Magnetic fields within a toroid inductor.

[Dave45]

Lets say we have 2 toroid cores and wind them the same. Then use a ferrite rod through the toroids centers like an axle with wheels. I wonder if input to one would induce the other? Just thinking. If we can run 1 wire through the toroid, equal to 1/4 turn, really, and get output from that wire, then why not see if we can draw out any flexing fields from one core to another via an axle core.  Also, how would a core in the hole of a toroid affect the toroid coil function, or value. All things to try.

Your wheels need spokes and spin 

Good morinin America how are ya, dont ya know me Im your native son 

[hanon]

Hi all,

This video is very enlightening:

http://www.youtube.com/watch?v=haez8oojjDo

Regards

[Magluvin]

Here is one I like. It has an odd twist to the winding of the secondary.

http://www.youtube.com/watch?v=AaYOph1I3uw

Mags

[Magluvin]

Still havnt gotten my hall sensors.    New tracking date is the 3rd. But thats not news. 

But this is.  Below is some pics of parts on a circuit board from a high end electric wheel chair motor control box. My buddy works on these things and gave me some out dated stuff. Anyway, there are 4 of these small cores with the thick wires as you see. But, the lil white stripe is a marking on the top of a hall sensor. They look to be measuring currents on the outputs to the motors. Never seen that before.  So Im going to remove the sensors this weekend and try some things. One pic is of the bottom of the board where you can see the thick wires soldered and the 3 little soldered leads(hall).  Pretty cool idea.

Just thought that might be interesting.

Mags

[gyulasun]

Hi Mags,

Yes, this solution is indeed interesting, not seen yet such either.  If I can see it correctly the sensor is placed into the air gap of a toroidal core and any current change in the heavy wire that the motor initiates would appear as a flux change in the gap of the core.
It is a kind of a current transformer without output coil.
If the exact type of the Hall sensor cannot be identified then you need to assume two things: whether it gives a linear output which is proportional to the flux change (i.e. current change) or it gives a digital low or high above a certain flux strength for initiating certain switching interaction (say due to overcurrent). 

Gyula