How to Determine Magnetic Polarity with Mag-Probe

***NOTE This video incorrectly states that the needle of the compass points to a magnetic north pole.

That is incorrect as the GEOGRAPHIC NORTH POLE is actually the MAGNETIC SOUTH POLE disregarding magnetic variance or declination.

This is a very common mistake and is actually incorrect in many texts and on many websites. Think of the compass needle as the "Geographic North Seeking Pole" of the compass magnet.

Vaguely remembering that before I shot this video I looked it up online only to find some of the incorrect websites.  Only later when I built this polarity detector https://youtu.be/5NTch0j1gts  did I find my mistake.



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Determine magnetic polarity of a magnet or coil with this cool feature on the Bartol Mag-Probe.
Mag-Probe noncontact test probe.
Check out our other Videos:
https://www.youtube.com/user/KGitteme...

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From  http://bartolmagprobe.com

When using the high/low sensitivity ring, the
“Mag-probe” becomes sensitive to north and
south poles. White dot toward the “Mag-
Probe’s” tip detects North. When the ring is
removed and installed with the white dot on
the ring towards the “Mag-Probe’s” LED,
you'll detect only south poles. ! !
DC powered devices can be connected to a
power source two ways.!
(See figure 6A and 6B) !
! In figure 6A, assume that a
north pole occurs
at the coils upper end when a DC voltage is
applied as shown. If the polarity of the
applied voltage is reversed as shown in
figure 6B, A South Pole is generated at the
upper end. Try both ends of an operating
solenoid, relay, reed relay, or DC device.
Once you establish which end of the relay or
DC device causes the “Mag-Probe” to
operate, the other relays or DC devices
installed in the instrument under test should
respond at the same end. (See figure 7)!