a dual 3-way switch. You can tell because it has 6 screws.
No, no. LOL. Does the switch have 2 screws or 3? If it has two 2 it's a 2-way switch. If it has 3 it's a 3 way switch. <-- both of these switches only have 2 physical positions - up or down (there's probably a better term, but I can't think of one).
There are single switches which have 4 screws, these are used as a 3rd switch in a 2-way switch circuit ..... but I don't want to complicate things further.
Yes - I just looked at the toggles without counting the screws - it's not that common. I'm curious about the application.
We all have our unique ways of describing a switch but in my ancient days - two way switch suggests that there are two positions that the switch can make contact (e.i: single pole / double throw). A typical two way switch in house wiring is used like this:
These would be used to control a light from two different locations (ex: a hall light from top and bottom of a staircase)
huckfinn
My book has been banned from schools.
Does the stove light operate when the switch is not installed?
Also, is the black wire coming from the stove light live?
Also, is the black wire coming from the stove light live?
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