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Questions tagged [electrical]

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. Posting photographs of wiring junctions or drawing a wiring diagram and posting it is also highly recommended.

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13
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1answer
59k views

What is the correct way to wire a 4 prong oven receptacle?

I think I wired this the right way but I can't find an online reference that I trust enough to flip the breaker back on. This is how I wired it. Is this correct?
13
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1answer
2k views

Can cable splice devices be concealed?

Devices exist that claim to be able to splice nonmetallic sheathed cables together outside of a box, and in concealed locations. Are these types of devices allowed by National Electrical Code? Here's ...
12
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4answers
5k views

How to cut off and insulate live 3-phase power?

I need to disconnect my 3-phase cables from the power pole to my house. I'm building directly under it and though the contractors say they are okay with it, I would prefer to disconnect for a week or ...
12
votes
3answers
6k views

Does a 2100W angle grinder need an earth pin?

I have recently purchased a Makita 2100W angle grinder. It has just the live (L) and neutral (N) connectors unlike the one I previously used, which had a third protected earth (PE) connection. Would ...
12
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6answers
3k views

Easy way of generating a 50-150W load @12V

I need to test a battery for its remaining capacity and to do that, I need to generate a constant load to be able to measure how long it can sustain that load. I tried using a 330W load (290W shoe ...
12
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5answers
9k views

What kind of gloves should I wear during electrical work?

What kind of gloves should I wear during electrical work? I need to know which glove material is most suitable for this kind of work, as I wish to purchase the proper gloves.
12
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4answers
3k views

Can a GFCI outlet intentionally and explicitly be used as a switch without violating code?

I'm working on adding several outdoor outlets in the eaves of my roof for holiday lighting. I have a switch in my garage for these outlets right next to the garage light switch. Thing is, I keep ...
12
votes
7answers
76k views

Can I plug a generator into a dryer outlet [duplicate]

I have an electric dryer with a 30 amp circuit running to it. If I had a male-male plug to run from a portable generator to this outlet, would it be safe to run essential appliances (water pump, ...
12
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7answers
66k views

Is Switching the Neutral OK?

What’s the worst that can happen if i put a switch in the neutral instead of the phase? I just found out that 3 light bulbs sockets in my home are connected this way, it first came to my mind to ...
12
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4answers
3k views

What is this 110/24V 60Hz transformer in the breaker room for?

My friend sent me a photograph of this transformer, which is installed above the main breaker panel, with leads running from the panel into the transformer. The stamped labels read PRI. Volts: 110 ...
12
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2answers
3k views

Can I use a neutral wire from another outlet to repair a broken neutral?

Recently one wall of outlets quit working. Testing shows the hots are all good and the grounds are all good but the neutrals are all dead. They are all connected to each other but somewhere have lost ...
12
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3answers
24k views

What are the differences between these two receptacles?

Residential duplex outlets come in a variety of styles. The two most common seem to be: and Does it matter? Is the difference purely aesthetics, or is there any technical difference?
12
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3answers
2k views

What is “knob and tube wiring”?

I assume this is some USA wiring system, am I right?
12
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5answers
3k views

What is the industry term for house wiring diagrams?

I am doing electrical work in my own home. Primarily replacing old sockets and fixtures. Through the course of this work I am finding odd, but not unsafe, wiring paths. I want to document these paths ...
12
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4answers
11k views

Why is this shared-neutral wiring bad?

Summary: I have this wiring situation in my home. I gather it's not up to modern code, and I experienced why it's bad (got shocked), but I don't understand why (physics/electricity) it happened. In ...
12
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4answers
3k views

Are rechargeable 9-volt batteries suitable for use in smoke detectors?

Lithium-Ion rechargeable 9V batteries are now readily available. Are they appropriate for use with hardwired smoke detectors, which typically use 9V batteries as battery backups? What about for use ...
12
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3answers
7k views

Is this electrical junction up to code?

I was up in my attic a few days ago, and I noticed a pretty ugly electrical junction that wasn't in a junction box. Here's the pic: Is this up to code? FWIW I live in north Alabama, outside city ...
12
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5answers
24k views

Does turning circuit breakers off cause wear?

A comment over on another SE got me thinking. With screw-in fuses, unscrewing it and then later screwing it back in causes negligible wear on either part of the installation. But what about modern "...
12
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5answers
16k views

Why do my new dimmable CFL bulbs hum?

I just spent $100 upgrading our dining room lighting from regular incandescent bulbs with a dimmer switch to a CFL friendly dimmer switch with specifically marked dimming capable CFL bulbs. At full ...
12
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7answers
68k 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 ...
12
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6answers
166k 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 ...
12
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10answers
118k views

How can I run Cat5e cable through a completely finished house?

My family and I are interested in buying a house that was built in 2002. This house is two floors on a concrete slab with a finished bonus room upstairs so there is no attic other than above the ...
12
votes
1answer
20k views

How exactly does a 3-way switch work?

I just finished replacing all of the switches and outlets in my apartment, after fighting a long war with a weird 3-way switch. Needless to say, I won, but I'm still trying to grasp the concept of how ...
12
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4answers
4k 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 ...
12
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10answers
161k views

Why would a GFCI trip on refrigerator circuit?

My refrigerator is tripping the GFCI on the socket into which it is plugged. Searching about this topic seems to indicate that this is a reasonably common complaint. However, I can't find any ...
12
votes
1answer
621 views

How to make this electrical main safe

An older home has a strung electrical main. The main connects with exposed lugs on the roof above the deck. Not only is the height and location unsafe, while working on the roof today I noticed that ...
12
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5answers
851 views

Installed Electric Tankless Water Heater - Internet loss when active

I installed an Ecosmart 27kw tankless water heater yesterday and as far as heating the water goes, everything works perfectly. The issue is when the water heater is running, I lose internet! Specs: ...
12
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6answers
41k views

Is “don't mix data and power cables” and “don't loop power cables” still valid nowadays?

