Distribution and use of electricity throughout the home. Electrical standards vary greatly worldwide, so providing your location in your question or your profile helps ensure you get answers that are relevant to you.

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4
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1answer
2k views

How do I install electrical through stucco

Is there such a thing as an "old work" stucco junction box? Rather than cutting and flashing a 4" hole for a new junction box, can I cut a 1/2 hole for the non-metallic cable, and attach some sort of ...
13
votes
3answers
1k views

Can I safely use a switch rated for “1A at 125V” with 240V, assuming I stay below 125W?

I recently purchased a foot switch for a standing lamp. The switch is rated for 1A at 125V. I would like to use this switch with a low energy lamp (typically 10W or below) but with a 240V supply. Is ...
12
votes
3answers
1k views

Is there ever a reason for reversing hot and neutral on a receptacle?

I moved into a new home and several receptacles have the hot and neutral reversed. I confirmed this with a basic receptacle tester. I opened one up and found the white wire on the brass terminal, ...
12
votes
3answers
587 views

What is “knob and tube wiring”?

I assume this is some USA wiring system, am I right?
11
votes
3answers
945 views

What size extension cord should I use for multiple computers?

We're hosting a LAN party (several computers, 50+) and I had some questions about power draw; I hope this is the right place to ask. Currently, we're assuming each PC will draw an average of 3.5 ...
11
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3answers
7k views

Are both legs of a home's power supply equally used?

This is basically just to satisfy my curiosity. Please correct me if I'm wrong about any of this: I believe power supply to a home's main panel usually consists of: A neutral wire A hot wire 120 ...
11
votes
7answers
879 views

What's the least intrusive way to find out what's in a wall?

I'm getting ready to mount a flatscreen TV on our living room wall and would like to route various cables through it (e.g. surround sound speakers, HDMI, etc). I appreciate the AWESOME tips here, but ...
10
votes
1answer
564 views

Humming Ceiling Fans

I have two Harbor Breeze 52in. Builders Series Ceiling Fans. Under normal operation these fans are smooth and quiet. However, during power outages like we've had recently, I use a Devilbiss 6000 ...
10
votes
4answers
545 views

How do I use three-prong appliances when my outlets are mostly two-prong?

I am living in a house where most electrical outlets are two prong. There are a smattering of three prong, in particular where an addition was put on. Am I hosed when it comes to where I can plug in ...
9
votes
2answers
4k views

How can I add a circuit breaker when there are no openings available in the neutral bus bar?

I'm trying to add a 20 amp circuit breaker into my existing main panel. The main panel has one vacant slot to put the breaker, but the neutral and ground bars have no more vacant slots. My question is ...
9
votes
5answers
44k views

How do I add more circuit breakers once the breaker box is full?

My house was completely rewired by the previous owner. They tore out all the old knob-and-tube and replaced it with modern wiring. I definitely appreciate this, but unfortunately they left ...
8
votes
1answer
2k views

How can I trace cable through floors and walls?

How can I work out where an electrical cable runs through walls/floors? I am building a circuit map of a 1941 house with unfinished basement. I shut off all circuits at the main service panel, switch ...
8
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2answers
3k views

How can I stop bulbs from buzzing when dimmed?

I've got some hanging lights with "Fat Albert" bulbs that are plugged into a dimmer switch. When they're dimmed to certain levels, the bulbs make a soft buzzing sound. The buzz is amplified and ...
7
votes
2answers
435 views

Why were only some of my tools damaged when connected to a 240V receptacle?

I live in the US and recently bought a home. There are several electrical outlets in my garage. I have recently had two tools that have burned up and gone to an early grave. It turns out that the ...
7
votes
3answers
3k views

Can I use two wire nuts instead of one to connect 6 wires inside a 3-gang box?

Is it considered acceptable practice to use two wirenuts in a situation where it is possible to use only one but may be easier to use two? I have a three-gang box with six cables coming into it. The ...
7
votes
1answer
1k views

Any reason not to ground the sheathing of MX wire?

Having recently bought an older house (c1943) I am doing a little work on the place. While rewiring a light switch I noted that there is newer Romex wiring from the distribution panel to the switch, ...
7
votes
1answer
18k views

Light switch setup using only hot wire. Is it normal?

