63

Send it back right now You bought it off Amazon Marketplace, the world's biggest junk shop. A step down from eBay, even, because this garbage hides amongst legitimate products. Here. See what you had to notice to even spot it? Note the "Sold by some_random and Fulfilled by Amazon" part. That means "Amazon Marketplace" flea market. Often, they also ...


50

It starts with spaces in the panel A service panel has a basic unit I call a space. That's apparent when you look at the "knockouts" on the cover. Electrical power in North America delivers split-phase power. Meaning there are two "legs" or "poles" - L1 and L2 - both 120V from neutral, and opposite-phased so they add up to 240V. Here's an X-ray of a ...


49

In a 120/240V single split phase system, the two ungrounded (hot) legs are actually connected to the secondary winding of the distribution transformer. The transformer actually steps down the voltage to 240 volts, so the two legs are a complete 240 volt circuit. The grounded (neutral) conductor is connected to the center of the coil (center tap), which is ...


26

I bet if you go to your service panel, you're going to find a completely full service panel, and a unique creature we call a "double-stuff breaker". Quite likely the landlord does his own electrical work or pays a dumb handyman (naughty naughty). He's out of space in the panel, so he resorted to those double-stuffs. He moved the dryer from a 2-pole ...


17

Send it back and get something that's listed for the job While what you have is indeed a 120V outlet (the outlet configuration governs, not some text in a manual somewhere), this outlet is not usable in a countertop or work surface in the USA, as it is not listed or labeled for use in a countertop or work surface, as requred by NEC 406.5(E) through (G): (...


17

There's no need to do this for computers/networking gear/... While the switching power supplies used in IT equipment are slightly more efficient when running on 240V vs when they are running on 120V, this efficiency difference is generally small enough that it can be disregarded as a practical matter. As a result, I would simply provision 120V/20A circuits ...


15

It can be done, but you'll have to swap out the breaker. A "standard" US receptacle is rated for 125 volts, and 15 or 20 amperes. So you'll be going from a 30 ampere double pole breaker, to a 15 or 20 ampere single pole breaker. You could install a 15 or 20 ampere double pole breaker, but since you're not using the second line there's no point. In ...


14

Not an immediate danger, but quite a few problems According to the spec sheet, this dryer is rated for 240V, 30A. Running it on "120V outlet" in the US normally means either 15A or 20A. Thanks to Ohm's law, if you run it on a 20A circuit you are probably safe. If you run it on a 15A circuit, there may be a safety issue. But in any case, there are ...


14

For ordinary residential usage, there is generally no need (in the US and other 120/240 areas) for 240V except for: HVAC Electric Dryers Electric Water Heaters Electric Car Chargers Electric Ovens and Cooktops (aka stoves aka ranges). Welders and some other shop tools For most computer users, 240V may give a very slight increase in efficiency, but not ...


13

One possibility is that the two hots, labelled X and Y, are on the same line or leg of the service. The 240V electrical service typical in the US is a three wire Edison circuit, with two of the service wires, commonly called the legs or lines, designated L1 and L2, are at 240VAC at 60Hz, with the neutral tapped midway between the two - 120V L1 to N and ...


12

First you need to figure out the parts you need. Turn the power to the circuit off and remove the outlet. You need to figure out the gauge of the existing wiring. Since it is a 30 amp circuit, the wire should be 10 gauge, so my answer will mostly assume that. Now you can go to the store and buy a 20 amp outlet, a face plate, a 20 amp breaker, and a breaker ...


12

There are a few different issues here: 120 vs. 240 A typical oven for installation in a system like the US (split 120/240) will use 240V for the heating elements (i.e., needs 2 hot wires) and 120V for the controls (i.e., needs 1 hot, 1 neutral). So you can't run it on only 120 or only 240. That is different from, for example, a computer power supply that ...


12

This is a 220V outlet (note horizontal "live" slot on the right): And this is a 110V outlet (vertical "live" slot): Pictures valid in USA. Look at these two outlets. I recently grabbed a 110 thinking it was a 220. There is a difference a 220 plug won’t fit a 110 and a 110 won’t fit a 220. If your 110 plugs fit the outlets you have the will work as long ...


12

Why 30A service? Because of provisioning. They are not able to provision 50A service at this time at this location. That is probably due to transformer or pole-line wire capacity in the neighborhood. Giving everyone 50/60A service means they would be oversubscribing their transformers and pole lines. This would necessitate a big capital expense ...


12

The bigger problem is the transformer is going to set you back about $100, so it spectacularly fails to make sense for a $40 humidifier. Dollar for dollar, if you're coming to North America, you may be better off just adding a couple 240V circuits to your house, and running the appliances off 240V straight shot. North America has both 120V and 240V ...


