Forgive my electrical ignorance, but doesn’t “AC” mean “alternating current”? Does that mean that the hot and neutral wires are constantly reversing?
The “hot” wire is also known as the “line,” and it is indeed energized with 120 volts AC (in the USA). The neutral wire is “bonded” to the earth ground rod(s) at the incoming service panel (from the power company), so it should always have a voltage potential very close to earth (maybe 1 or 2 volts).
The AC thing is Alternating Current, so 120 times a second the voltage between hot and neutral wire changes from a positive swing to a negative swing. Since a full cycle is both a positive and negative swing, that’s 60 cycles per second, also known as Hertz or Hz.
All modern electrical appliances (and your RV) should have the incoming neutral wire isolated from the chassis. The chassis is connected (bonded) to the incoming ground wire in the power cord, officially known as the EGC (Equipment Grounding Conductor), and also known as the safety ground.
Getting the hot and neutral wires swapped in your extension cord is known as a reversed “polarity,” even though that’s a poor choice of words which causes much confusion. That’s because the AC voltage itself reverses polarity 120 times a second (see above).
However, the incoming wires are known as “poles” and an electrician’s definition of “polarity,” where the hot (black) and neutral (white) wires are reversed, is different from an engineer’s definition of “polarity,” where the voltage on those wires reverses itself 60 times a second from the AC current itself.
P.S. I’ve asked my friends at Southwire to come up with a decent prize for a contest this week, and they’ve supplied me with half a dozen of their really nice 3-meter kits. Read how you can win one of these great prizes.
And please be sure to read my message to Gary Bunzer, the RV Doctor: A promise between Gary the guitar guy and Mike the keyboard guy.
Mike Sokol is an electrical and professional sound expert with 50+ years in the industry. His excellent book RV Electrical Safety is available at Amazon.com. For more info on Mike’s qualifications as an electrical expert, click here.
Join Mike’s popular and informative Facebook group.
And you don’t want to miss Mike’s webcasts on his YouTube channel.
For information on how to support RVelectricity and No~Shock~Zone articles, seminars and videos, please click the I Like Mike Campaign.