during last 2 months I spend time to try to DIY a multi tap inductor like steffen done it for his projects. My goal was to obtain 2 segment of 250 mH.
(one between pin 1 and 2, and one between pin 3 and 4) straping pin 2 and 3 I expected to obtain 500mH, right ? wrong! I have obtained 1H.
How it is possible? the answar is in the relation of the number of the turn;
in this case I have made about 400 turn to get 250 mH for a total of 800 turn for 2 segments. So I have understand that the numberr of the total turn of the segment does multiply the series inductance, for about 1/2 times every 100 Turn. So , to know what value I 'll obtain seriesing 2 segment I have to do the followig formula:
N-1 + N-2 /2 = M
Were "N-1" is the number of Turns of the 1st seg.
"N-2" is the number of Turns of the 2nd seg.
"2" is dividend of the 2 series wound
and "M" is the multiple factor
400+400/2= 400; you have to multiple the "L" sum of the 2 seg. 4 times
Ones obtained "M" you have to do math as follow:
L-1 + L-2 /2 * M= LM
were
"L-1" is the inductance of the 1st seg
"L-2" is the inductance of the 2nd seg
"2" is dividend of the 2 series wound
"M" is the multiple factor
"LM" is the value of inductance I will Find
250 mh + 250 mh /2 *4 = 1000 mH
this formula comes true only if we use more then 400 turn for the 2 seg.
M value of 0.5; 1; 1.5; are trascurable
I really don't know what's they behave itself in a toroidal wound, or in a differente shape inductor, mine is a square with E ferrite core,All this thing does metter I think.
this is what I have found till know, but I'm sure there's mutch to know about, (maby some square root, or ? here and there) I didn't found nothig about it, even in Audio cyclopedia if there's guru over there, pleas comment it.
MIK
(one between pin 1 and 2, and one between pin 3 and 4) straping pin 2 and 3 I expected to obtain 500mH, right ? wrong! I have obtained 1H.
How it is possible? the answar is in the relation of the number of the turn;
in this case I have made about 400 turn to get 250 mH for a total of 800 turn for 2 segments. So I have understand that the numberr of the total turn of the segment does multiply the series inductance, for about 1/2 times every 100 Turn. So , to know what value I 'll obtain seriesing 2 segment I have to do the followig formula:
N-1 + N-2 /2 = M
Were "N-1" is the number of Turns of the 1st seg.
"N-2" is the number of Turns of the 2nd seg.
"2" is dividend of the 2 series wound
and "M" is the multiple factor
400+400/2= 400; you have to multiple the "L" sum of the 2 seg. 4 times
Ones obtained "M" you have to do math as follow:
L-1 + L-2 /2 * M= LM
were
"L-1" is the inductance of the 1st seg
"L-2" is the inductance of the 2nd seg
"2" is dividend of the 2 series wound
"M" is the multiple factor
"LM" is the value of inductance I will Find
250 mh + 250 mh /2 *4 = 1000 mH
this formula comes true only if we use more then 400 turn for the 2 seg.
M value of 0.5; 1; 1.5; are trascurable
I really don't know what's they behave itself in a toroidal wound, or in a differente shape inductor, mine is a square with E ferrite core,All this thing does metter I think.
this is what I have found till know, but I'm sure there's mutch to know about, (maby some square root, or ? here and there) I didn't found nothig about it, even in Audio cyclopedia if there's guru over there, pleas comment it.
MIK