Hi,
I am using the following magnetic core to make a solenoid of inductance 12u= H (A11)
Part Number: ROD 6/ 20 /3C 90. Its 6mm in diameter, 20.3 mm in length and u= i =3D 2300.
I used the 20 AWG gauge solid wire.=20
You can find the schematic of the circuit at the following link=20 =20
The input to the inductor is 40 V peak to peak sine wave with a frequency o= f 100KHz.=20
Problems:
- The solenoid gets hot after 40 minutes when I put it in the magnetic fie= ld generated by some other coil. I do not know how much magnetic field is p= resent. But the solenoid (A11) is getting hot.=20
The magnetic core is rated for 100KHz and its Hysteresis curve is thin (pag= e 121, Figure 3). I do not know what is going on here. Can anyone give any = suggestions. How can I keep the temperature constant like 20 degrees above = ambient temperature and do not let it increase with time?=20
- Calculation of the self inductance of this solenoid (A11)=20
I found the following formulas on the internet
a) L =3D (u0 x N x N x A ) / l=20
u0 =3D 4x pi x10^-7 A =3D cross sectional area pi x r x r=20 N =3D Number of turns l =3D length of the wire
b) L =3D (u0 x ur x N x N x A ) / l=20
Which one is correct? And if formula b is correct than what will be the val= ue of ur for the core that I am using?=20
jess