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Discussion Starter #1
We are working at a 3 story house that was built in 1895. There is one recepticel on the second floor that will not run a drill but plug a light into it and the light seems fine. There is 120 volts and I changed the recepticel to a new one. There is a recepticel on the 3 rd floor on that is on the same circuit and is fine. The wire runs from the 3 rd floor down to the recepticel on the second floor then continues to the first floor where there is a ceiling light. The light on the first floor seems fine. The wiring for this circuit is probably 30 years old. I've remade the wire nut connections and still can't figure out whats going on. The drill would barely turn like the voltage was low. Any ideas? Thanks!!
 

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Either the connections at the receptacle are still no good or there is a problem at the light below, or elsewhere.
You say the third floor receptacle is fine? Meaning it can run the drill? This would be strange, especially if the second feeds the third as you suspect.
Are you sure there is nothing else on the circuit? There may be a bad splice somewhere you aren't seeing.
A bad splice can show full voltage until a load is applied. This can also be very dangerous if the splice is not in a box as it should be. I have seen plastic wire nuts melt away from a bad splice underneath.
 

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Discussion Starter #5
I am pretty sure that the 3rd floor feeds the second then the first. There may be more on that circuit but I have not gone that far yet. I'm going to see if I can get an amp meter and see how much of a draw I'm getting. But for now it doesn't make much sense to me. Its possible that there might be a wire almost broke in half as mention. I fixed one recepticale already where the wire broke completely. I might have to remove the recepticale and put a blank cover on. I guess it makes sense that a small current load will work but a bigger load won't. But why wouldn't the partial wire thats remaining burn through? No the drill is fine.
 

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Low Voltage problem

First things first. Measure with the voltage on the drill with your DMM. You say is low but how low?. If is 70 Volts then you got 50 volts missing. Meausure the voltage on the outlet with no drill. How low is it? Light bulgs work with low voltage too. If you got less then 120Vac I will ohm all the wiring from the 1st floor to the 3rd floor and see where you got an open. It sounds to me like you are missing a ground somewhere but that is just me hope that helps you. Keep up the good work. Viva Texas.
 

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just from the info you have given my guess is there is a nuetral lost somewhere in the circuit .an inductive load such as a light will work with a lost nuetral but not a full brilliance usually going thru another circuit where it is shared .but put a motor load such as a drill or a fan at that point and there is no true return path and it wont work.

the only way to find it is to start taking apart devices and splices till the problem is found just a guess but i would start at the fan on second floor but it could be anywhere.
 

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boogie said:
just from the info you have given my guess is there is a nuetral lost somewhere in the circuit .an inductive load such as a light will work with a lost nuetral but not a full brilliance usually going thru another circuit where it is shared .but put a motor load such as a drill or a fan at that point and there is no true return path and it wont work.

the only way to find it is to start taking apart devices and splices till the problem is found just a guess but i would start at the fan on second floor but it could be anywhere.
I don't mean to be persnickity, but incandescent lights are not inductive loads yet the drill motor is. I'm curious how a light can work without a neutral, on multiwire circuits a lost neutral creates a 240 volt condition.
 

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im glad someone was checking up on me sorry for the misinformation i ment incandescent load it had been a long day.and yes a multi wire circuit will give 240 v when a nuetral is lost ,but on most older houses there are very few multi wire circuits , just 2 wire circuits ran all over the place and taps everywhere .

a lost nuetral on one circuit can get a return path on another circuits hot conductor tied into at some point (and on the same phase )usually thru a light fixture (incandescent lamp) or when an appliance is pluged into an outlet .

again sorry for the flub up on words ,need to check my posts before hitting the reply

the problem could be anywhere and being an older house can make it even harder to find.
 

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Discussion Starter #10
I noticed that this thread was responded to again. I have been working on other parts of the house so I have not been able to dive into the problem further. But elsewhere in the house I have found the hot and neutrul reversed. (The white wires were hot instead of the blacks) The circuit is feed from a subpanel on the third floor. The 2 outlets and the light are all on the same south wall and pretty much vertical to each other. But I think I will unhook the light and see what happens.
 

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boogie said:
a lost nuetral on one circuit can get a return path on another circuits hot conductor tied into at some point (and on the same phase )usually thru a light fixture (incandescent lamp) or when an appliance is pluged into an outlet .
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What you say is both electrically correct and extremely interesting. I've never encountered this but will file it away in my brain, it may come in handy some day.

Whoop! Whoop! :cool:
 

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this may be a little off the current subject , but one of the stranges one i found was a homeowner called me in complaining that the old pullchain light in the laundry room stopped working but would work when the washing machine ran but was real dim. come to find out someone had wired the light but didnt have a neutral and used the old cast iron drain pipe as the neutral with a peice of plumbers strap.
while very unsafe it worked untill they had problems with their drains and a plumber had replaced a bunch of drain pipe with pvc,thus the only time it would work was when water was flowing . just goes to show you in old houses you can run into some crazy sh*t
 
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