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Active Contributor

Join Date: Oct 2007
Posts: 24

Electromagnet Design (Not a School Project)

08/10/2012 11:36 PM

Dear friends.

First For those who think i am asking for to do my homework.its not a school project i already finished my school 6 year ago. actually i finished my project successfully. For the documentation and calculation i need your help. i am good in practical but not so good in theory. that's why i asked for help.you can see my linked in profile. My project is 1.5 kva power is generated by ordinary combustion engine with out any fuel.i finished project.

i have to build a electromagnet in my project at following constraints.

1: I have core Ms grade 40.

2:Diameter is 30 mm not more then it.

3:Length have no constraint, can be more then 3 inches.

4:DC source 12 Volt 60Ah Car Battery.

5: Maximum Ampere not more then 2 A at 12 volt.

6: both poles are at opposite sides. through thickness of Core.

Kindly tell me coil data and length of core required to get Repel force of that electromagnet on N35 of 30mm * 30mm Piece should be 100 ponds. at 0.1 inches and at 38 mm more then 10 pounds.

I need to repel N35 of 30mm * 30mm Piece with that electromagnet. up to 38 mm distance. N35 magnet have repel force on same magnet at the distance 0.1 inches 75 pounds and at 38 mm distance it is 7 pounds.

Thanks for fast reply.

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Guru

Join Date: Oct 2008
Location: 34° 34' 21.60" N, 92° 55' 42.28" W
Posts: 20968
#1

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/10/2012 11:50 PM

I'd like to know how 1.5 kva power is generated by ordinary combustion engine with out any fuel

Please explain the above. Your urgent reply is needed. Soonest!!!!

I'm afraid you are going to have to fish, fast.

Without any fuel?

Go to you instructor and confess that you have not done any work and your non-project won't get done because you don't have any idea what you are doing.

Maybe they will pity you and get you a tutor.

Do your parents know yet?

__________________
Luck comes and goes. Skill is forever. Intelligence either is, or it ain't. lyn
Active Contributor

Join Date: Oct 2007
Posts: 24
#2
In reply to #1

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/11/2012 12:06 AM

you can see my previous discussions.

Guru

Join Date: Oct 2008
Location: 34° 34' 21.60" N, 92° 55' 42.28" W
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#3
In reply to #2

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/11/2012 12:20 AM

I have.

__________________
Luck comes and goes. Skill is forever. Intelligence either is, or it ain't. lyn
Active Contributor

Join Date: Oct 2007
Posts: 24
#5
In reply to #3

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/11/2012 12:53 AM

i describe my project in schematic in previous discussions

is there any formula to calculate size of core for given gauss and coil data.

i use ohm law to get coil resistance and and select cable.

i use B=Mu*N*I/gap to get gauss.

these things i want to generalize my project because i did all things by the method of do and check so i need to generalize it my work and had to find mathematical method of my project.

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Location: Ketchikan, AK, USA
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#4

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/11/2012 12:33 AM

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In vino veritas; in cervisia carmen; in aqua E. coli.
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#6

Re: Urgent answer required. Electromagnet design ( its not a school Project)

08/11/2012 12:57 AM

My project is 1.5 kva power is generated by ordinary combustion engine with out any fuel.
Do you intend to push/pull the pistons with the magnet?
I have news for you - the power company uses fuel to produce the <1.5 kva electricity you intend to use to turn the IC and gen.
Go back to school and this time pay more attention to theory or get a teacher with knowledge.

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Join Date: Oct 2008
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#7

Re: Electromagnet Design (Not a School Project)

08/11/2012 9:44 PM
__________________
Luck comes and goes. Skill is forever. Intelligence either is, or it ain't. lyn
Member

Join Date: Jul 2012
Posts: 7
#8
In reply to #7

Re: Electromagnet Design (Not a School Project)

08/12/2012 1:40 AM

Hello. Do a search. I found a formula but do not think it complete. But it gives fource at distance takes amps and number of coil turns etc. Don't have have the explanation you might need.

I am trying to make a magnetic latched positioner. The driving force is from springs. Using springs working against each other. So that when it is latched to one magnet the spring fource is unbalanced away from the holding magnet. Switching to the other magnet releases the mechanism and it travales toword the energized magnet where I hope it has enough pull to grab and hold it.

I am a retired software engineer. I started out as a math, physics major collage but took a fortran course and got hooked on computers. But from what I know and have in my old physics books there isn't a simple formula for force of a magnet. Or is there? So I would also like to know if this simple formula:

Fource = 9112.989803*(N*I/x)^2*A

N : number of turns in coil

I : curent

A : contact area

x : distance between contact furfaces

Sorry I don't have the origional formula. I reduced it down for the least number of calculations to use in MathCad. Also for x in inch. A in inch^2, And pounds fource.

But x can never really reach 0 as surfaces at the atomic level never touch. But what would be a good value for the min x. But the question is wether that simple formula works.

I am using VisSim to simulate the magnetic latched mechanism. The contact distance is a parameter and the force at distance is calsulated using the inverse square law, as is the above formula, and combined with the spring fource in a differential equation for the dampaned harmonic motion. Actually an intergration formula as VisSim does intergration much better. I am sure all you engineers know the spring differential equation formula for hormonic motion. Right? Basic Newton.

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Join Date: Dec 2006
Location: Loveland Colorado, USA
Posts: 2413
#9

Re: Electromagnet Design (Not a School Project)

08/12/2012 6:26 PM

You are dealing with engineers here. We are not easily fooled with lies. If your project is finished, then you don't need to calculate the length of the coil core, you just need to measure the one you have. BTW, electromagnets are normally made for attraction not repulsion. Even if we believed you, you haven't given us any useful information to use for you calculation.