I was changing the light switches around the house when I came upon this setup. The two switches to the right are all wired using the hot wire (black) from the two electrical wire on the back panel. ...
7
votes
3answers
3k views

How can I improve the wiring under the sink for a garbage disposal?

My vegetable sprayer line broke yesterday, which led me underneath my sink. It wasn't until I was kneeling in a large puddle of water with the line draining on me and the floor that I realized how bad ...
7
votes
2answers
1k views

Are there any “easy” ways to trace a home electrical system?

We bought a home a few months ago, and the electrical panel (and subpanel) are completely unlabelled. We have no way, short of flipping breakers, to know what breaker powers which fixtures. Is there a ...
6
votes
3answers
1k views

Are extension cords safe for permanent use?

I recently learned (via a rant from an electrician's son and some internet research) that the standard buy-anywhere cheapo extension cords are a big cause of electrical fires and are not recommended ...
6
votes
1answer
30k views

Why is my air conditioner tripping the circuit breaker?

Our air conditioner recently stopped blowing out cold air. When I went to check on it, I noticed that the outside unit wasn't coming on. We had had problems with ants in the contacter in the past, ...
6
votes
2answers
431 views

Does lamp maximum wattage matter for CF bulbs? [duplicate]

Say I have a table lamp that states (via a slightly scary sticker) that it takes a 60W max bulb. Of course, that was based around incandescent wattages. Is there any risk with putting in a CF bulb ...
6
votes
2answers
6k views

Why does my fluorescent light fixture take minutes to turn on in high heat and humidity?

Our kitchen fixture won't come on for 3 to 5 minutes when the temperature goes over 90°F (32.2°C) and 90% humidity. It flickers and only reaches 80% brightness after that. It will occasionally ...
6
votes
5answers
11k views

Is there an NEC-compliant method of repairing minor damage to electrical wire insulation without a junction box?

While trying to pry loose a stubborn cable staple that fastens a 14-gauge electrical cable to a stud, I accidentally tore a very small hole through both the outer jacket and the insulation around the ...
6
votes
3answers
2k views

What to do with an apartment with only 2-pronged outlets

I just rented an apartment (Colorado, for what it's worth RE code) that has 2-pronged outlets throughout the place except for two GFCI's, one in the bathroom and one in the kitchen. I bought the ...
5
votes
3answers
6k views

How can I rewire my bathroom fan, light, and receptacle?

My bathroom has one switch that powers the fan and light. In that electrical box, there is also a hard wired electrical outlet that sits in the bathroom. Since I don't have room for a 2 gang box in ...
5
votes
2answers
4k views

How to determine the correct capacity for a sub-panel for a shop?

I plan to install a sub-panel for my woodworking shop, and would like to determine the total capacity that should supply that sub-panel. These are the main items that will likely be running in the ...
5
votes
1answer
2k views

Can I replace an old exhaust fan and connect it to an existing light switch?

I just purchased a new home and in one of the bathrooms there is an old exhaust fan and two light switches. There is a recessed light located in the ceiling above the shower and another light above ...
5
votes
2answers
3k views

What about a light switch in the closet?

Okay you guys I have next question. And like all good questions this one begins with a story. I was reading the post about a nick in a wire and read a couple of you mention that light switch in a ...
5
votes
1answer
708 views

How to deal with abandoned wire?

There is a 240V/30A circuit in a room of my house that used to be a patio. I think it was used for a baseboard/electric heater system. It had a surface mounted outlet that I have removed, but now I ...
5
votes
3answers
742 views

What's the best way to label a double gang box with two circuits

I'm installing some lights in my basement, and will be replacing the single gang box in the hall (currently only for hall light) with a double gang box. The idea is to accommodate the hall light ...
5
votes
7answers
4k views

How can I create circuit diagrams and what program should I use?

Circuit diagrams are very handy. On this site, they can really help illustrate the problem or solution (see here). They can help you visualize what needs to be changed when doing work on your house, ...
4
votes
2answers
264 views

What type of wire should I use to feed a 70 ampere subpanel?

Finishing a basement and I need to add a subpanel. Main panel is outside. Subpanel will be in the basement. 70 Amp breaker in the main to feed the subpanel. I was thinking THHN but would this mean ...
4
votes
2answers
1k views

Can my apartment's electricity harm my computer? Is there an easy way to test the electricity?