There are two sayings I keep hearing when talking about wiring e.g. home cinema or computer hardware; Don't wrap data/network cables and power cables up in the same loop because the power cables will ...
12
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2answers
4k views

Was it ok to add an outlet on a home run in the attic?

I had the following setup for a room, running on 15A breaker with 12/2 I wanted to add an outlet in the attic above this room so I did this: There was enough slack in the wire, so I added the outlet ...
12
votes
2answers
2k views

Is it acceptable to have two circuits with a shared hot but different neutrals?

I am working on cataloguing the hodge podge electrical system in my old house. There is an old fuse box that was converted to a junction box when they put the breaker box in. Inside this box there is ...
12
votes
2answers
9k views

Can disconnected knob-and-tube wiring be left in place?

The house I recently bought (over 100 years old) has had almost all of its wiring replaced with a new elctrical board. However, in two cases the new wiring has been connected to existing knob-and-tube ...
12
votes
2answers
15k views

How can I replace 2-prong receptacles in a code compliant way?

I have some 2-prong non-grounding type receptacles, and I'd like to replace them with 3-prong grounding type receptacles. According to National Electrical Code, what are my options?
12
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3answers
487k views

How to connect multiple light fixtures to one switch?

I am remodeling my basement, currently I have 5 light fixtures and each one has its own switch. I would like to make it so when I turn on the switch at the bottom of the stairs all the lights turn on....
12
votes
2answers
7k views

Can I change a 1-gang electrical box to a 2-gang electrical box?

I live in a house built in the 50's in Maryland, US. Each bedroom contains 4 electrical outlets - configured in two 1-gang electrical boxes on opposing walls. However, with all the modern appliances,...
12
votes
1answer
12k views

Running cat 6 networking cable in the attic: what is up to code?

I plan on adding a Cat 6 network in my single-story detached home. It would consist of home runs from each of the 3 bedrooms + TV room to a central patch panel in the garage, which is close to the ...
12
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6answers
42k views

Why is ENT rarely used for electrical wiring?

As best I can tell, the National Electrical Code 2011 allows electrical non-metallic tubing ("smurf tube" or ENT) to be used for running 120 V electrical wire. But everywhere I look, I see remarks to ...
12
votes
2answers
142k views

How do I properly ground my subpanel that only has one neutral/ground bar?

I am adding a sub panel in an unattached building. My sub panel has the connection for the 2 hot wires coming from the source panel (a 40 amp double breaker) In addition it has one neutral/ground bar ...
12
votes
1answer
13k 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 ...
11
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8answers
19k views

Can I put an outlet inside of a wall?

I want to mount a tablet to a wall with a charger but I don't want the charger to be visible. Can I put a normal wall outlet in the INSIDE of the wall and just plug in the charger inside the wall? ...
11
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5answers
27k views

How can I trip a breaker from the outlet

One time at my job we had some electrical work that needed done. The electrician had a small homemade switch box with a 120v mains plug running out of it and a switch on the front. The device ...
11
votes
3answers
29k views

Turn one light bulb ON and another OFF at the same time with one switch

I am trying to operate two AC current light bulbs with one switch so that while the switch is in the OFF position, bulb B1 is OFF and bulb B2 is ON, and while the switch is in the ON position, bulb B1 ...
11
votes
8answers
28k views

Is there any legitimate reason you would NOT connect the ground wire on a circuit?

I've been doing some remodeling on my house and had the need to move some electrical outlets. While doing so, I noticed that the ground wire wasn't hooked up on any of the outlets in the circuit (...
11
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3answers
4k views

What are these (utility?) boxes at the side of the house?

What are the four boxes in the picture below for? The fat pipe to the left goes up to the electricity meter. I've also included pictures of the two labels I could find. Also, why is there a green ...
11
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3answers
4k views

Wiring IKEA light fixture into old fixture

I am installing a simple IKEA ceiling light fixture. The new light fixture has a neutral wire, a live wire, and a ground wire. My current old light fixture has 4 wires: white, red, dark blue or ...
11
votes
10answers
72k views

Does one need to be certified in order to do residential electrical work?

I have a Bachelor in electrical engineering, a lot of hands-on experience with electrical work, and I'm very familiar with NEC 2011 and electrical codes. Can I do residential electrical work without ...
11
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7answers
19k views

Why do electricians prefer not to use the push-in connections on receptacles?

Why do electricians prefer not to use the back-stab or quick connect holes on switches and receptacles? If these were unreliable do you think they would be allowed by the NFPA and NEC?
11
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3answers
3k views

Can ground attached to neutral fool a receptacle tester?

I'm using a basic outlet tester like the one from picture below. Let's say someone wired the ground to the neutral in some outlet, to provide a fake ground. What would the tester report? Would it be "...
11
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3answers
15k views

Is it possible to be electrocuted from a properly functioning GFCI circuit?

It's my understanding the the purpose of a GFCI circuit is to prevent shock by tripping the circuit if there is an imbalance in current in vs. current out. So my question is, if you have a functioning ...
11
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6answers
139k views

Can I connect copper wire to aluminum wire?

I'm installing additional light bulbs in my basement. I have an older house with aluminum wiring. Can I do this: [new light bulbs]<--copper-->[old light bulb junction box]<--aluminum-->[main ...