Check your house wiring!

[Toaster]

Hello folks,
I'm staying in Phoenix, AZ for a bit doing some freelance PC/networking work.
I found some very disturbing problems with existing house wiring of homes built in the mid 50's to mid 60's.
Aside from the fact that few have grounded outlets, many outlets were wired incorrectly. In this, the "neutral" and "hot" wires were REVERSED and this wasn't consistant. Often, the outlet was wired reversed or correct in the same household. First thing on folks mind is the outlets were previously replaced and in some situations this was true, BUT NOT ALWAYS. As a matter of fact, an average of 2 outlets per households were inconsistant. Existing grounds did not exist in most cases and in some were not connected.
So....dash out and grab an outlet checker.
These are available at Radio Shack and "Home Centers" and could easily save a life and connected equipment.
In one particular case, 2 outlets in the same room had differing wiring. The home owner added an earth ground to these outlets. Now on one outlet, the "hot" and "Neutral" are reversed and one outlet is correct. A VERY dangerous situation. I arrived at this residence and the homeowner showed me the replaced recepticals with short wire pigtails still attached. He left these pigtails attached to help him to reconnect the wiring in the way the original was wiried.
He damaged a computer, TV, AV equipment and other gear and got a big shock to boot when he connected his CATV cable which provided his own ground.
So....NEVER assume the house is wired correctly, check all outlets.
Never use "ungrounding" adaptors to use devices with a groung prong.
Incorrect wiring is both a shock and fire hazzard as well as a hazzard to connected devices.
Check'em folks....!!!!!!!

[reboot]

I'm not sure if I should respond to this. You definitely don't want to live in my house.
About half the plugs are 2 prong only, some so old they're not even polarized.
The other half are 3 prong, but only 2 wire...so much for grounding...
The Oven, Stove, Fridge, and Dryer are all on the same master circuit, with the Stove and Fridge dropped to 110v. Any 3 devices on at the same time, and it's popped.
Major living room circuit (TV, VCR, etc.) is wired with master bedroom (opposite end of the house) but on the same circuit. Guess what happens when two TV's are turned on at the same time?
Upstairs lights/plugs are wired in the same circuit as the furnace and A/C.
Needless to say, it would never pass an inspection, and I've had to go through the labour intensive process of running new wire through the walls, just to get a stable circuit for the PC. Added a second PC, rewire another socket. Added the 3rd PC, more wiring.
Eventually it'll all get done, but even now, I can hear the fan on the CPU speeding up and slowing down with fluctuations in power, and that's with a 450w supply.
At least I can deduct my parts and (some) labor from the rent.

[Alienware_Dude]

I use a simple receptacle tester on any outlet I use, both for a PC or for ESD earth ground. Also, my Dad rewired/replaced all the old outlets that were in this house back in the late 80's, so I know they are all correct.

[Toaster]

Howdy again folks,
Reboot, I hear ya. Those older homes can be a real nightmare.
I was surprised here however with a number of building practices not including the wiring.
In the aforementioned case, the homeowner IS the original homeowner and knows of no prior electrical work.
Also, all the replaced outlets are the same design and age. Each of the replaced outlets had "pigtails" left attached by the home owner to aid reconnection. Even the outlets were marked "black" and "white" . Even with this visual aide, the "builder" incorrectly connected the wiring. Iv'e now seen this on 8 differing occaisions out of 15 jobs. In this situation, the homeowner had the miswired outlets in the same room (living room). When the outlets were used, the damage was immediate and the shock risk present. The connecting of the CATV cable produced an immediate "flash" and blown breakers. I also feel the CATV operator failed to make proper inspections prior to connection which could have alerted the homeowner to a VERY dangerous situation.
Keep alert, keep alive!

[Floppyman]

Hi Toaster,

How are ya? Thanks for the excellent information, I'll bookmark this for reference. Do you think this might be something to be aware of at college dorms as well? Thanks.

[Force Flow]

Oooboy. I never thought of college dorms. Yeah, some colleges are old and they haven't upgraded the wiring. That's a good thing to keep in mind. I think that most technology colleges are up to date, though (MIT, RIT, RPI, etc.).

[Tuf]

Good to see ya back Toaster!

[suitcase]

I had my home built and moved in in '73. At that time there was no code that required the builder to use two wire with ground romex. The only wiring that is has ground is the #10 that supplied my base board elec. heat. I've since removed all the elec. heat and whenever I could upgraded to 2wire/w ground. My pc is on a separate outlet with it's own breaker.

Oh, and I just thought of this. I requested the builder place 230w recepticle below the window in my dining room in case I wanted to install a room AC in the window. Well, they put a 120w standard recep. there and I assumed that they had forgotten my request. First time I used it was to plug in a small TV and POP it was gone. Being rather electrically challanged I plugged in my 1/4in drill motor and it ran way too fast. I knew then they had actually put a 120 outlet on a 230amp double pole breaker. I know now that wasn't a very safe way to test the voltage, but I didn't know any better back then.

[Toaster]

Howdy folks,
I suggest that folks NOT ASSUME ANYTHING and check outlets firsthand and on an individual basis.
Building practices vary by locale and so would methods.
In your case Flopster, I would check just for the sake of doing so.
The outlet checkers available are about 3-5 bucks or even less and are about 90% accurate.
Where their accuracy may falter might be the "integrety" of each line. This being say a connected but "resistive" ground. The trio of LEDs often used simply illuminate to note if a connection exists and polarities, not the integrity of those connections. Still, this simple tool can save lives and heartache.
I make it a habit that BEFORE I connect a grounded appliance, I check the associated outlet(s).
Be especially wary when multiple appliances are connected to differing outlets that still share common connections, such as AV gear.

Assume nothing and you should be better off.

[HAL9000]

Cool info Toasty... I'm out to buy one today and check things out. I live in a townhouse that were built in the 50's, so who knows what's right or wrong with the wiring.

[mattg2k4]

One of my friends lives in a house that doesnt have grounded outlets. He was wondering if he could wire neutral and ground on the outlet to the neutral wire. It seems to me like neutral and ground are the same thing, and that would theoretically give him grounded outlets. But I'm not sure it would be the same, otherwise they wouldn't bother putting a third prong in outlets. Would his idea work?

[Toaster]

Howdy Matt,
Absolutely NOT!
A/C house wiring uses a Neutral, Hot and ground. (assuming standard US)
What your friend suggests could not only pose a shock hazzard but also a hazzard to connected appliances.
The ground is an "earth ground" where ideally a brass/copper grounding rod of 3 feet is driven into the "earth" where all grounds connect. Another suitable ground is a cold water pipe . (assume a metallic water pipe)
In no case should you do as your friend suggests.

[mattg2k4]

Thats what I figured, but it was worth finding out. Thanks.

[Tuf]

Where I live it is very common to see the common grounded to the breaker box and the breaker box grounded to an earth ground. Then they just pull two wires to the outlets through metal conduit and install metal switch/outlet boxes. They then hook up a three prong outlet with the two wires like normal but they add a third short wire connecting the ground and the common to the box.

I don't like it and I wouldn't think it would pass any current codes. It does work, but it is potentially dangerous. They are relying or hoping that the conduit maintains a good ground path back to the box. It would be much smarter to run a ground wire back and is generally not too difficult since there is conduit along the whole path.