Got a generator today - Now a question

Discussion in 'Motorized Bicycle General Discussion' started by Racing421, Jan 15, 2009.

  1. Racing421

    Racing421 New Member

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    All this "white wire" stuff gives me a headache! I just don't want to dilute any juice to my spark, so I am planning on connecting this 12 volt generator/front/rear light kit.
    The generator has two taps, "T" and "H" and if my ohmmeter is right, it appears the "T" is ground (no resistance from the "T" to the shell of the gen.
    Can anybody tell me what these two letters stand for?
    Also, since this generator is made for a conventional bike, I was wondering if the higher revolutions could cause the lights to burn out prematurely. Maybe I could attach a larger wheel to slow the RPS down. Anyone have any experience with this?
     
  2. Racing421

    Racing421 New Member

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    Just to add something to my previous post..........I purchased a 12v sealed lead acid battery that I want to tie in to the 12v generator.....Do I need any type of voltage regulator circuit or can I just wire the dynamo directly to the battery?
     
  3. Motormac

    Motormac New Member

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    We have to assume here that the generator is putting out 12 volts? Is there a picture of this generator or a link to a picture? Im pretty sure H is the hot wire and T is negative.
     
  4. MB-Monkey

    MB-Monkey New Member

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    Currently i am working on a simple 12V inclusive circuit for Head/Tail (flashing) and turn signals. The 12V sealed battery will run your circuit, but not sure if the generator would "charge" the battery.

    Higher RPMs should not generate more than 12v as i am sure that is the MAX output for the unit; therefore, your lights should not burn our prematurely. (thats a nice compound sentence)

    As for the "T and H" logic would dictate, since it is a duel light setup, that the "T" would be for TAIL LIGHT and the "H" would be for HEAD LIGHT. The ground would be completed by mounting the units.

    Hope this helps
     
  5. Youngbird

    Youngbird Vendor

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    Racing421....T=Tail and H=Head. Pretty sure the lights and the gen. ground to the frame. DUH for me....guess I should have read all the way down, sorry.
     
    #5 Youngbird, Jan 16, 2009
    Last edited: Jan 16, 2009
  6. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    #6 5-7HEAVEN, Jan 16, 2009
    Last edited: Jan 16, 2009
  7. Racing421

    Racing421 New Member

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    Thanks! I never thought it would be for head/tail. When I see two taps, I'm thinking positive and negative...........Are you sure the T doesn't stand for "Taiwan Ground" and the H for "Hong Gaw Positive?"
    Now I'm thinking I will tap both H/T and run them straight to the battery Positive, then power the lights thru a switch back to the battery.
    If anyone can shed some light (no pun intended) on whether this 12v dynamo (yes, it is marked 12v 6 watt) will charge my battery?
    I can't think of any reason why it wouldn't.
    Thanks again for all your help!!!!!!!!!!
     
  8. MB-Monkey

    MB-Monkey New Member

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    well i was discussing this with the wife as a sounding board so take that in mind.

    A 12V may require more voltage then the generator can put out. For instance, In a car setup the battery runs at 12V but the Alternator runs at 13.8V enough to place energy back into the battery. Saying that, with a 12V supply to the battery you would not discharge your lead battery as fast but eventually it would need to be put on a full recharge. I would think it should hold a good usable charge for days if not weeks with the 12v Gen hooked up to the leads.

    This also solves the issue of the lights dying when stopped so i would wire the lights thru the switch to the battery and see if the gen saves the charge in the lead battery. even a small seal battery should run a light setup for days before discharge.
     
  9. Racing421

    Racing421 New Member

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    Thanks, Huffy!
    The sealed battery I ordered is a 7.5 amp hour SLA, and they claim it can be charged hundreds of times. It's only 6"x2.6"w x 3.6"tall...........Maybe I'll spin the 12v generator with a drill (not too fast) and see how many volts it puts out at higher RPMs..........I'll let you all know.
     
  10. Racing421

    Racing421 New Member

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    OK, I just had a moment of concern................If I hard wire the generator to the battery, is there any issue with the generator "draining" the battery while the bike sits in the garage???????????
    I just don't know if the generator creates resistance while sitting at idle. I'd hate to drain a good battery to find this out. I could always put a switch to break the positive going to the generator, but I don't want to do this needlessly.

    Help!!!!!

    I know, I have way too much time on my hands, thanks to the "W" economy.
     
