I have tried to find in the webpage some answers about measuring AC magnetic field strength in the range above 50 kHz and more with no luck. Sorry, but if someone could help me will be great.
I need to measure intensity or strength of the magnetic field (1 to 50 mT) between 50khz to 300khz aprox. I have some like "induction heater", with different LC ! L= workcoil., Radius = 2 cm copper tube.
I have used a sensing coil in the middle and i have a strong signal, but iI don't know how to calculate the mT i have. The small sensing coil is 10 turn of awg32 cooper wire with radius = 2,5mm. The voltage is about 0.5 volt, and I can see the out put in the osciloscope(sine wave), I cannot measure the currrent of the sensing coil, and at this frequency my ammeter does not work.
Best Answer
As with any coil, induced voltage is N\$\dfrac{d\Phi}{dt}\$.
So, armed with the number of turns (N), the voltage, the frequency and the area of your loop, you can calculate the average magnetic flux density seen by the coil.
The coil should be measured open circuit and the fewer turns the better because coil parasitic capacitance can easily resonate the circuit and give big errors.