Inductor measurement

[Al.M]

Hi All

Is there a way of measuring or estimating accurately inductors within a speaker crossover without desoldering them from the crossover board?

One way perhaps is to count the number of turns across and deep, check wire thickness and aircore diameter and compare this with any online inductor calculators.

Thanks

[tinitus]

Originally posted by Al.M
Hi All

Is there a way of measuring or estimating accurately inductors within a speaker crossover without desoldering them from the crossover board?

Thanks

Accurately?

Only with measurements, on out of curcuit component

Even if you can calculate mH value from number of windings, length of wire, winding design, it can change a lot only from how careful the actual winding is done

Estimate?

You may be able to estimate whether its 0.5 or 1mH, 2 or 4mH, 3 or 6mH, 5 or 8mH

[DcibeL]

The most accurate inductor calculator I found online was called Calcoil, but unfortunately when comparing the calculated values to known inductor values that I had on hand, the numbers didn't match closely enough for me to rely on software only for determining inductor values.

I would recommend removing them from the circuit and measuring them. You can find cheap LCR meter on Amazon for something like $25.

[nigelwright7557]

Originally posted by Al.M
Hi All

Is there a way of measuring or estimating accurately inductors within a speaker crossover without desoldering them from the crossover board?

One way perhaps is to count the number of turns across and deep, check wire thickness and aircore diameter and compare this with any online inductor calculators.

Thanks

Yo ucan work it out by removing it and putting it in series with a resistor. Apply an AC waveform and work out what the resistance is from how much ac voltage is across teh resistor and the inductor.

[Ron E]

Count the number of turns axially and radially and measure the length, outside diameter and core diameter. Post here and I'll give you an estimate.

[DcibeL]

Originally posted by nigelwright7557
You can work it out by removing it and putting it in series with a resistor. Apply an AC waveform and work out what the resistance is from how much ac voltage is across the resistor and the inductor.

D'oh! Here's a "Why didn't I think of that!" moment...The things you forgot you learned in school. Simple RL circuit with an unknown.