How to calculate ohms per coil when the wire states ohms per foot?

[Lung Redemption]

Plonk the gauge into steam engine, set your parameters (ID, targetted ohms) and move the ohms up or down until the calculator displays the desired wraps.

Frankly i think it's easier to work out your build on steam engine first, so you know the gauge you want rather than inversely looking at wires and asking yourself what the build and ohms will come out to.

 

[speedfreek67]

True, but the OP didn't specify the gauge. I'm guessing it's a complex coil, but if you know the resistance over a given length you can calculate a ballpark figure quite easily.

 

[Lung Redemption]

Naturally, can't say i've seen complex coils list a resistance over length though(as numbers can vary), tends to(as far as i've observed) be simple wire that lists per ft resistance.

Simple math has you though, a small amount of division is usually all that's needed (anyone can manage that).

 

[speedfreek67]

I was thinking along these lines..

 

[Lung Redemption]

Divide by 3(1ft is as good as 30cm), take a little off and i have a good ballpark.. personally.

 

[guy]

True, but the OP didn't specify the gauge. I'm guessing it's a complex coil, but if you know the resistance over a given length you can calculate a ballpark figure quite easily.

This. It's the coilology 'multi-strand fused Clapton' I was looking at! Doesn't give information on gauges, only ohms per foot.

 

[nwhornet]

This. It's the coilology 'multi-strand fused Clapton' I was looking at! Doesn't give information on gauges, only ohms per foot.

All their wires state core/wraps

 

[speedfreek67]

Anyone care to use steam-engine to calculate these wires?

I'll stick to my ballpark method (I reckon it's between 0.3 and 0.4 ohms per 5 wrap coil)

 

[nwhornet]

Your method is the easiest with these but, if memory serves you'd enter that as 28awg parallel, the outer wraps don't come in to the equation. Similar results

 

[speedfreek67]

Interesting, using steamemgine a parallel 28g Ni80 coil, 5 wraps, 3mm ID comes out to 72mm long. But it comes out at 2.05 ohms per foot, and says the resistance is 0.48 ohms.

But this wire is 1.73 ohms per foot.

So for 72mm length, thats pretty much bang on 4 ohms.

I didn't add enough to take into account how wide the wire was.