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Help with Toroidal coil value

  1. Aug 6, 2008 #1
    Hey fellas, I blundered onto this forum trying to figure out the value of a coil. I'm building a hydrogen generator and the plans call out for hand winding a toroid coil. I'd like to buy one instead but it doesn't give the value of the finished coil, just how to make it.

    It tells you to use a National Magnetics #995 ferrite core which is 3.5" OD, 2" ID, and 0.5" thick. The wire is 23ga teflon covered and the number of wraps is 2000 (yes, two thousand). I looked up the core and the AL is M-178, M2-57, G-711, H-1208. Core constant is 1.421. I have no idea what these numbers mean, I just took them off the online spec sheet, here...http://www.magneticsgroup.com/pdf/NMG Catalog .pdf

    I'd like to buy this coil already made off the shelf if possible, hand winding 500ft of wire around that little core could quite possible push me over the edge. LOL

  2. jcsd
  3. Aug 6, 2008 #2

    The Electrician

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    Gold Member

    The plans should tell you what material the core is made of, such as M, M2, G, or H. There is a chart at the end of that catalog that shows the properties of the various materials (Ni-Zn ferrite, in the case of these 4 materials). If you knew that your toroid was going to be made of G material, for example, the AL for that core is 711, so you square the number of turns (2000)^2 = 4,000,000 and then multiply that by 711 and get 2,844,000,000 nanohenries (see note 1 at the bottom of the toroid chart in the catalog), or 2.844 Henries.

    The inductor, if you wound it, would have a MLT (mean length of turn) of maybe 4 inches; 2000 turns would give the total length of wire as 4*2000/12 = 667 feet of 23 gauge wire, which would have a resistance of about 13.57 ohms. Such an inductor probably shouldn't dissipate much more that 10 watts in air to be safe, so the current rating should be about 1 amp.

    Looks like you should look for an inductor capable of handling 1 amp, with an inductance of 3 henries. If the 1 amp is all DC, then the core may saturate. I don't know what your circuit will be applying to the inductor, but these numbers should give you a start.
  4. Aug 7, 2008 #3
    The input is going to be pulsed 12vdc and the goal is to saturate it from what I understand.

    As to the material (aha! that's what those letters mean), it seems that is one thing the plans have left out.:uhh: I'll see if the place I bought them can shed some light on that. Customer service hasn't been their strong point.

    much thanks for your help,
  5. Oct 22, 2008 #4
    Did you ever get your coil produced or purchased? I am working on a project that requires the same toroid coil you mention and we are facing the same challenge of making the coil versus buying one.

  6. Oct 22, 2008 #5
    If you are building that Hydrogen Cell, aka "Hydrostar", I found out that it's a well known internet fraud. That plan I bought was available for free from a different source and there are much better free plans out there. The coil they call out in that plan does not do what they claim it to do. Have a gander over at hhoforums.com. They have a lot of helpful folk over there. I have abandoned the HHO experiment because of the cost of 316L steel. I was looking at $200+ just for the material to build the cell I wanted to, not counting the electronics needed to trick the car's computer.

    good luck and pitch out that hydrostar plan if that is what you are looking at. Look into a "dry cell" or a "Tero cell".

  7. Oct 22, 2008 #6
    you're wasting your time using any kind of cell to pump hydrogen into an internal combustion engine. all those "water cars" are pure frauds, not just individual implementations of it. the gasoline your engine uses is a hydrocarbon, and full of hydrogen. water is even one of the byproducts of combustion in the exhaust.
  8. Oct 22, 2008 #7
    Typical response from someone who hasn't researched it. Not going to argue with you, no point.

    good day,
  9. Oct 23, 2008 #8
    Check out hydrostarcar.com forum. Custom coils are building coils at just slightly smaller dia so wound coil fits into cpvc housing inquantity they can be had for 108$$ singles are 168. Also same company is selling them on E-Bay :-) current forumites are setting volume order now and will send when they get to 25 orders. Gare
  10. Oct 23, 2008 #9
    three new members posting on this is one thread looks a lot like shilling to me.

    once again, for anyone reading here. DO NOT BUY THIS. IT IS A SCAM. if you want better mileage, tune up your engine. which is what you'll have to do anyway because these guys don't get results without engine tweaks. but they tune up their engines and VOILA!, better mileage magically appears!

    this stuff has been around for years before gas prices started rising, and you know what? it didn't work then, either. but there's certainly a better chance of selling the scam now, so the marketing has stepped up.
  11. Oct 24, 2008 #10


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    Science Advisor

    Does anyone have any links to articles where any of these units have been reasonably scientifically tested? Personally I very much doubt that they'ed work, obviously from any energy standpoint they can only waste energy but there is always the arguement of increased combustion efficiency or improved combustion profile or whatever. Anyway it would be interesting to see someone do a proper test on one of these units if anyone has a link.
  12. May 30, 2010 #11
    I have seen the system working on a lawn mower and a vehicle. The system requirements are: 1 ferrite toroid coil core, 3.50 OD x 2.00 ID x .500 thick (National Magnetics Part #995); copper magnetic wire, teflon coated, heavy build, 23 AWG, 550 ft. The coil is created from 2,000 turns of insulated copper wire wrapped around a circular magnetically sensitive core. Note double build extra heavy insulation, 23 AWG.

    I have several quotes that I'd like your opinion about: Quote #1:Natl Magnetics Corp. P/N M-995 (3.5x2.0x0.5"); Magnet wire: GP/MR-200 polyester/polyamideimide heavy coating 200 degreeC NW35-C/A; Winding: No final coating and insulation provided. Maximum OD= 3.95"; 2 - S#18/4 leads.

    Quote #2: They have made a couple design changes. Changed the wire used to HML wire not Teflon coated wire. Saying the Teflon is impossible to use in a winding machine as the Teflon scrapes off. The HML is heavily insulated and is used in many high temp/high vibration environments. In their opinion it is much better for this application. We then vacuum impregnate the unit with a 3M epoxy to seal it from the water.
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