Ask MetaFilter questions tagged with electric

where do these wires go?

crazylegs — Sat, 26 Dec 2009 07:03:06 -0800

I'm wiring NM-3 cable into a fuse box. Where do the wires go? I'm putting an NM-3 cable into a fuse box. There are four wires: bare, white, black, and red. I know the bare is ground, the white is neutral, and assume both the black and red are live. I know where the ground, and neutral go. The black is attached to a fuse, is the red just attached to another fuse? Note: this isn't a 240v circuit.

Verifying a Wurly Piano is in fact Where It's At

elektrotechnicus — Tue, 22 Dec 2009 00:58:13 -0800

I might be able to purchase a Wurlitzer Electric Piano (looks like a 200A, but with a speaker cabinet supporting it) today for ~$450. This strikes me as a really great deal, and therefore just a bit suspicious. I'm obviously going to try every key (for both sound and feel) and make sure the tremolo knobs are working. What else should I look out for? Are there any potential defects which might not be obvious at first glance? What degree of disrepair should I be willing to accept at this price? It seems like the biggest issue will be reeds, but based on a cursory googling they seem to be pretty easy to tune (I'm pretty handy with a soldering iron and file). Is this harder than it looks?

Bonus Question: Will I be able to remove the piano from the speaker cabinet, or were some of these made as one big inseparable console?

Help me fix my G string!

metajc — Mon, 21 Dec 2009 07:55:57 -0800

Can I get my guitar fixed so that my G string is in tune with the other strings both when fretted or free-ballin? I have had a Hondo Deluxe Series 750 electric guitar since 1993. I bought it for $80. It's probably an awful guitar but it is now a part of me. I've never had or wanted another electric guitar.

The problem is the G string sounds in tune with other strings when it's played open but off when fretted. If I tune it so that it's in tune when fretted, it's out of tune when open. ACK!

I've asked a good guitar store tech if he could fix it and what the problem was but he wasn't sure.

It has pretty "normal" tuner posts, little hooks for holding down the string at the head, a plastic nut, and Dimarzio bridge that pulls the strings to the back of the guitar ... action is perfect. It's like a strat.

How do I get that G string in tune? If it's too hard to tell, please direct me to some guitar maintenance websites where I might learn more.

UPS and battery reference on the large scale

thewalrus — Thu, 17 Dec 2009 05:04:11 -0800

I would like to learn more about large-scale UPS systems, particularly the battery strings used in traditional RBOC/Telco applications. These are the sort of beasts that use huge strings of 6V 220aH deep cycle batteries, or even large numbers of 2V 400aH batteries on very strong earthquake-resistant shelving wired up to create a 48V mega-battery. Can anyone point me to the most definitive reference materials on the subject?

Don't give me that jargon.

mearls — Sat, 31 Oct 2009 11:35:32 -0800

Do I need a rotary phase converter or a variable frequency drive for my three phase bandsaw? I just bought a beautiful 36" Oliver bandsaw from 1905. Naturally, it has a three phase motor and there is no way we are getting three phase power out here.

I've ruled out a static phase converter since I don't want to lose a third of the horsepower so my options are as above.

I understand what the RPC does and think I know what the VFD does. The former generates a new leg of power which doesn't seem terribly efficient. The VFD, I think, digitally splits the 220 into 3 phase 220 which is what the motor needs.

Is there something about the VFD that I don't get? Why does my fathers electrician friend say that "they are very specialized. You don't need it." I actually think I do, and when my massive lathe comes in I will definitely want the VFD to control the speed.

BTW, at no point will I be using both bandsaw and lathe simultaneously.

Need a solution to keep my sisters feet warm in ski boots.

no bueno — Sun, 18 Oct 2009 13:15:48 -0800

Need a solution to keep my sister's feet warm in ski boots. My sister has Raynaud's syndrome so whenever we go skiing she has to take constant breaks to go in and warm up. This year she's trying these Swany mittens that have an insert for handwarmers. We tried footwarmer inserts but her feet suck all the warmth out of them within minutes. I think she's going to need something battery powered but everything I've found online seems like it might be cheap(quality not price). Suggestions. Remember this is for skiing, socks would need to fit in the boots, so I'm guessing insoles might be the best bet?

Please help me build a motor scooter!

banished — Wed, 09 Sep 2009 15:32:13 -0800

Can you help me build an electric motor scooter? I have a bunch of old bike parts in a garage, so I should be able to put something together. I found a simple explanation here, but what I am looking for are specifics on where to get each of the materials (especially the motor, the batteries) and how the batteries should be wired to the motor and details on any power regulating circuit that needs to be built.

This is intended for a little kid, so whatever I build needs to be safe, and not TOO powerful.

How do I best make an outlet in my baseboards?

notsnot — Sun, 06 Sep 2009 06:58:36 -0800

How do I make an outlet in my baseboards? I'm re-wiring the bedroom due to an untraceable short circuit (yay...came home from vacation to no power in the bedroom) and have decided that installing outlets in the baseboards is the best way to go. But, um, the outside wall is brick... The house is typical, all-brick construction from 1931. There are no outlets on either of the two exterior walls. I would like there to be. (actually, when I bought the place, there was a metal box with an outlet nailed to the floor. However, surface-mount boxes are deeper than my baseboards. I *think* the best option is to just mark the box location, then plunge the trusty roto-zip into the baseboard, plaster, and brick behind. I'd like to avoid pulling the baseboards again.

Bonus: the boxes have inlet tabs on each of the short sides (the ends). But mounting them horizontally would have the outlet be on the side, not facing down, which would be better for connecting to the wiring in the basement. Do I just wallow out a bigger hole in the baseboard and run the wire so it makes a right turn (downward) once it's out of the box?

Good cheap flexible exectric piano?

singingfish — Sun, 19 Jul 2009 23:02:31 -0800

What's the best value second hand electric piano I can get? My requirements are full sized weighted velicity sensitive keyboard, and midi in/out cables. Maximum budget is AUD400 (USD 325, GBP 200, EUR 230). The Yamaha DGX-300 looks good apart from the floppy disk midi interface. Are there any other options about the same price/quality?

Bzzzzzzzzzzzzzzzzzzzzzzzzzzt

spamguy — Wed, 15 Jul 2009 19:48:51 -0800

As a lifelong manual shaver, I'm giving electric shaving a try. What should I expect? When I shave, I am all about closeness. If I feel a hair on my face, there will be problems. I tend to switch back and forth between double-edged and safety razors, depending on my mood. Especially with the former, the aftershave hurts like a mofo, but I get the closeness I seek. I tend to tear up my lip.

My girlfriend insists on getting a respectable model of electric shaver as my anniversary present. She felt I was not being as kind to my face as I should be. I have a few reservations about making the switch. How does electric compare to manual? What can I do to maximise closeness? Screw safety. I mean, if it doesn't work out, it can be returned and replaced with a different model, but if electric cuts corners (heh) with shaving, no amount of trial and error will help.

My fridge freezer defrosted over the weekend, will my insurance cover this?

Sevenupcan — Mon, 29 Jun 2009 03:36:51 -0800

I've come home to a defrosted fridge freezer and all my food has defrosted. Can I claim this on my home insurance? I went away for the weekend to see family and found all the food in my fridge freezer has defrosted. I'm a little worried that my electricit company may have cut my electric over the weekend because of a mix up and think this may be the cause. Otherwise my fridge is acting up and defrosted itself over the weekend.

Is there anyway to tell if my electric was cut? Is there a way I check to see if my fridge is working alright? Some of the food I fine, but a lot of it is no good now that it's been defrosted for a couple of days. Is there a way I can claim this on my insurance?

Thanks for your time and help.

Cheap, online electrical retailers in france?

handee — Mon, 08 Jun 2009 07:51:44 -0800

I'm in France, and I need to buy a washing machine, and maybe a TV. I am going to need it/them delivered. Can anyone recommend an online retailer? Cheap is good.

But I need a three prong!

dithmer — Sat, 09 May 2009 10:03:29 -0800

I just moved into a new house - it's Victorian, so there's some older technologies and stuff around here. On the wall closest to where I have my television, DVD player, DVR cable box, cable modem, Airport, and Nintendo 64, there is only a 2 pronged socket. Already I'm only using extension cords, but not only am I going to run out of room, it's not grounded. So what is the best way to adapt? Do I get a 2-prong to 3-prong adapter, and if so, can I plug a power strip into it? Do I try and find a 2-prong power strip? Or do I ask the landlord if she can hire someone to change it? Is this expensive/complicated? Thanks!

Disherwasher vs. hand washing

markcmyers — Fri, 10 Apr 2009 10:18:25 -0800

Dishwasher vs. hand washing. Assuming we run the dishwasher only when it's full, which method uses less water and fuel?

Electricians! Craftspeople! Help me build a box that gets hot!

segatakai — Thu, 12 Mar 2009 08:53:02 -0800

I'm looking for any suggestions as I'm trying to make a new, improved version of a box my professor built by hand 30 years ago, which has two stainless steel surfaces which get hot. His box is bigger than I need and not as spiffy as I'd like. I want to make a box. The box should be approximately 14 x 20 inches; the depth is as small as is safely possible (presumably no less than 4 inches, but the smaller the better). The box is made with a wooden frame, and stainless steel sheeting on the two large sides, attached presumably by screws. The box will stand upright on its smallest surface. Inside the box is (are) something to heat up the air inside of the box, and the stainless steel surfaces, so the outside surface can reach approximately 50 degrees Celsius/120 degrees Fahrenheit (less than 40/100 would make the box next to useless, and more than 60/140 is too hot). The surface should reach this temperature within 30 minutes of being plugged in/turned on, more preferably 10 or 15. The stainless steel surface should be as evenly heated as possible, with no/limited hot or cool spots. On the side of the box is a dial/dimmer which allows the temperature of the surfaces to be controlled. The box plugs into a regular outlet. The box does not explode or burn or hurt the people who are using it or near it. The box can be made by someone with very basic but not special electrical knowledge from parts available in-store or online. The cost of building the box (not including the stainless steel) does not exceed $100, or at a stretch, $200.
- What are the things (thing) inside the box that produce the heat? Are they light bulbs? Heating elements? Ceramic "bulbs"? Aquarium heaters?
- How is the temperature controlled? I'm gong to have to put a thermometer in there, right?
- What keeps the heat even across the surface of the box? Insulation? the nature of the thing producing the heat? some other material placed on the inside of the stainless steel sheets?
-What keeps the box from blowing up or burning?
In case it matters, the box will be used for drying sheets of handmade paper.
Any thoughts/suggestions will be very much appreciated!!

It's not a Tune-ah!

bondcliff — Wed, 11 Mar 2009 06:34:32 -0800

What would cause my electric guitar’s high E string to fool my tuners? I have a Mexi-Strat that plays pretty well but I can’t get the high-E string to tune properly with a tuner. My ears aren’t that good so I pretty much always use a tuner to tune the thing. All the other strings tune fine, but when the tuner shows the E string as “in tune” it’s actually sharp by maybe a quarter tone when I compare it to the B string. Even with my poor ears it’s obvious to me that it’s way off. The facts:

It’s not the tuner. I’ve tried three different tuners (a POD, a Mac, and a Boss Tuner) and it’s always the same. These same tuners work fine on my acoustics.

Switching pickups doesn’t seem to help, nor does adjusting the volume or tone.

It’s not the B string that’s out of tune. If I compare B to G it’s fine. It’s definitely the E string that is off. The low E string tunes fine.

It’s not the intonation. I’m tuning the string open. I don’t think it’s a matter of it needing a setup.

It’s not a matter of being in tune at the attack and then getting out of tune a second later. It’s out of tune from the get-go and stays there.

New strings or old stings, the problem is the same.

It's not the cables (I've used different ones) and there are no pedals or other devices in the chain. Just guitar, cable, tuner.

All other aspects of the guitar seem fine. It's not damaged, at least externally. It plays well, it sounds good when it is actually in tune.

Really, it seems like it’s not a physical thing at all, but somehow the frequency is getting higher within the electronics, if that makes sense.

Space Heater Improvement

gzimmer — Fri, 06 Mar 2009 01:44:00 -0800

I have an electric space heater that makes a mild burning smell and the fan makes too much noise, any ideas on how an adventurous engineering student might be able to make the unit better than out of the box? I have this unit specifically. There doesn't appear to be anything solid inside (as seen through the grill) that might be causing a burning smell, and I have no idea where the fan even is. I have a few assorted enthusiast grade computer fans that might be quieter, but i have no idea what to expect once I crack the case.

I have no clue...

Eringatang — Wed, 04 Mar 2009 20:08:35 -0800

Please help me identify these electrical thingies in the house we are buying. We are buying a house built in 1980. There are two electrical-looking thingies and we don't know what they do--neither do the home inspectors, current owner, nor the electricians that we have asked. Please help!

Mystery thingy #1
It is a "green" house from the 1980s, with passive solar heating (internal brick walls heated by sun through southern-facing windows) and it also has two fireplaces. It is possible that these fireplaces were an integral part of the heating system at some point. There is a box attached to the wall next to the basement fireplace. It looks like this inside. What is it?

Mystery thingies #2
These black-and-white capsule-looking thingies are under the porch. There are kennels under the porch, and there is a sprinkler system in the back yard. It is possible that the thingies have something to do with these, but also possible they are unrelated. What the heck are they?

Help make sense of my house's gas bill

rachaelfaith — Tue, 24 Feb 2009 09:09:05 -0800

What is wrong with the electric and gas in my two-family house? Our bills are incredibly lopsided. Some background information: I live in a big ol' college house in New Brunswick, New Jersey. The house has three floors- the first floor is one 'apartment' and the second and third floors are the second 'apartment'. There is a large basement.

Our heating and electric bill has skyrocketed this year. This month, we were asked to pay $803.65 for gas and $144.28 for electric, for the occupants of the second and third floors.

The first floor's gas bill was $54.00.

We keep our heat set to 60 degrees in an attempt to keep the bill down, and they keep their heat at 72. We use space heaters to make it comfortable, but we're not as concerned about that since the gas is the part that is astronomically high.

Things we found out:
1. There is only one boiler for all three floors and we pay for it.
2. They have forced air heat and we have steam heat.
3. We pay for heating the very large basement where there are two broken windows. (Asked the landlord to fix them and they were simply boarded up)
4. We pay for the washer and dryer, which is accessible to all occupants of the house.
5. PSE&G cannot look at the boiler and such because they did not install them.

What recourse do we have here? Our landlord is pretty much throwing his hands up at us and saying he doesn't have to do anything, even though the house's floors aren't equally equipped and the bill is not shared correctly.

We called an electrician today to look at the house, but I'm not really sure what to ask them. Suggestions?

I am at the end of my rope trying to sort this out between PSE&G, my landlord, and the residents of the house.

Help!

Does grandma need an electric submeter?

letahl — Sun, 22 Feb 2009 16:49:52 -0800

Help my grandma lower her utility bill by installing a submeter for the downstairs tenants. My 77-year-old grandmother unplugs her appliances to eliminate ghost loads, doesn't keep bulbs in all the lights, and keeps the heat at 68. But she keeps getting ever-increasing electricity bills. This month her bill was $540. Meanwhile, her friend lives in the same townhouse complex, across the parking lot, in a bigger house, with her husband, and they keep the heat high, leave all the lights on, and run a full-fledged office out of the basement (5 computers, which she never turns off). Her bill for the same time period? $360. It's like this every month, with my grandma's bill around 1/3 higher, with no obvious reason why.

The only explanation that I can think of is that Grandma has a couple living in the basement apartment. They do have a range top and refrigerator, a tv and computer, bathroom with heat lamp, but that's it. No space heater, so they say, and it appears from her occasional impromptu visits downstairs that this is true.

Grandma's in the suburbs of DC, and electricity is running about a dime a KWH. She had her heating system checked out and the tech said it was fine. I bought her a Kill-a-Watt last year and she goes around testing everything trying to figure out what is wrong. I am trying to convince her to get a submeter for the tenants downstairs. Maybe its NOT them, but I feel the more variables you remove, the more progress you are making.

So, here are my questions. I see that submeters run around $250 online, but how much is it on top of that to get one installed? Also, given the facts as I've described them, is there any other course of action you would recommend? These bills are really hurting her.

Thanks, Mefites.

The inconceivable nature of nature

Eiwalker — Sat, 21 Feb 2009 11:41:38 -0800

How much do criss-crossing electromagnetic waves affect one another? Richard Feynman famously said this:

http://www.youtube.com/watch?v=AU8PId_6xec

The picture is that the electric field consists of a lot of jiggling, and that information is going every which way. In that case, when one stream of information is going one way, how much is it getting distorted by myriad streams that are passing right through it from other directions?

Household electric quandry

silsurf — Wed, 18 Feb 2009 18:39:11 -0800

Odd electrical behavior in my bathroom? About two years ago I put a new light fixture in my bathroom. At the same time I also installed and inexpensive wall dimmer.

About a year ago I started experiencing very random, 10-30 second blackouts from the new fixture.

The blackouts are very graceful, almost as if they are being dimmed back and forth, they last 5-30 seconds and they happen a few times in the course of the evening (the only time the light is on and I noticed the behavior)

At first I figure it was a bad connection at the fixture, but no matter how hard I try to shake the fixture, even when the blackout is occurring, nothing changes. The fixture was not easy to put in, so the whole point of this ask is to figure out if there is anything to do before I take the fixture down.

Second I figured it was a bad dimmer, so I swapped that out. No change.

Now I do not know what to do, here is some other pertinent info:

Old house, original wiring
Incandescent fixture with two small "peanut" globes, the kind with two small stiff wires where it connects.
Both lamps dim when this occurs.

Any thoughts appreciated.

Henry

How to get a vacuum working again?

matkline — Wed, 14 Jan 2009 13:54:14 -0800

My dog chewed the power cable on my vacuum. Not realizing this, I turned it on and burnt a fuse. Is there any option other than replacing the vacuum? Would it be safe to wrap it with electrical tape?

Best CFL bulbs???????

boby — Sat, 20 Dec 2008 11:18:53 -0800

Which CFL bulbs are the longest lasting and cheapest to buy? I'm concerned about saving money on my electric bill but not worried about mercury content (if lights are broken). Are there any CFL bulb giveaways that are online?

Are self-installable dental electric nerve blocks on the horizon, at all?

Quarter Pincher — Thu, 13 Nov 2008 14:39:24 -0800

Would it be very plausible to hope that a consumer-good electric(al) nerve block be developed for dental/oral surgery pain management? Soon? I will likely be having lots of dental work in my future, unless I can somehow discover a drastically inexpensive way to skip right to dentures.

In the meantime and less pricey time, I'd ideally like a consumer-implementable electric(al) nerve block that I could install myself when needed, because getting the chem-shot is almost as bad as the toothache itself, so much that I've had my last umpteen fillings bored and filled without any shots and going purely off nitrous and goa-trance.

The pain-to-the-point-of-insanity I feel when injected with whatsit-caine nerve block meds into the gum is absurdly fearsome, but I'll overlikely be needing a number of root canals later in my years -- and it seems like an electric/electrical nerve block would be the answer, but to get a dentist to buy one and use it would take decades rather than me just bringing one in and using it myself.

Would you suppose the installation of electric(al) nerve block is too delicate or sensitive (pun, yes) of a procedure for standard consumers to implement, or could a rudimental version be contrived that essentially accomplishes the goal without needing to know advanced bio-science?