  11. Large Filipino

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    In a car your engine would stop running with your battery disconnected I'm sure there's a way to disconnect your battery and keep the engine running but the way it's set up it don't do that coil something I've worked on cars all my life and I forget the exact reason I know it's electrical.
    But on your bike the battery only does your lights engine don't depend on it so the 12 volts output from the generator should be plenty. I'm not an electrical expert but I'm pretty sure though the amount of OHMS that generator puts out is important. Too much and you'll fry your battery but that thing is tiny so it may give your battery a trickle charge but check your acid levels frequently if it needs water often then it's overcharging. If not then your golden. You'll get your charging during the day and your lights at night just run it always connected and your good. Of course if you add a booming system you may need more.
    To check for a short in your generator or to see if it may drain your battery when resting just get one of them cheap test lights with an aa battery in the circuit and touch the two connectors on your generator at rest to one wire then the other wire to the generator body which is ground. If it lights then yes you will drain your battery at rest. If it doesn't light up you're golden.
     
    #11 Large Filipino, Jan 16, 2009
    Last edited: Jan 16, 2009
  12. MB-Monkey

    MB-Monkey New Member

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    the generator should be at idle when at rest i would not think it would draw on the battery while in the garage
     
  13. old motorbike

    old motorbike New Member

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    Use a diode on the feed wire. That's what I'm going to try.
     
  14. MB-Monkey

    MB-Monkey New Member

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    yes you can put a diode in line with the feed wire to the battery radio shack has them. also make sure you only run 1 lead either H or T not both to the battery as you would be charging 2X12V
     
  15. Racing421

    Racing421 New Member

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    Hey Huff, I did some more checking/testing on the generator today........FYI, the bullet light kit/generator package from Bikeworld (Taiwan) has the two taps H and T. When I hooked up the tail light to T, it burned OK. When I hooked it up to H, it got extremely bright. I unscrewed the bulb, and sure enough, the lamp in the tail light was a 6 volt bulb!
    Which leads me to believe this generator is putting out both 6 and 12 volts!
    I'll tap the H (12 volt) and wire to the + to charge the battery. I'm still not sure about the diode thing. WHY do I need it? What does it do?
     
  16. MB-Monkey

    MB-Monkey New Member

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    just put a meter on the generator at idle and look for draw i wouldn't worry about the diode unless you need it.
    a diode just blocks energy from returning down a line makes it "one way"

    Good to know that it puts out both 6v and 12v hook up the H to the 12v lead on the battery
     
  17. blueovalguy

    blueovalguy New Member

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    Youngbird is right, the "T" is for tail light, "H" is for head light. Ground is when it is mounted to the frame and through the lights mounted to the metal frame. I am also working on some type of rechargeable light system so that I will still have lights when I come to a stop. If I come up with something workable I'll post all the details.
     
  18. Racing421

    Racing421 New Member

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    Update on generator/battery/lighting system:

    * The generator DOES have resistance at rest. In order to keep the battery from draining at rest, there is a simple switch that sends power to the lights and at the same time links the generator via a diode to battery positive. When the switch is off, continuity is cut off to the lights AND generator.

    * I added a brake light switch that works off of the rear brake caliper. (I have way too much time on my hands.) I found this motorcycle tail light setup on ebay for $10, and with the dual filament bulbs and connectors, the brake switch made sense. It's a simple momentary off switch from Radio Shack. I hope it works! As the brake pads wear, I'll probably have to do some tweaking on it.

    * To reduce RPMs on the generator, I glued a section of 3/4" ID rubber hose to the generator wheel. This reduces the spin on the generator wheel by about one third, and has the added benefit of not chewing up the tire sidewall. Maybe it will stay on at high RPMs.

    * I like the 7.5 AH battery that arrived yesterday...........It's small, but should do the job. I'm most interested to see how the 12v generator keeps a charge on the battery.

    I'll do an update to let everyone know how all this fares in the real world!
     

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  19. 2door

    2door Moderator
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    Racing,
    Not related to lights or dynamos, but I was noticing your sprocket mounting to the rear wheel. I don't see the rubber donuts that most of us use. How do you keep the sprocket stationary? Is there a hub I can't see?
    Tom
     
  20. MB-Monkey

    MB-Monkey New Member

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    looks like the battery should do well i am working with a wet battery once it is setup we can compare run times i plan on using a battery tender to keep it charged but don't figure i will have to plug it in that often. i thought about the generator charging as well keep us posted please
     

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