I ordered a simple voltage monitor for testing power supply at campgrounds. Reads voltage, and if there is correct polarity, or open ground.My parents own part of a small lake, that they've made into a sort of private campground. They have electricity run there, with 3 different 30amp connections. Today I brought my TT there to have it ready for our annual 4th of July celebrations and decided to use my voltage monitor. Voltage was fine 120 volts reading, but it read reversed polarity on all 3 hookups. The lone 20 amp standard outlet read correct polarity. We've had several RV'S connected there for 2 years. Never had an issue at all. My parents RV is there most the summer. My question is what sort of issues can reversed polarity cause? I'm hoping my voltage monitor isncorrect, because today we switched the hot and neutral wires on all the hookups so they now read correct polarity.

Seldom is it ever an issue but it was good to correct before you did have a problem. In my view it is more for safety. A lot of battery back up for computers will test for this and people did not even know about the wiring issue.

Can be dangerous in the event of a failure in something like the water heater or fridge. Also I don't think the GFCI's will function correctly.I would open them up and swap the connections on the back of the outlets. It's easy and there's no sense in keeping it wrong.

Reverse polarity on AC power means that the Hot & Neutral have been switched.Turn off an AC circuit breaker and you interrupt the hot side.........but if reversed the neutral is hot and would still be energized. Not good from maintenance safety point. Fix it before somebody gets electrocuted working on a hot circuit

Thanks for the input. As noted in my original post, we corrected the issue already. Glad that my voltage monitor came in handy the very first time I used it.

how can you have reversed polarity in a AC circuit? it reverses every 60 milliseconds.You can have out of phase. where one of the hot legs is attached to a ground. That usually shows up quickly and for a short time. :)

Reversed Polarity Issues? | Good Sam Community

wa8yxm
Explorer III
Jun 29, 2014
I will give you 3 scenarios

1: You are plugged in to an outlet with a DOUBLE INSULATED power tool and there is a neutral to case short.. Normal or reverse polarity, NOTHING bad happens. since its double insulated. YOu are safe

2: Tool is not double insulated, and some idiot broke off the 3rd pin.. Been nice knowing you.. Depending on several things you could easily be dead if it's reverse.. Normal no damage.

3: HOT wire to case, as in 2,, but normal polarity, Same as 2.

HOT wire to case, 3-rd pin present and propely grounded, CLICK of darkness (Breaker trips) you are safe.

GFCI, may not work if reverse connected and thus may not protect you.

TRUE STORY:
Bought a trailer, 20 amp twist lock, inlet,, Prior owner made his own adapter,, Well he reversed both it and the extension cord he made it from (He cut the plug end off an extension cord and put a new plug on what's left and the twist lock socket on the pig-tail)

Plugged in with his cord, Rverse-Reverse = normal so it worked fine

Plugged in with MY 12ga 100'er.. Liked to knock me on my ... er... pride.

Things that should have been at ground were, in fact, 120 volt.. But the safety ground meant some things were at ground.. Like the metal sink.

Finally I fixed the adapter.. Then I used HIS cord and .. Fixed it.
Gene_Ginny
Explorer
Jun 30, 2014
Old-Biscuit wrote:
Reverse polarity on AC power means that the Hot & Neutral have been switched.

Turn off an AC circuit breaker and you interrupt the hot side.........but if reversed the neutral is hot and would still be energized. Not good from maintenance safety point.

Fix it before somebody gets electrocuted working on a hot circuit
Well said, simply stated, and to the point ... alas, not everyone reads.

Tom/Barb wrote:
how can you have reversed polarity in a AC circuit? it reverses every 60 milliseconds....
Bobbo
Explorer II
Jun 30, 2014
Tom/Barb wrote:
how can you have reversed polarity in a AC circuit? it reverses every 60 milliseconds....

Wiring without reversed polarity, GROUND and NEUTRAL have 0v between them.

Wiring with reversed polarity, GROUND and NEUTRAL have 120v between them.

Don't even consider reversed polarity bootleg ground!

Forum Discussion

Reversed Polarity Issues?

About Technical Issues

Related Content

Reverse polarity

Wireless Reverse Camera Questions

Reverse lighting question

Blowing Fuse When In Reverse

COUGAR, POLAR PACKAGE -COROPLAST UNDER BELLY