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I recently bought an older house and on one of the circuits every outlet (7 outlets spread out over two rooms) gives a "hot/neutral reverse" reading when I use a circuit tester. I looked at each outlet and each one has the correct wiring colors (black to brass, white to silver, and copper to green). Then I measured the voltages using a DMM, and I get the following results (on every outlet): hot to neutral: 120V, hot to ground: 0V (!) and neutral to ground: 120V (!). Then lastly I used a non-contact voltage reader and on every outlet it lights up on BOTH the ground and the hot wires, but not on the neutral wires. Why would the ground wires be live?

Update: thanks for all your responses so far. I used a circuit analyzer and found some more details 1) analyzer also says it's a hot neutral reverse 2) ground to neutral shows 33.5 volts rms 3) ground to hot shows 121V RMS 4) ELL (estimated line load) is weirdly high, 20 amps when there's nothing plugged into any of the outlets (no fans or anything similar on the circuit either). 5) voltage drop is higher than it should be, highest reading was 11% drop for 20 amps 6) impedance is high too, hot reading impedance was 0.67 ohms.

I scheduled an appointment with a professional electrician since the knowledge from my college circuits course and some googling is feeling tapped out. I'll update this post with whatever the pro finds.

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    How is the cable terminated in the panel? Does the circuit actually work and power things? – Harper - Reinstate Monica Oct 5 at 20:04
  • Can you post photos of the inside of the panel? – ThreePhaseEel Oct 5 at 20:31
  • @Harper, yes the circuit works fine and powers things. I haven't checked the panel yet but I'll go take a look and follow up with a picture. – picardhasyourback Oct 5 at 20:53
  • Are there other outlets in these rooms? The reverse could be in a daisy-chained outlet that you didn't inspect. – Mattman944 Oct 5 at 20:57
  • @Mattman944 that's what I was hoping for, but I looked at every outlet and each one had the correct colors. – picardhasyourback Oct 5 at 21:07
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Find the breaker for those outlets and check that the neutral live and ground are correctly connected in the panel.

Then find every other device on that breaker and check the wiring there.

the bad connection could be behind a light switch or in a ceiling box.

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I was also thinking you were checking outlets downstream from one that was incorrectly wired, just as @Mattman944 had suggested.

I would definitely try to identify where the power is coming into the room from the panel i.e. the "home run" and ensure the hot is coming off the appropriate breaker (size & type for the room) and the neutral is tied to ground bar (if this if the main panel), and all those colors are in fact correct.

How old of a house are we talking? Is this all copper Romex, or old 2-conductor knob&tube?

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First lets ignore the non-contact voltage readings. The most common reason for reading "hot to neutral: 120V, hot to ground: 0V (!) and neutral to ground: 120V". Would be a broken ground, and since you live in an older dwelling this may be an addition or repair and whom ever installed it has not run the ground back to the panel. Your neutral to ground reading is probably a reference voltage being read through a remote piece of equipment like a motor. Or more plainly a difference of potential between the neutral connected to the panel bus and the ground which is not.

As everyone else has already stated. Check the polarity all the way back to the panel and run through the circuit to see if you can find the broken ground.

I have in my lifetime, seen houses wired with the white conductor attached to the breaker and the black connected to the neutral bus. Rare but not impossible.

Good luck

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