I live in a (rented, 1980 built) row townhouse in the USA with slightly suspect electricity: A few of the outlets and light switches in the house (in various rooms) don't work at all. (Even ...
4
votes
1answer
2k views

How can I diagnose disturbing voltage potentials?

Earlier today, I read Acceptable ground to neutral voltage?, and thought it'd be fun to stick my multimeter in the socket and have a voltage to report back. Neutral to ground read 60 volts. My head ...
3
votes
1answer
48 views

What's the recommended procedure for converting a single circuit light switch into two switches for controlling a bathroom fan?

I think my question might be similar to Controlling two fixtures on same circuit independently but I don't need anything as fancy. Summary: I'm remodeling a bathroom. Presently it has one switch ...
3
votes
2answers
2k views

Can I install a Subpanel (in a seperate building) using a 3 wire connection (2 hots and 1 grounded neutral)?

Can I use a 3 wire connection (2 hots and 1 grounded neutral) to install a subpanel in a seperate structure if I install a seperate ground rod to the grounding bus in subpanel? I have 8/3 w/o ground ...
3
votes
4answers
952 views

Will switching to LED lightbulbs make a significant difference in my electric bill?

I asked Reliance Controls about a THP103 meter that I was having trouble with. Turns out that its not a true RMS meter and thus is unable to give you accurate readings on a CFL or LED installation. ...
3
votes
1answer
1k views

When wiring a switch loop, which wire is which?

If you're wiring up a lighting circuit, where the power enters at the lighting outlet. According to the National Electrical Code, which wire should be "hot" and which should be "switched hot"? ...
3
votes
4answers
19k views

How much energy will continuously running a furnace fan use?

We have a bi-level (tri-level? There's a small entry way and utility room, then an upstairs living area and master bedroom and a downstairs living area with bedrooms) in mid-Michigan. The downstairs ...
3
votes
1answer
2k views

Why won't my dimmer dim CFL Lights?

My dinning room had an on/off switch for the light which made it impossible to have romantic dinners there - the light was either too bright or off. So I decided to install a dimmer. Being energy ...
3
votes
2answers
2k views

Is this a valid way to add an electrical outlet?

I've got a feed from my electrical panel in the garage to a single outlet inside the house (for the entertainment center). This was installed by an electrician back in 2009. Through the garage, the ...
3
votes
1answer
5k views

How can I get a standby generator with GFI to work with a 2-pole transfer switch?

I have a home standby generator that is equipped with a GFI, and my original electrician (who has long since flaked out on me leaving me in a lurch with this) installed a standard 2-pole transfer ...
2
votes
2answers
277 views

Why didn't homeowners get electrocuted when appliances were grounded through the neutral?

I read that appliance at certain times in the U.S. (for example stoves) were grounded through the neutral wire. Since the neutral wire carries current does this means the case of the stove itself is ...
2
votes
1answer
135 views

oven not igniting

(Updated.) I have a gas stove and oven with no pilot light (so they ignite using electricity). The stove and broiler (at the top of the oven cavity) are lighting fine, but the oven is not (at the ...
1
vote
3answers
520 views

What should I look for when diagnosing electrical circuit gremlins where load is much less than capacity?

We have an electrical circuit with these loads (all on different outlets): 15W aquarium pump, 250W LCD television, 35W cable box, 13W GoogleTV box, and a 100W ceiling fan (plus an integrated 50W ...
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2answers
3k views

It is dangerous to have a power outlet run from a light circuit?

Re this answer regarding wiring a garage door power point from a light is this legal I thought it wasn't but just checking. Edit: Legality will depend on location as mentioned in answers, I worded ...
0
votes
1answer
5k views

Why is my Australian light fixture wired this way?

I just want to replace it with a new light fitting philips tcg701 but there's way too many wires and I don't know why it was done this way.
32
votes
8answers
6k views

Which way is up? (electric outlet)

My house has electric outlets in both orientations. Which one is correct? Should the ground hole be at the bottom or the top? OR
19
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4answers
2k views

How can I get a wire that is outside a wall to be inside a wall

I recently removed an abominable drop ceiling from my dining room and found this close to the ceiling on the one side of the room. There is definitely a stud between these two holes. On the other ...