Basic electricity for dummy

[mscher]

Walmart has a plug with status lights, which plugs in an AC electrical outlet, telling of open grounds, reversed polarity and other abnormalities.<br /><br />One should be able to determine the same measurements with a DVM and thus, save the $3.79 and have yet one less toy to mis-place.<br /><br />Anyone have a DVM cheat sheet to accomplish this?<br /><br />Also, If you have two wire supply going to three wire, should the ground be connected to the common? Our farmhouse has some very interesting (and sometimes scary) wiring.<br /><br />Thanks

 

[crab bait]

Re: Basic electricity for dummy

spend the 3 bucs an save me from typin' for 20 minutes an still mite not convey..<br /><br />explain " if you have 2 wire supply going to 3 wire"..

 

[eurolarva]

Re: Basic electricity for dummy

Best way to remember wiring an outlet is black to brass. Or B to B. The white wire connects to the silver lug and the ground to green. If somewhere in the circuit the white and the black is reversed you can get a shock from it. As crab bait says get the adaptor. I dont know any simple way to tell if you have reversed polarity on AC using a DVM

 

[rc581]

Re: Basic electricity for dummy

marty. you cannot use a 3 wire recpt. meaning a recpt with a ground opening on it, on a 2 wire system. you can still buy the recpts. with no ground on it if you have the 2 wire system. it is illegal to use a grounded recpt. on an ungrounded circiut. if all else fails, you can use a g.f.c.i. recpt in its place. hope this helps you.....bob

 

[SlowlySinking]

Re: Basic electricity for dummy

marty, to check for reversed polarity check between the ground terminal and each slot, if the short slot has line voltage it's okay, if the long slot has line voltage you have a reverse polarity situation. If you get nothing from either slot you have an open ground or a dead circuit. To verify check between both slots, if you get line voltage the circuit is live, the neutral is good and the ground is open, if you get nothing the circuit is dead or the neutral is open. Of course the tester cannot tell if the neutral and ground wires are reversed, this takes a visual check, it's easier to use the circuit tester and get all 6 tests in one shot. For anyone trying this make sure your meter is set to AC volts and a scale that exceeds 120 volts.

 

[SlowlySinking]

Re: Basic electricity for dummy

So, what's inside the Circuit Tester, well to avoid taking it apart and ruining it I looked at the table of tests attached and it appears to be pretty simple. Please forgive me, I'm retired with too much free time. <br /><br />Look at a 3 wire wall socket and think of the 3 terminals as a triangle, to visualize this draw a triangle with the point down and label the left corner as NEUTRAL, the right corner as HOT, and the bottom corner as GROUND. <br /><br />In the circuit tester you have a indicator bulb connected across each of the 3 sides so draw some symbol across each side to indicate the light bulbs. <br /><br />The assumption is made that the circuit is live, correctly wired at the source and all three <br />wires are connected (right or wrong) one each to the brass, silver, and green screws in the <br />wall outlet. Remember, a bulb will only light if one end is connected to HOT and the other end to NEUTRAL or GROUND. <br /><br />Here's what happens;<br /><br />If the bulbs between HOT & NEUTRAL and between HOT & GROUND light you're done, it's wired <br />correctly. <br /><br />If all bulbs are dark the HOT is open or the circuit is dead because no matter how you mis-<br />wire it one or two bulbs will light up. <br /><br />If only the bulb between HOT and NEUTRAL lights you have an open ground, <br /><br />If only the bulb between HOT and GROUND lights you have an open NEUTRAL, <br /><br />If the bulbs between NEUTRAL and GROUND and between HOT and GROUND light you have the HOT & <br />GROUND reversed, <br /><br />If the bulbs between HOT & NEUTRAL and between NEUTRAL & GROUND light you have the HOT & <br />NEUTRAL reversed.<br /><br />If you see all the bulbs light you've probably entered The Twilight Zone.

 

[CalicoKid]

Re: Basic electricity for dummy

The ONLY place your ground and neutral should be connected is at the main service diconnect (at the main panel or meter enclosure). Any other bonding is illegal and potentially dangerous. Farm wiring is unfortunately often a nightmare.<br /><br />If you need a grounded type receptacle on a two wire ungrounded circuit it is acceptable to replace the receptacle with a GFCI receptacle without connecting the ground terminal. You need to label the outlet 'no equipment ground'.<br /><br />Get the plug tester and check all your outlets for piece of mind.<br /><br />...acceptable receptacle ...

 

[TwoBallScrewBall]

Re: Basic electricity for dummy

This is good info. The house we bought a year ago is early 1900's vintage, and when built only had gas lines throughout the house for lighting. No electricity in the area. Somewhere along the line the gas lines were capped off (still all there, pressurized, just capped) and electric was installed. All 2-prong outlets, some outlets piggybacked off other outlets using extention outlets that plug into an existing outlet and have a surface mount outlet on the other side of the wire. I understand scary electrical, believe me. Hopefully this winter we will be beginning a big renovation project in which I will be going room by room and:<br /><br />1) Completely stripping the room walls and ceiling down to studs (currently very old plaster covered in very old wallpaper).<br /><br />2) While everything is open, run new 3-prong outlets, wired correctly<br /><br />3) Install flush mount ceiling lighting / ceiling fan boxes<br /><br />4) Resurface walls and ceilings with drywall, spackle, new moldings, paint, move on to next room. <br /><br />Going to be a lot of work but I'll be doing it myself so will only be paying for materials. <br /><br />As it is right now, I went to install a ceiling fan upstairs, and found when looking for the breaker that my kitchen lighting, dining room lighting, and all upstairs power (3 bedrooms and a bathroom) are all on one 15A breaker. Somehow we've never tripped it.....

 

[mscher]

Re: Basic electricity for dummy

Sorry for the delay Crab, I have to use a library Internet connection.<br /><br />"this old house" has two wire everywhere and the pole light (which the barn juice is tapped into), has the fat black wire and uninsulated stranded (support)cable overhead.<br /><br />Some of the home wiring has been updated to 3 wire, but the ground is usually hanging or connected to the common.<br /><br />Without completely rewiring the house, I would like to at least make the grounds work and make sure the hot and common are where they should be.<br /><br />Marty

 

[crab bait]

Re: Basic electricity for dummy

you CAN NOT by right or by code by hook or by crook install a 3 wire recepticale to a 2 wire system... it's wrong an gives the security of a grounded outlet was infact it's a cruel an deadly hoax.. <br /><br />HEED THIS WARNING...