Testing of Coils in Pulse Motor

Three coils are tested here. Each coil contains exactly 50 feet of 22 gauge wire on 3 1/4 X 3/8" bolts. Each bolt, nut and 2 nylon washers were weighed to check for consistency. They all weigh 1.90 ounces. The coils are made exactly the same, except for how they are wrapped.

Coil 1 is a normally wrapped full length coil. Wrapped from bottom to top, top to bottom.
Coil 2 is wrapped full length except the wire is pulled down (see wrapping coils here) so all wraps go from bottom to top.
Coil 3 is wrapped like coil 2 except each layer is staggered making the coil conical in shape.


The repulsive force of each coil is measured with a lever and a digital scale. One end of the lever has (2) 1" magnetic disc glued to it. When the coil is powered, it pushes against the magnets, which in turn push down on the digital scale. The coil voltage is controlled from a Precision power supply. The coils are supplied with 12 volts, at 2.5 amps. Below is the Setup.

Click any Image to see a larger version.

Coil 1 Results Coil 2 Results Coil 3 Results
1.55 ounces of Force for Coil 1 1.35 ounces for Coil 2 1.45 ounces for Coil 3
The next test was to test each coil in a small pulse motor to see what the RPM is. The setup is unchanged for each coil. The coils are drawing 12 volts at 1.2 amps.The pulse HZ was measured with a frequency meter and confirmed with a oscilloscope. The Motor setup is below. The rotor has 4 double stacked 1/2" disc magnets.

Coil 1 -  153 div by 4 magnets =38.25 times 60 seconds = 2295 RPM. Coil 2 -  162 div by 4 magnets =40.5 times 60 seconds = 2430 RPM. Coil 3 -  176 div by 4 magnets =44 times 60 seconds = 2640 RPM.


Coil 1 appears strongest for repulsion, but is weakest for running the motor. Coil 2 is weaker than coil one for repulsion, but stronger for running the motor. Coil 3 is stronger than coil 2, but weaker than coil 1 for repulsion, but clearly the best for running the motor with a gain of 345 RPM over a standard coil.
Finally, the way the coils are wound are probably influenced by the shape of the magnetic field and affects how it repels in the presence of a small permanent magnet disc. It appears that a conical coil is better for pulse motors, but a standard wound coil would be better for say a solenoid.
More test coming - photos of the coils magnetic fields, with and without the presences of a magnetic disc, and how Ferro fluid is affected.

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