Only 84 volts on a circuit that was fine yesterday.
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Sounds like you may be using a digital volt meter and it's reading a ghost voltage like when a disconnected wire is running in a cable next to a live wire and picking that ghost voltage up. You may have unknowingly cut the line conductor for that receptacle.
Check at the panel to see if that circuit is part of a multi wire cable (black-red-white-green wires in the same cable). Can you be sure it worked before? Is it possible that it's a switched receptacle and the switch is off? Check and advise.
Check at the panel to see if that circuit is part of a multi wire cable (black-red-white-green wires in the same cable). Can you be sure it worked before? Is it possible that it's a switched receptacle and the switch is off? Check and advise.
Both of the receptacles were in use recently, and yes I used a digital volt meter.
I'll have to check the panel to look at the wires on that circuit but I'm pretty sure its just black white ground.
This is a kitchen circuit and I don't think any of the receptacles are switched.
I'll have to check the panel to look at the wires on that circuit but I'm pretty sure its just black white ground.
This is a kitchen circuit and I don't think any of the receptacles are switched.
I checked the receptacle that we worked near, it had the wires pushed into the back, I snipped them off and wired a new receptacle to the side terminals, no change.
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OK just something some overlook. Let us know what you find.:wink2:
Next time twist them out unless you have a gross abundance of wire length. You must have 6" beyond the end of the cable sheath, and you don't want to get near that limit. Twisting them out has a side-benefit; you get to inspect them for arcing and pitting, which reasonably proves where the problem was 
Also generally there's no reason to scrap out a backstab recep if it has workable side screws, unless you just want the better quality of the $3 jobs
Also generally there's no reason to scrap out a backstab recep if it has workable side screws, unless you just want the better quality of the $3 jobs
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That's a good thing since you're leaving it better than you found it! That would have caused trouble eventually anyway.
Thanks for the update/feedback.
Thanks for the update/feedback.
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Why does everyone in internet chat groups get the words lose, and loose messed up? :vs_mad:
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Yeah, what a bunch of loosers. :devil3:
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Yeah, I guess we do loose a lot around here. :biggrin2:
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Honest question...Remember I'm a GC not an electrician....
But, if the circuit is not under load, why does a pour connection (that's a joke)
affect the voltage read on a low impedance MM.
Can a pour :wink2: connection create that much resistance.
TIA
(I guess that I like to fully understand an issue, regardless of whether it is now working...:smile
But, if the circuit is not under load, why does a pour connection (that's a joke)
affect the voltage read on a low impedance MM.
Can a pour :wink2: connection create that much resistance.
TIA
(I guess that I like to fully understand an issue, regardless of whether it is now working...:smile
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That's a good question... and I have met a lot of GC's that wouldn't know the answer but some, maybe most, wouldn't care either. I give you one up for that.Honest question...Remember I'm a GC not an electrician....
But, if the circuit is not under load, why does a pour connection (that's a joke)
affect the voltage read on a low impedance MM.
Can a pour :wink2: connection create that much resistance.
TIA
(I guess that I like to fully understand an issue, regardless of whether it is now working...:smile
The only way a voltage drop occurrs on a circuit is when a current is flowing. Ohms law backs that up. For current to flow, there must be a resistance across conductors of different voltage potential. A poor connection in series with such a circuit will drop part of the original voltage across the poor connection and the remainder across the device used for measuring it (or any other resistance in parallel).
For example, if the measuring device had no resistance at all, then the circuit could have an extremely poor connection and still measure full voltage. That is never quite the case... even the digital voltmeters have an input resistance, albeit quite high. They are often referred to as "high Z" or "high impedance" meters. Some of the more expensive ones have a "low Z" setting to use when in doubt about the possibility of being fooled with ghost reading when measuring a high impedance circuit (one with a high resistance connection for example). That's where the strange voltage reading come into play. That's why on crude electrical work, a digital voltmeter isn't often the best way to get a useful reading.
An analog meter with lower input resistance will give more useful reading for common circuits that most electricians will encounter. A cheap analog meter is one choice. The trusty "Wiggy", which is an electrical solenoid type volt measurement device with a built in growler is a good choice for carrying in the pouch. It's bullet proof and has a scale the shows all the voltages you will ordinarily come across. It loads the circuit even more than the analog meter.
The lower the input resistance of the measuring device, the more the voltage will drop across the poor connection in the circuit. Ohms law at work as always.
Now as to a pour connection, that sounds like someone you may know who works at a winery. :biggrin2:
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Moreover:
Most cheap analog voltmeters have a sensitivity rating of 2,000 ohms per volt. That means if you set the selector switch for the 125 volt scale, the meter input resistance will be 250,000 ohms (125 X 2,000). A high end analog meter will have 20,000 ohms per volt sensitivity (like the 260 Simpson), but still much lower than a digital meter. Most digital meters will have an input impedance of several megohms.
And don't let my use of the terms resistance and impedance like they were the same thing confuse you. While it may be OK to take that liberty when referring to voltmeters, in an electrical circuit, they are to be considered quite differently.
Impedance referrs to the the equivalent resistance imposed on an alternating current circuit by its the combination of its frequency, inductance, capacitance and resistance.
Resistance alone referrs to a direct current circuit characteristic and means the total resistance to current flow, no other factors are relevant.
Most cheap analog voltmeters have a sensitivity rating of 2,000 ohms per volt. That means if you set the selector switch for the 125 volt scale, the meter input resistance will be 250,000 ohms (125 X 2,000). A high end analog meter will have 20,000 ohms per volt sensitivity (like the 260 Simpson), but still much lower than a digital meter. Most digital meters will have an input impedance of several megohms.
And don't let my use of the terms resistance and impedance like they were the same thing confuse you. While it may be OK to take that liberty when referring to voltmeters, in an electrical circuit, they are to be considered quite differently.
Impedance referrs to the the equivalent resistance imposed on an alternating current circuit by its the combination of its frequency, inductance, capacitance and resistance.
Resistance alone referrs to a direct current circuit characteristic and means the total resistance to current flow, no other factors are relevant.
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Surf..... AGREE and thanks........
(I could not understand your answer to my question and then I went back and read my question parameters....I typed low impedance for the meter, when I meant high resistance/impedence. like most MMs, (and no other load on the circuit except normal wire resistance and a poor connection.))
Maybe, no not maybe, I had a couple of pours tonight.:smile:
To me, given a high impedance MM, and no load on the circuit, seemed a 35V drop was a lot of drop for just a loose connection. Do you think so.????
Couple that with the fact that the circuit had been fine before, and the OP did OTHER wiring in the circuiut, and had not touched that box/connection he said was loose, ........it made me wonder if perhaps he had lost a neutral somewhere else and got two legs in series and was measuring with a load on.
It just seemed like 35V was a lot of drop for a poor connection read with a high impedience MM. Maybe not....Again I'm a GC with more than a couple of pours tomoght.:wink2::smile::smile::smile:
Best...I'm probably still mixed up.
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Look at it this way... if the poor connection had 2 megohm of resistance and the digital meter had 2 megohms input impedance, there would be 60 volts dropped across the poor connection and 60 volts measured by the digital meter.
Since there was 85 volts measured by the meter, there was only 35 volts being dropped across the poor connection. That voltage ratio can be used to determine the resistance of the poor connection since we know the input impedance of the meter (actually we are just faking it for this example). The poor resistance would be somewhere near 800,000 ohms, if we assume the 2 meg meter input impedance. That means the wires were barely connected and likely through some oxidized copper with very small surface contact area.
I find the scenario a little hard to believe... same as you do. Judge Judy says when things don't sound right, they usually aren't true. We may not have heard the last of that poor connection.
Since there was 85 volts measured by the meter, there was only 35 volts being dropped across the poor connection. That voltage ratio can be used to determine the resistance of the poor connection since we know the input impedance of the meter (actually we are just faking it for this example). The poor resistance would be somewhere near 800,000 ohms, if we assume the 2 meg meter input impedance. That means the wires were barely connected and likely through some oxidized copper with very small surface contact area.
I find the scenario a little hard to believe... same as you do. Judge Judy says when things don't sound right, they usually aren't true. We may not have heard the last of that poor connection.
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