Why does my polarity tester show “South” if MagnetRX uses North (Negative) polarity?
This is one of the most common sources of confusion when customers independently test the polarity of their MagnetRX products. An “S” reading on a conventional polarity tester does not necessarily mean your MagnetRX product was manufactured backwards. The key is understanding what the tester is designed to identify.
Most readily available magnetic polarity testers are designed for engineering and manufacturing applications, such as checking magnet orientation in motors, speakers, sensors, rotors, magnetic assemblies, and other industrial products. These instruments typically identify a magnet's north-seeking (N) and south-seeking (S) poles. MagnetRX uses the North (Negative) polarity designation traditionally used within magnetic therapy. Under the convention we use, the North (Negative) therapeutic face corresponds to what an engineering polarity tester may identify as the south-seeking (S) pole.
That's why you may place a conventional polarity tester against the body-facing side of your MagnetRX product and see an “S.” The tester may be functioning correctly, and your MagnetRX product can also be oriented exactly as intended. The apparent contradiction comes from two different polarity naming conventions being applied to the same magnetic face.
A helpful way to understand the distinction is with a compass. The north-seeking end of a compass points toward geographic North because opposite magnetic polarities attract. This relationship between geographic direction, magnetic polarity, and north-/south-seeking terminology is one reason the words “North” and “South” can become confusing without specifying the convention being used.