I live alone in a two bedroom townhouse with a full but unfinished basement. My rent is about to increase to a painful amount, so I’m trying to figure out a way to move my computer equipment from the second bedroom into the basement to allow for a roommate, but there are no wall outlets there. So since I can’t afford to have an electrician come in and install some outlets, I’m left with few options, which I think are:
– Use those outlets that you screw in to overhead light sockets. But I worry that this wouldn’t adequately support the 850 watt PSU on my computer.
– There’s a 120 v standard outlet on the wall with two plugs that are being used for my washer and dryer. However, they both have labels that warn against using an extension cord (or power bar, I assume), which means that I can’t use that. Or can I safely ignore the warning on at least one of them? It’s a gas dryer, so electricity is only used to spin the drum and other minor things like the timer. Perhaps I could use that plug?
– There’s an unused socket in the same location that I assume is for electrically heated clothes dryers. The face has three slots arranged in a circle, and the top slot is notched. I tried finding one that matches that arrangement in Wikipedia, but I had no luck. I assume it’s a 220/240 volt outlet. If so, there are step up/step down power converters of various wattage that I could buy. I imagine that I could then connect the 120 v output of the converter to as many power bars in series as I needed, correct? The PSU is 850 watts, but there are other devices such as a printer and two external hard drive enclosures, so I figure I would need at least 1500 watts. Does that sound right?
The computer in question is my media server, so it’s always running. I assume that the converter would unavoidably waste power as part of its operation, compared to using standard 120 v outlets. Would you think that would waste a significant amount? Because my electrical bill is already very high, at least during warmer weather.
Sorry if this post was too long, but I always strive to include enough info for folks to help me out. Please share your thoughts…
First, what you’re looking for is a NEMA chart. That’ll show you pictures of all the different outlets.
However, unless you plan to rewire one so it can accept a normal 3 prong, 120v plug, I’m not sure it matters.
Also, the light socket adapters are only going to be two prong since there’s no ground in the socket (the actual part where the bulb screws in.
I’m not sure why the outlets you’re talking about would have labels telling you not to use an extension cord. I can only assume it’s so you don’t put the washer or dryer across the room and run a load that large with an extension cord instead of the large one they provide you.
Personally, I’d just use one of those outlets and a cord to your computer.
Now, 1500 watts is a lot (it’s 12.5amps). If you’re really going to be drawing that much current, I’d use a bigger extension cord. Go get one rated for 15 or 20 amps. They can be expensive, but it’s better than an overheating cord or a constantly blowing breaker.
Ceiling light circuits are often <20 amps in older buildings, and there may be other outlets connected in other rooms, reducing the available capacity.
None of your ideas sound safe to me. If you decide to do this, make sure your insurance covers accidents, but non-code wiring will probably invalidate any insurance. And get a fire extinguisher rated for electrical fires. And an alarm system.
The dryer outlet should be one in this picture. Can you tell us which one?
Your computer PSU can almost certainly take 240V directly, though you should check your manual to be sure. If so, you should be able to find a cord that goes directly from the outlet type to your computer (a C13 connector).
You have other devices, but they are lower powered and you could likely run them from a light bulb converter separately.
Note that your computer doesn’t actually draw 850 watts all the time. In fact it’s very unlikely that it ever draws that much. You may want to get a power meter (kill-a-watt, etc.) to see what your actual load is.
The unused electric dryer socket is probably a 10-30, very common older style for dyers. It’s two hots and a neutral. No ground.
You don’t need any sort of electric converter to change that socket’s 240 to 120. If you were in Canada, there are plug adapters that connect the neutral and one of the hots to a standard outlet. They’re primarily used with gas ranges to power the clock/electronics, but they are not “legal” in the US.
Next option is to have an electrician rewire the dryer circuit from 30 amp 240 volts with no ground to a 20 amp 120 volt line. This involves some trivial (to an electrician) re-arranging of wires in the breaker panel, changing the double 240-volt breaker to a single 120-volt breaker, and a little adapting of (probably) 8 gage wires to 12 gage wires that will fit under the terminal screws on a standard outlet. This really is a simple job - if you were a friend, this would be a “parts and beer” kind of thing.
What Dr Strangelove said is my experience too. The desktop PC power supplies have a toggle switch that can be set for 220v or 110v. Laptop power supplies, phone chargers etc auto adjust.
Also like pointed above, I doubt your setup withdraws more than 100W continuously. You can tell it from your power bill also.
Most desktop PSUs auto-adjust these days as well. An 850W PSU is likely to be recent enough to be in this category, but one should always check. There should be a table in the manual somewhere that tells you the input voltage, and if it’s auto-adjusting it’ll say something like “90 to 250 VAC”.
None of my recent computers uses a 3-prong cord anyway. In fact they don’t even use a polarized plug. Using one of those lamp socket adapters should be fine. You can look at the plug on the computer and see what kind it is.
Are you talking about a laptop or computer with external brick power supply? I can’t think of any desktop-type computer whose power supply is ungrounded. In any case, desktop power supplies and computers are designed with the expectation a ground will be connected for shielding and EM noise reduction.
The real solution here is to get an electrician in to install proper power outlets. Your landlord will probably let you do it if you foot the bill, and may even pay a portion themself (since it increases the value of the home for the next renter).
And not on the electrical question, but also double-check that your lease allows subletting, and that your local housing code allows basement occupancy.
Yes. Two hots and a ground, no neutral. Ground for safety, two hots for 240. You don’t need a neutral since the two hots are out of 180 degrees out of phase.
Something I try to keep in mind is that if I’m putting in a 240v outlet, to just run a white wire as well. That way, should I need it down the line, I’ll have 120 available at the outlet.
Are you allowed to tap into a 240 V (with neutral) circuit and install a 120 V receptacle? I’m pretty sure this would be against code, since the double-pole circuit breaker will probably be rated at 30 A or more, and the wiring to the 120 V receptacle will be 12 AWG or 14 AWG. I guess it might be legal if the wiring to the 120 V receptacle is the same AWG as the 240 V wiring (10 AWG or 8 AWG or whatever).
I’m not 100% sure on the code. Off the top of my head, code might say you can’t have a breaker more than a certain percentage above what the outlet is rated for, but don’t quote me on that.
But it’s still nice to have the neutral available. Even if you keep things in code, it still gives you the ability to replace the 240 with a 120 outlet and put in a smaller, single pole breaker (as well as another outlet on another breaker since you have the wire). Also, should you need to, you can turn the 240 into a 120/240.
Since we’re in the US, the wiring for a 120v outlet will almost always be smaller than the wiring for a 240, so you’ll be good there.
It’s just a nice convenience for future proofing. It’s usually easier to push 4 wires now rather than 3 wires now and 4th later on. Even more so if you use Romex and it would mean starting over.
Luckily, it’s not like this comes up often, but I’ve had cases where I was kicking myself for not doing it.
If that’s the only outlet on the circuit, then just pop in a dual 15 A breaker. No need to do anything about the wiring.
gotpasswords is correct. 10-30 is in fact hot-hot-neutral, with no ground. L6-30 is hot-hot-ground.
Of course the dryer still needs a ground. Ideally you would ground the case to a separate wire, or a grounded conduit, or a water pipe, etc. But in practice it was frequently just tied to the neutral, which isn’t great for electrical safety but used to be allowed by the code.
A 6-30 receptacle works better for the OP’s purposes, as he can simply get a 6-30 to C13 cord. It may better fit the “circle” description from the OP, though maybe I’m taking that too literally, which is why I asked.
If it actually used 1500 watts, it would be like having a 1500 watt (1K5) heater in the room. It’s not like that: it’s more like having a 200 - 300 watt bulb in the room.
A 350 watt heater bulb is more than I would use in a normal lighting socket, and I don’t recommend that.
A problem with using an extension cable in a power socket is that, particularly in the USA, a short circuit at the end of a long cable may not immediately trip the fuse. And this is even more particularly a problem outside or in the basement, where stuff may get wet. I wouldn’t have an problem ignoring that, using a heavy extension cord, and mounting the extension cord carefully. Doing so would be illegal in Australia (where all mounted wiring has to be done by an electrician), but I’d do it anyway.
I wonder about using the dryer socket. Are desktop computer power supply units typically fused on both the active and neutral? Is there an American standard for that? Don’t you have a problem with random wiring of active and neutral anyway? And if so, how do you deal with that?
And I should nitpick myself here. If you run two hots, from two breakers with a single neutral wire, along with a few other things that need to be done, you have to have a double (DPST) breaker. Since the neutral is shared, you have the potential, in certain circumstances to have a hot neutral, this eliminates that by killing both circuits when you flip the breaker.
Also, just to make things more spicy, if you have a shared neutral and lose your neutral, things plugged are going to operate at 240* volts, until they let the smoke out.
*Kinda, it’ll less than that due to resistance from other things plugged in, since everything will now be in series instead of parallel.
What do you mean by random wiring? Sure people make mistakes or don’t know what they’re doing, but that must happen everywhere. On the assumption that you’re talking about not know which wire is which, we do, like most everywhere else, have codes that dictate what colors mean what. In general, green/copper is ground (earth), white is neutral and Red or Black is hot (active?). There’s some variations on this, but if you look at the wiring in most homes (single phase, 120/240) in the US, it’s what you’re going to find.
