Wire gauge ?

[Tinkerer]

COIL CALCULATOR

The image is identical, but the CALCULATE button does not show. Only a small place marker that does not react.

Simonbaker,
Maybe you want to compare the calculator results with the ones obtained with Misc.EL http://www.miscel.dk/MiscEl/miscel.html
Tinkerer

[simonbaker]

The image is identical, but the CALCULATE button does not show. Only a small place marker that does not react.

Simonbaker,
Maybe you want to compare the calculator results with the ones obtained with Misc.EL http://www.miscel.dk/MiscEl/miscel.html
Tinkerer

Hi Tinkerer:

1. Which coil type do you use for calcs with MiscEl?

2. Funny - I can't find a button to do the calculation! Clues?

Regards,

-SB

[Tinkerer]

Hi Tinkerer:

1. Which coil type do you use for calcs with MiscEl?

2. Funny - I can't find a button to do the calculation! Clues?

Regards,

-SB

Misc.El = Air coil = Loop Circular = Analyze
Just enter the numbers there is no calculate button on this one.

Do it once with the accurate copper wire diameter and then again with the total wire diameter, including the insulation. the insulation calculation is to get the bundle diameter.

Tinkerer

[Qiaozhi]

Wrong ones!

Of course I put in diameter instead of radius.

Try again.

My coil is about 26 cm in diameter. About 111 turns. 30 gauge enameled wire.

D = 260 mm, R = D/2 = 130mm, Nturns = 11, wire thickness .2546 mm.

Lcalc = 8.111 mH
Lmeas = 12.3 mH

So now I'm back to underestimating by about 30%.

Results for inner coil:

D = 155 mm, R = D/2 = 78mm, Nturns = 100, wire thickness .2546 mm.

Lcalc = 3.603
Lmeas = 4.24

Closer, but other calculators do better on it too.

Maybe I'm wrong about coil parameters. I'll have to wind some new ones carefully and try again.

Cheers,

-SB

Are you using enameled wire or something else?

[Qiaozhi]

The image is identical, but the CALCULATE button does not show. Only a small place marker that does not react.

Is anyone else having this problem, or is it just Tinkerer?

It sounds to me like you don't have Active Content enabled in the browser.

[Qiaozhi]

Wrong ones!

Of course I put in diameter instead of radius.

Try again.

My coil is about 26 cm in diameter. About 111 turns. 30 gauge enameled wire.

D = 260 mm, R = D/2 = 130mm, Nturns = 11, wire thickness .2546 mm.

Lcalc = 8.111 mH
Lmeas = 12.3 mH

So now I'm back to underestimating by about 30%.

Results for inner coil:

D = 155 mm, R = D/2 = 78mm, Nturns = 100, wire thickness .2546 mm.

Lcalc = 3.603
Lmeas = 4.24

Closer, but other calculators do better on it too.

Maybe I'm wrong about coil parameters. I'll have to wind some new ones carefully and try again.

Cheers,

-SB

I downloaded MiscEL and ran a comparison on SB's data:

In CoilCalc I entered:
Inner Radius = 130mm
Wire Thickness = 0.2546mm
Number Of Turns = 111
Results calculated as:
Mean radius = 132.66mm
Coil Thickness = 5.32mm
Inductance = 8.111mH

In MiscEL I entered:
Kind = Loop circular (Simple)
Selected Analyze
Turns = 111
Diameter (min) = 260m
Wire diameter = 0.2546
Bundle diameter = 5.32m
The result was:
Inductance = 8.707mH

Since MiscEL expects everything to be in meters, you have to enter an extra 'm' to switch to mm, except for the wire diameter.

SB has measured 12.3mH for a real coil with this number of turns. It would be interesting to know what wire type was being used, as both these calculators presume the use of enameled copper.

[nakky]

Is anyone else having this problem, or is it just Tinkerer?

It sounds to me like you don't have Active Content enabled in the browser.

Qiaozhi ,thanks I like it works perfect.Grt Nakky.

[Tinkerer]

Is anyone else having this problem, or is it just Tinkerer?