11

Grounding The bare copper (grounding) conductor is a safety system that provides an effective ground-fault current path, and should only ever have current it in the event of a fault. It provides a low resistance path back to the source, so that a fault can be cleared by the breaker (trip). Grounded (neutral) The grounded (neutral) conductor is a current ...


11

Yes, this does sound like a problem. Assuming your panel is like most, the breakers are on the same phase and you have two problems: No Common Shutoff MWBC is required to have common maintenance shutoff. That means if you turn off one breaker to work on the circuit, the other is turned off too. That is important for safety. This can be done with a handle-tie ...


10

I've labeled your image, to help you understand what's going on. Off to the left, the grounding electrode conductor enters the box and terminates at the grounding bar. The feeder coming in the top of the disconnect has three wires, two ungrounded (hot) conductors, and a grounded (neutral) conductor. The two ungrounded (hot) conductors terminate at the ...


9

No, the plugs are different for different voltages. There are many different NEMA receptacles for various combinations of voltage and current, and also a "twist-lock" receptacles. Some common ones are: (From Wikipedia).


8

Something like a dehumidifier which has a fairly high load and a high start up current, will require a larger transformer. Cost and portability will be major considerations. Smaller appliances with low current draws, will be easier to fit to a small transformer. For reasonable quality transformers, figure a loss of about 3%.


8

Yes, just be sure to run a 4 wire circuit (2 hots, neutral and ground), if the current garage is attached you don't need extra ground rods. In fact, since you are planning for the future, you might install a sub-panel now that would supply your EVSE outlet as well as other circuits in the future. As many others have said here, go bigger than you expect to ...


7

In a 120/240V single split-phase system, there's two ungrounded (hot), one grounded (neutral), and in most cases one grounding conductor. Measuring between the two ungrounded (hot) conductors should yield 240 volts +- 5%. Measuring between either hot and neutral, should read 120 volts +- 5%. In the case of a NEMA 10-30. Each angled contact is one of the ...


7

It's using the earth as a return path You really don't want to do that. Dirt doesn't conduct electricity very well. Your neutral is bonded to ground in your main panel. The power company's transformer also bonds neutral to ground at the pole, and all your neighbors have neutral-ground bonds like yours. The current is trying to return to source (neutral)...


7

Run all four wires Run a /3 cable (hot, hot, neutral, ground) to the receptacle location. For 110, you cap off a hot, and use the other hot, the neutral, and the ground for the receptacle. For 220, you can cap off the neutral and have 2 hots and a ground for a NEMA 6. If you want 110 & 220 together at some point, you can then land all four wires on a ...


7

You are running the dryer without full power, which will drastically increase the time it takes to dry clothes. If you're doing it on a timed basis, your clothes won't get dry. If you use it on a moisture sensor setting, it'll take way longer than otherwise. Additionally, you're using the dryer in a manner for which it was not intended. If it has any ...


7

Of course it's illegal to run power cords inside walls. National Electrical Code 400.8 rolls through the things you can't do with cord, and it's mostly a list of schemes to use them as a substitute for the permanent wiring of a structure. Nope, just nope. Data cables, on the other hand, can go right into the wall cavity. Punch a hole in the drywall and ...


7

3-prong vs 4-prong 3-prong connections lack ground; they bootleg ground off neutral and if neutral breaks, it guarantees the appliance is electrified. Appliance manufactures are terrified of losing sales (or much worse, getting customer returns!) because the installed power was not right for their appliance. That's why they lobbied to allow new 3-wire ...


7

It's funny, how perfectly handy people, who make things all the time, assume nobody makes anything or has Maker pastimes. Atoms are the new bits, as they say. Everything from Burning Man floats to artisan manufacturing are ever more popular. More people than ever are using hooty tooty Euro or quality machine tools like Saw Stop that commonly take 240V. So ...


6

For the second part: clothes dryers often have 240 V heaters and 120 V motors. Stoves use 240 V for the elements and 120 V for the light bulbs. These are both plug-in and need the neutral. My new electric hot-water heater is 240 V, not plug-in, and uses the old 120 V wiring. The electrician doing the install marked the "old" neutral with black tape at ...


6

My previous answer was a bit unclear, and a bit misleading. So I'm going to take another stab at it. As before, we'll start by looking at the secondary side of a single split-phase transformer. And again, the loads are represented by purple rectangles. Then we'll spit the circuit up into individual circuits, so we can take a closer look at each circuit. ...


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