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Discussion Starter · #1 ·
I just changed out two old outlets. After I changed the outlet, I tested the current. The first outlet produces 123 volts, however the 2nd outlet (which is also the last outlet on the circuit) only produces only 117 volts. These outlets are only 5 feet apart. What happened? Please help.
 

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Turn the breaker off first, pull both outlets out and check the all the connections on both. One of the wires is probably loose.
 

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Discussion Starter · #3 ·
Turn the breaker off first, pull both outlets out and check the all the connections on both. One of the wires is probably loose.
I double and tripled checked it. I actually redid my whole connection and even changed the outlet again. Does that mean the wire is probably broken somewhere in the wall? What will happen if I run it my stuff at 117 volts?
 

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Nothing. You have to consider voltage drop, and with this being Summer, it is not surprising to see flucuations in volt's.
 

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Discussion Starter · #6 ·
How important is your voltage level for your usage? Is it A/V equipment? You could try a power conditioner?

It's outlet is not important at all. Actually, it is barely ever used. It's just strange that all the outlets in my house test at around the same voltage with the exception of this one.
 

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It's outlet is not important at all. Actually, it is barely ever used. It's just strange that all the outlets in my house test at around the same voltage with the exception of this one.
Voltage drop is dependant on load. If you say the outlet less than 5 feet away is reading 123V and it is 117V with no load on the 117V outlet. There is something wrong there. If all you're connections are good, I'd try to fish in a new cable.
 

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I agree with Charlie. Something is wrong. There's no reason to drop 5-6 volts in 5 feet.
 

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There is something wrong, that type of voltage drop in 5 feet with no load is something that neeeds to be corrected.
 

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I just changed out two old outlets. After I changed the outlet, I tested the current. The first outlet produces 123 volts, however the 2nd outlet (which is also the last outlet on the circuit) only produces only 117 volts. These outlets are only 5 feet apart. What happened? Please help.
Are these two outlets physically 5' apart or electrically 5' apart (5' of wire)? Are you 100% sure there isn't another load somewhere between these two outlets?
 

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Discussion Starter · #11 ·
Are these two outlets physically 5' apart or electrically 5' apart (5' of wire)? Are you 100% sure there isn't another load somewhere between these two outlets?
I'm 100% sure these are 5' apart by wires. I can actually see the wires that connect these 2 outlets together. Also, I'm 100% sure there is not another load on these outlets. I know because when I turned off the circuit breaker, only 2 outlets turned off.

Does that mean it is dangerous to use? It would be nice to use these outlets occasionally. However, if it is dangerous, I will just turn it off from the breaker since it's so seldom used that it's not worth repairing.

Thanks a million.
 

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If you can follow the wire like you say and both receptacle have been replaced, but you are seeing a 6 volt difference with no load, something is wrong somewhere.
Try this for fun. I assume you have a toaster or a toaster over.
1) Plug it into the bottom of the first receptacle and measure the voltage on the top one with the toaster on.
2) Next, move the toaster to the second receptacle and do the same thing.
3) Next, leave the toaster plugged into the second receptacle but measure the voltage at the first receptacle while the toaster is on.
 

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What are you measuring the voltage with? and have you tried mearsuring any other outlets in the house? are any of the other outlets measuring 117 volts?
 

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If the outlets are only 5' apart, measure the resistance of the wire with an ohmeter on its lowest scale.
The resistance, white to white should be exactly the same as the black to black resistance.
If there is any difference its likely to be a cracked conductor.
I would expect both conductors to be close to zero resistance.
 

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There is clearly more resistance there than usual,
Check for loose connections first,
The contacts in the receptical could be dirty.
Then check the cables,
could be broken or stretched and damaged,
might have to replace them.
What were you testing the voltage with ?
Did you have a load on the line ?
 

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Did you any chance try read the voltage with diffrent voltmeter some case they can be very senstive and may cause reading stray voltage or something can affect the reading.

Some case the best answer is run the ohmmeter and read the ohms on the conductor between the two spots as someone mention above and I have a feeling there may be a nick on the conductor or nail or something hit it.

Few case I do find them a flying illegal spices so end up fix it properly.

Merci,
Marc
 
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Are you sure you are comparing apples to apples?

Measuring X volts at outlet A with no load anywhere in the house and measuring Y volts at outlet B with some load anywhere in the house is comparing apples to oranges.

The chances of accurate readings are greatly improved if you measure each location twice alternately, that is, outlet A then outlet B then outlet A again then outlet B again. Are both the outlet A readings identical and both of the outlet B readings identical?

Jiggle the test probes to make sure you are getting a good contact.
 

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Discussion Starter · #18 ·
If the outlets are only 5' apart, measure the resistance of the wire with an ohmeter on its lowest scale.
The resistance, white to white should be exactly the same as the black to black resistance.
If there is any difference its likely to be a cracked conductor.
I would expect both conductors to be close to zero resistance.
I have a Craftsman Professional multimeter and never even knew what the ohmeter was for. I watched a few videos on youtube and finally figured it out. While testing, I was moving the wire with my hand. I noticed that the ohms would change if the wire was moved. So I pulled more of the wire out of the wall and it was broken. The insulation was holding it together.

Thanks,
 

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A reminder to those folks eavesdropping. Turn off power before using an ohmmeter or continuity meter or the ohms function of a multimeter.

Also if you are testing a wire, remove that wire from any screw or hole it was connected to before testing. If you are testing at a screw terminal, remove all wires from the screw before testing. This will reduce the chance there is an alternate route for a tiny current emitted by the ohmmeter and such an alternate route will mess up the reading. (You only need to do this for one of the two meter probes.)
 
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