It sounds to me like you don't have Active Content enabled in the browser.

How do I enable Active Content? Is anybody else using Vista Home Basic?

Tinkerer

[Qiaozhi]

Here's where I originally found the information about Brook's equation ->
http://info.ee.surrey.ac.uk/Workshop...air_coils.html

And here's the formula I'm actually using in CoilCalc:
L = 4×10-7πa N2((0.5+S1/12)ln(8/S1) -0.84834+0.2041S1)

[simonbaker]

I downloaded MiscEL and ran a comparison on SB's data:

In CoilCalc I entered:
Inner Radius = 130mm
Wire Thickness = 0.2546mm
Number Of Turns = 111
Results calculated as:
Mean radius = 132.66mm
Coil Thickness = 5.32mm
Inductance = 8.111mH

In MiscEL I entered:
Kind = Loop circular (Simple)
Selected Analyze
Turns = 111
Diameter (min) = 260m
Wire diameter = 0.2546
Bundle diameter = 5.32m
The result was:
Inductance = 8.707mH

Since MiscEL expects everything to be in meters, you have to enter an extra 'm' to switch to mm, except for the wire diameter.

SB has measured 12.3mH for a real coil with this number of turns. It would be interesting to know what wire type was being used, as both these calculators presume the use of enameled copper.

It is 30 gauge enameled magnet wire I'm pretty sure.

I made it a while ago and all I can think is I'm mistaken about number of turns, although I typically make coils between 100 and 110 turns.

I hope to do some experiments winding a bunch of coils and get some good trustworthy data. These coils I did not bind tightly, but the large one is wound in a slot that makes it pretty compact.

Also, no problem here running Q's calculator, Windows XP, IE7.

Regards,

-SB

[simonbaker]

Misc.El = Air coil = Loop Circular = Analyze
Just enter the numbers there is no calculate button on this one.

Do it once with the accurate copper wire diameter and then again with the total wire diameter, including the insulation. the insulation calculation is to get the bundle diameter.

Tinkerer

Where is inductance displayed in MiscEl? I don't see it?

-SB

[Qiaozhi]

How do I enable Active Content? Is anybody else using Vista Home Basic?

Tinkerer

Vista Home ... that's your first mistake.

But seriously, I can check this tomorrow on another computer, unless someone gets there before me.

Have you only tried Google Chrome? How about Firefox, or (cough) Internet Explorer?

[Qiaozhi]

Where is inductance displayed in MiscEl? I don't see it?

-SB

Top right:

[Tinkerer]

Vista Home ... that's your first mistake.

But seriously, I can check this tomorrow on another computer, unless someone gets there before me.

Have you only tried Google Chrome? How about Firefox, or (cough) Internet Explorer?

Vista Home was the only choice. I bought this laptop in Switzerland. It has this weird keyboard characters and is all different. Then it suffers from a language problem, it is not capable to work properly with 4 different language software. Bad buy.

I opened your coil calculator with Firefox. The Geotech page took 10 minutes to open, but the coil calculator worked fine.
There is a difference in the inductance, that is probably due to the fill factor that MIsc.El uses.

So the problem is with Google Chrome. For me it is about 5 times faster but it has still a few small problems. It is a Beta version anyway.

Tinkerer

[simonbaker]

Top right:

Whoops - problem was I also filled in wire diameter -- over-specified! Only fill in red fields is the rule -- probably obvious to anyone with good fashion sense...

(Another rule - in some inputs, must have leading 0 before decimal fractions, e.g. "0.2546", not ".2546"! obvious???)

Now I'm getting a little closer with MiscEl:

Multi-layer, N=111, L=3m, Dmin=260m, Dmax=262m, Inductance= 10.23 (compared to 12.23 measured).

Using "current sheet" formula with same params gives Inductance=10.77.

Let's try tweaking parameters in multi-layer:

Multi-layer, N=111, L=.5m, Dmin=260m, Dmax=262m, Inductance= 12.21 (compared to 12.23 measured). Exact!!! But unrealistic coil length.

So the beat goes on...

Cheers,

-SB