Hot answers tagged

23

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 ...


13

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 the ...


11

tl;dr 15 Ampere cord-and-plug appliances can indeed, safely be connected to 20 Ampere receptacles. A deeper understanding NEMA 6 is a design standard for three wire grounded cord-and-plug devices and receptacles. The number after the dash (-), is the current rating of the device. For example. A NEMA 6-20 device, would be a three wire grounded ...


11

This is a fairly "common" issue, that typically occurs due to high resistance at the terminal. The high resistance can be caused by corrosion, or a loose connection. The high resistance causes heating, which causes higher resistance, which leads to more heating. Eventually the insulation on the wire starts to melt, and/or burn. Usually the heat will ...


9

A subpanel is probably the safest bet. It will allow easier access to cut power in an emergency, and it will offer better protection of the wiring. If you go with option 1, you'll have to step down to #12 or #14 wire at some point to feed 120V receptacles. Which means you'll potentially be able to draw 30 amps on a #12/#14 wire, before the breaker trips. ...


9

I think for what you want to do: temporary short term solution you guarantee you will never operate both the dryer and welder at the same time You could consider building a 220V 30A power strip. Without knowing your welder, I'll list parts from Home Depot that might work but you have to confirm their suitability for your use. Please review this URL ...


9

I'm not in the US, so I used Google to deduce which prong is doing what in this outlet. I'll assume that the left and the right wires are phase wires and the middle wire is the ground. Note that although the left wire looks melted the right one looks just fine although they usually carry equal currents. So this is not melting due to overload. The most ...


8

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 ...


7

I will echo TomG's sentiment: Yikes! By using the BX as the "neutral/ground" (really it's just the neutral; a three-prong 220v plug is considered ungrounded regardless of the continuity that should exist between neutral and ground), whenever the A/C is on, the armor of the cable is energized. It will have a lower voltage than the "hot" because the A/C is ...


7

There should be no problem with opening the box, removing the outlet fixture and then putting wire nuts on the ends of the wires. It may be necessary to straighten the wire ends and trimming slightly if the bare wire ends are too long to be nicely covered by the wire nut. Some folks go the extra step of wrapping the wire nut and the end of the wire with ...


7

If there are two separate duplex receptacles there now Set your multimeter to measure AC volts. Carefully stick one probe in the ungrounded (hot) side of one receptacle (the smaller slot). Carefully stick the other probe in the ungrounded (hot) side of the other receptacle. If you measure 240 volts (or there abouts), then the receptacles are on separate ...


6

Yes. The bigger problem is going to be if any of the equipment requires 50 Hz or is not approved here (e.g., Commercial U.L. or whatever code and insurance requires for a dental lab).


6

You're going to have to either get a washer that accepts 240V, or change the circuit. New Washer Getting a new washer will depend on the manufacturer, dealer, and other factors that are off topic here. Change the circuit Modifying the circuit will require knowledge of electrical safety practices, and general electrical wiring principles/standards/codes. ...


6

To increase the amp rating of your circuit breaker, you almost certainly need to increase the gauge of all the wiring on that circuit. Circuit breakers are there to protect the wiring for overloading, overheating, melting the insulation, and eventually starting a fire. Typically, you have the following wire gauges (this may vary with long circuits and your ...


6

Input Phase Angle and number of transformers needed. For High-Delta, type of transformer. All voltages below are expressed in RMS Average, not Peak... I find it really hard to refer to Split-Phase as Residential or "House" Power. It is used in business where you're not running a lot of heavy motorized equipment. 240VAC Split Phase is produced off a single ...


5

Assuming you mean this 6-30R: After you wire the green (ground, not neutral), it doesn't matter which of the two ungrounded (hot) wires are placed on the 2 'flat' blades. 240VAC (in the North American split single phase) is not polarized with respect to ground, because the neutral is not being used. This connector can also be used with 2 hot connectors ...


5

The calculator you referenced is only appropriate for voltage drop and makes the disclaimer that the results of the calculation do not account for current specs or NEC. Any circuit fused for 30 amps must use a minimum of 10 ga copper or 8 ga alu. Longer runs may require an upgrade of wire size. In your case, use at least 10 copper for your welder regardless ...


5

Yikes! I am not an electrician, but I would run new 10/3 BX. Your jury-rigged system might work, but it has the capacity to electrocute someone, or maybe start a fire, if anything goes wrong. Possible issues include the BX armor being hot if a fault somehow occurs where it's connected to the neutral bus or overloading one of the hot wires if one of ...


5

The panel can indeed support a 240V breaker. The question you should ask is, is there space in the panel to physically accommodate additional breakers? Based on the model number, your panel should look something like this. Notice how this example image has lots of blank spaces. In a panel like this, there's no problem at all installing a new breaker ...


5

If there's no main breaker, then there is probably another breaker box somewhere, possibly in the same enclosure as the meter. Also, it's possible that the panel you are looking at does not have a main breaker at the top; it could be one of the breakers mixed in with the branch circuit breakers. If you can, post a picture of your breaker panel with the ...


5

Everything downstream of the GFCI has to be connected to both the Hot and Neutral from the Load side of the GFCI. The way you've wired it, when the heater kicks on, current is flowing from the Load side of the GFCI through the heater and back to the panel without returning through the GFCI's neutral connection, so the GFCI sees an imbalance and trips. I ...


4

At first I was not sure what you meant. Basically you only want to use one or the other without plugging in and out. Simple answer is No. Not for home applications.. maybe some commercial or heavy industry ones.. but the plugs are different. Not so simple answer.. You can make one :-) You will need a highly rated rotary switch like this one ...


4

Both of the previous answers are completely accurate. New ranges all come with the new four wire plug, however you can convert to a three wire configuration if your box is grounded (in this case your's is) by connecting the ground lug to the box in the female plug. Although this would not meet current code requirements, it is perfectly safe and this three ...


4

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 ...


4

If it switches the mains power supply to the fence charger, yes, of course. If you are using it to switch the energized fence wire, no of course not - that's generally tens of kilovolts, and far exceeds the rating of the switch.


4

TL;DR: Yes, your panel should accommodate the breaker, provided you have space. Quick lesson in North American circuitry. The supply to your house is 240 v, split phase. This means that there are 3 wires coming in. One is 120v, one is grounded, and one is 120 v, out of phase with the first. If we switch our thinking to DC, you could (incorrectly) ...


4

Switching out the cord is easy, but that does not make it a 110V dryer. It's probably not possible to convert to 110V, although you'd have to find a user manual or contact the manufacturer to confirm. And even if you could, it would probably draw more power than a standard residential 110V outlet could supply. The only way to do this is to run a 220V outlet ...


4

Given the 110V tester, I'll assume you are North American locale for this: Look up your outlet type. Test (using appropriate care) that you have 240V from the L1 to L2 (hots) (you presumably did this per your question, but make sure it's the correct terminals) Test that you have 120V from each hot to neutral. Test that you have 120V from each hot to ...


4

That outlet looks like a NEMA 10-20 or 10-50 and is an ungrounded outlet. There are two 120V hot lines and one neutral. This is an old outlet type and is no longer permitted in new installations.


4

Does 240V offer better performance over 110V 240V means less losses in wiring which may lead to better performance at the end of long extension leads. Other than that I wouldn't expect much difference assuming the tools are otherwise equivilent (e.g. you aren't comparing "DIY grade" 240V gear to "professional grade" 110V gear). Is 110V considerably ...



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