Went on a job this morning & my client had a note on the table to check an outlet that wasn't working next to her bed. This was a secondary request as I had other work to do in the house.
Anyhow, I didn't have time to look into it further, but here is what I found. Plug my Receptacle tester into it & its lights light up for correct wiring. Plug her lamp into it- nothing. Plug her fan in- nothing. Another outlet right next to it on a switch- plug in the stuff & they work. I changed out the receptacle with a new one- same thing.
Checked receptacle with my Fluke-119 volts hot to neutral-hot to ground.
Plug the light back in - Nothing. What the heck? Put my meter back on it- reads 119 volts. Leave the meter leads in & plug in the light- voltage goes to zero on meter -no light. Unplug the light- voltage goes back to 119v.Everytime I'd plug the light or fan in the voltage would go to zero.. Any Ideas for when I get back up there?????
You will not see the voltage drop on a loose neutral until a load is applied. And the plug in tester isn't enough. Had this exact same scenario maybe a year ago, sadly it took me for a spin, finally found the conductors were all burned up in the conduit under ground.
Thanks guys, I think everyone is on the right track- I'm thinking the same- it has to be a very delicate connection somewhere= and the load is breaking it......... I will follow up when I get back to it-
When having a loose neutral on a three phase system let's say for lighting circuits 1,3,5,n a b c phases. if the neutral becomes loose My Forman seems to think u can get 208 v or 480 ? is this true or do u just get excessive voltage?
If each leg is loaded the same, you probably will not notice anything. Till a switch gets shut off. Then, you will start getting weird voltages up to the transformer max. 208 or 480 depending on what the secondary is.
I've seen broken back stabs someplace do this. Connected just barely by a hair... good enough to read on a meter. Put any type of load on it, and the connection goes open and voltage goes to nuttin'.
The receptacle was not backstabbed & I also installed a new one. I never backstab as I learned the old way. I got a call from the homeowner last night and she tried the receptacle knowing that I had been there,
She said that she plugged her clock into it & it worked for about a minute then went off................. I will be looking at this before the week is out so I will report back to what I find.......
I didn't say that particular receptacle was backstabbed, only it may be backstabbed somewhere, or a loose connection.
I once had a faulty outlet the worked intermittently, I found out plugging something in a nearby outlet would make it work, pulled that outlet out and it had loose backstabes.
The receptacle was not backstabbed & I also installed a new one. I never backstab as I learned the old way. I got a call from the homeowner last night and she tried the receptacle knowing that I had been there,
She said that she plugged her clock into it & it worked for about a minute then went off................. I will be looking at this before the week is out so I will report back to what I find.......
Just check if the neutral is hot even with your cheater stick or meter if so then u got a loose neutral . I can almost guarantee that is your issue. Also if light flickers like a strobe effect then that's a good sign of a loose neutral .
I don't see that as phantom voltage. Suppose you have a 500 foot run of wire that is connected by telephone wire to a 120V source. Is that phantom voltage? It won't run a motor but the voltage is there---No???
I have seen underground cables that deteriorated until one strand was connected. Voltage read at the meter but nothing would run.
Even 500 feet of 12 wire your going to have the same problem this is a voltage drop issue. your conductor Size is not large enough (not enough resistance) to keep the voltage up for long distances
Even 500 feet of 12 wire your going to have the same problem this is a voltage drop issue. your conductor Size is not large enough (not enough resistance) to keep the voltage up for long distances
Even 500 feet of 12 wire your going to have the same problem this is a voltage drop issue. your conductor Size is not large enough (not enough resistance) to keep the voltage up for long distances
I'm with the one-strand-connection crowd on this one. I had a solid conductor break in the insulation and touch enough to light a meter to 116v, but not pass enough current to light a 60w lamp. Merely pushing the receptacle would break the connection. I finally saw the bent conductor on the third time pulling the receptacle out. Herp-derp = me.
According to the NEMA doc you linked earlier, the source is what defines "phantom" voltage, and they describe the source as capacitance as when conductors are in close parallel but not hard-connected. A failing conductor that is intermittently physically connected, or even discrete conductors that are shorting would not be "phantom" per this doc.
Thank you for that post. I wanted to state the same I knew BBQ used the term incorrectly as I understood it to be as you posted but I had no factual basis for my claim.
I see the difference this way - you can't get shocked from phantom voltage because there is no physical connection. Even one strand connected to a voltage source can shock and potentially kill you under the right circumstances.
I haven't tried it, but I think a low-impedance tester will still register voltage even with the one strand example.
I would bet a million dollars his receptacle problem is a loose neutral in the switch or receptacle... Stick ur wigy in the neutral slot of the receptacle if it blinks u got a loose neutral... Durrr
Ok then explain to me this. We had a full boat feeding sales floor lighting. A pipe came out of the bottom of the panel to a 4 s box then to an underground pipe to the other side of the store. the neutral was not connected in the 4 s box below the panel. All lights worked for a day or two . After the light control programers programed everything everything was ok came back the next day and lights were all off....how come lights did not burn out ? I have seen lots of loose neutrals never seen them ruin any lights? With out the neutral it has no positive and negative just a positive alternating to negative trying to return to source correct or wrong?
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