Ferrite inductors have a ferrite core. Ferrite is a class of ceramic material with strong electromagnetic properties such as high permeability in combination with low electrical conductivity. Ferrite inductors are deployed in a variety of electric circuit applications such as broadband, power conversion and interference suppression.
Things You'll Need
- Inductance meter
Make a simple ferrite inductor by wrapping at least 20 turns of wire around a ferrite rod. Using an inductance meter, measure the inductance of that rod. Record the inductance as "L" and the 20 turns as "N."
Calculate the AL value of the ferrite inductor. The AL value is the base relationship between the inductance, with a given ferrite core, and the number of turns. Calculate the AL value using the following formula: AL = [(100/N)^2)] x L.
For example, if your measured value of L in Step 1 is 25 uH, the corresponding AL value will be: AL = [(100/20)^2] x 25uH =( 5^2) x 25uH = 25 x 25uh = 625 uH.
Use your AL value to calculate the inductance for various values of N using the following formula: L = AL/[(100/N)^2].
For example: If N is 15, L = 625/[(100/15)^2] = 625/[6.66^2] = 625/44.4 = 14uH.
If N is 25, L = 625/[(100/25)^2] = 625/[4^2] = 625/16 = 39uH.
If N is 30, L = 625/[(100/30)^2] = 625/[3.33^2] = 625/11.1 = 56.3uH
As you can see, the inductance increases as N increases. This is because by placing more turns of wire around a loop, it concentrates the magnetic field into a smaller space, where it can be more effective and create more inductance.
- Photo Credit Hemera Technologies/PhotoObjects.net/Getty Images
How to Calculate the Reactance
Resistance is a value to show the opposition to current flow in a DC circuit. It is calculated using Ohm's Law, where...
How to Measure Inductance of a Coil
Inductors are sometimes wound by the user instead of bought. In such cases, the inductance would not be stamped on the side...
How to Calculate the Inductance of a Coil
Coils are inductors–they resist the flow of alternating current. This inductance is accomplished by magnetically shifting the relationship between the voltage (how...
How to Calculate Series Circuits
Series circuits are a useful starting-off point for understanding more complex circuits. Even the mere introduction of an alternating current source can...
How to Make a Ferrite Inductor
Inductors are electrical components that store electrical energy. This characteristic allows inductors to alter the waveform of an AC signal or to...
How to Calculate Inductor Wire Length
Inductor wires are used in electrical circuits to store energy which builds up during the passage of electrical current. Inductors can also...