parallel coil analysis

[Justadude]

So I was watching Rip Tripper make a parallel coil yesterday and something doesn't make sense. He compared his parallel coil to a single wire coil (same gauge, same diameter, same length - coil wise, not wire wise), and it was significantly lower in ohms. But if he's using twice the amount of wire wouldn't that mean that there is more resistance for the electricity to flow through hence the ohm should be higher?

Btw this is for a single coil, not dual. I saw him show the ohm reading and it didn't make sense. Why would a parallel coil with twice the amount of wire have higher ohms than a single wire coil?

 

[SpanishSunday]

I think the statements you make in the second paragraph of your post contradict the ones you made in the first paragraph.

Could you post a link to that video?

 

[93gc40]

In a parallel dual coils the value of each coil are halved. So two 4ohm coils in parallel will yield 2 ohms.

 

[93gc40]

Think of it like straws in a Coke. 1 straw vs 2 straws used in parallel. More straws means more coke with less sucking effort.

 

[blargy]

Just a quick reply. Think of the wire as a roadway and the resistance as traffic congestion. Add another lane and you get half as much traffic.

 

[VHRB2014]

Just a quick reply. Think of the wire as a roadway and the resistance as traffic congestion. Add another lane and you get half as much traffic.

That`s how I explained it to my wife. She said, "ah ha". LOL.

 

[jpargana]

So I was watching Rip Tripper make a parallel coil yesterday and something doesn't make sense. He compared his parallel coil to a single wire coil (same gauge, same diameter, same length - coil wise, not wire wise), and it was significantly lower in ohms. But if he's using twice the amount of wire wouldn't that mean that there is more resistance for the electricity to flow through hence the ohm should be higher?

Btw this is for a single coil, not dual. I saw him show the ohm reading and it didn't make sense. Why would a parallel coil with twice the amount of wire have higher ohms than a single wire coil?

Your first paragraph would be true, if the coils were assembled in series, an not in parallel. In series, yes, you would have twice the resistance because there's twice the coil lenght in the ONLY path electricity can flow. (Rt = R1 + R2)

But in parallel, all things change: not only do you have "the same" coils lenght, but now you have two paths for electricity to run. So, electrical resistance is halved, if both resistances are equal. If they are not, things get a little more complicated: 1/Rt = 1/R1 + 1/R2.

Doing two similar coils in parallel is in fact the same as making a new single coil, this time using a new wire that has 2x the previous section area. Resistance value would also be halved.

 

[Justadude]

Guys here's the link as requested, hopefully it works with embedding:

Parallel Coil Build: http://youtu.be/9MNJuYuwgwI

I understand that the res is cut but what doesn't make sense is if single coil is pushing out .8 as rip said why is the parallel pushing out .25? Shouldn't it push out .4?

 

[Necrotic]

Could be less wraps than on the single. If he did 7 on the single that's 14 for a parallel which is massive

 

[SpanishSunday]

Guys here's the link as requested, hopefully it works with embedding:

Parallel Coil Build: http://youtu.be/9MNJuYuwgwI

I understand that the res is cut but what doesn't make sense is if single coil is pushing out .8 as rip said why is the parallel pushing out .25? Shouldn't it push out .4?

No. The single coil is built without space between spires. The two sub coils in the parallel one are built with a space between spires equal to to diameter of the wire.

Coils with spaced spires are shorter than coils with touching spires, and have less resistance.

You can check that using his useful helix length calculator.

 

[Justadude]

Could be less wraps than on the single. If he did 7 on the single that's 14 for a parallel which is massive

No dude he's got 4 wraps on a parallel coil and I believe 8 on a single

No. The single coil is built without space between spires. The two sub coils in the parallel one are built with a space between spires equal to to diameter of the wire.

Coils with spaced spires are shorter than coils with touching spires, and have less resistance.

You can check that using his useful helix length calculator.

Maybe a dumb question but what's a spire? In this context at least. I did a goggle search for it and got some goofy crap come up.

 

[SpanishSunday]

(...)



Maybe a dumb question but what's a spire? In this context at least. I did a goggle search for it and got some goofy crap come up.

Sorry, English is not my first language, so I tend a bit too much to archaisms, and words with no Anglo-Saxon origins.

From this dictionary:

one of the series of convolutions of a coil or spiral.

Now I think, perhaps "turn" or "loop" is a more usual word.

 

[Justadude]

There is no space between his loops. Not in parallel and not in single.

So let me get this straight - the length of the wire he's using for that parallel coil is half of the length that he's using for a single correct?

Because if that's the case it would make sense why it's quarter the ohms with 2 wires done like that. Or more accurately one wire bent in half.

 

[SpanishSunday]

In the parallel setup the space between the loops of one coil is occupied by the loops of the other coil, so both coils are spaced coils, so when they are put together there is no space between the wires.

That's the same principle that with multiple start (or multiple threaded) screws: