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  1. #1
    Senior Member PatrickGSR94's Avatar
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    Can I charge my lights with my old Moto Razr charger?

    My Cygolite Expilion came with a wall adapter that says it puts out 0.18A Max @ 5 volts. I have a charger from my old Motorola Razr phone ca. 2005, and it says 5V 550mA, or 0.55 A. Is there any problem using that charger with my Cygolite Expilion or Hotshot? I would assume it would charge a little faster with .55 amps than it would with 0.18 amps, no?
    2011 Felt Z85 105 | Ultegra | KMC | Selle Italia | Vuelta | Topeak
    90's-ish KHS Alite 1000 MTB, *hybridized*

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    The Recumbent Quant cplager's Avatar
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    It ought to be fine. I have yet to encounter any USB charger that didn't work with any device (except some chargers that supposedly charged multiple devices but didn't put out enough juice for all of them).

    The amperage of the charger shouldn't matter unless the load of the battery is big enough that the voltage drops because of it (although that may be what actually happens).

    Keep track of how long it takes to charge with which charger and get back to us.

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  3. #3
    Senior Member Looigi's Avatar
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    Quote Originally Posted by PatrickGSR94 View Post
    My Cygolite Expilion came with a wall adapter that says it puts out 0.18A Max @ 5 volts....
    Incorrect. That's .18A max for line input. OUTPUT is rated at 700 mA.

  4. #4
    Senior Member PatrickGSR94's Avatar
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    Oh yeah oops, I read it on the wrong line of the label. So I guess the Moto Razr charger at 550mA would actually take longer to charge the light.
    2011 Felt Z85 105 | Ultegra | KMC | Selle Italia | Vuelta | Topeak
    90's-ish KHS Alite 1000 MTB, *hybridized*

  5. #5
    Senior Member Looigi's Avatar
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    Quote Originally Posted by PatrickGSR94 View Post
    Oh yeah oops, I read it on the wrong line of the label. So I guess the Moto Razr charger at 550mA would actually take longer to charge the light.
    It might, but it depends on how much the light actually draws when charging, the charger circuit and the charging circuit in the light. You can get 1+A USB chargers that plug in to the wall and chargers that plug into cigarette lighters for a few bux each. I have a 4 outlet 2A wall USB charger that works worldwide and I keep plugged in to charge my phone, GPS, lights, etc.. I think it was ~$10. I bring it when I travel and also bring a 2 outlet 1A cigarette lighter charger.

  6. #6
    Senior Member PatrickGSR94's Avatar
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    Yeah I just picked up some little replacement cig lighter adapters with a USB plug on it, for each of our cars. It says it puts out 1,000 mA.

    The only way to know what charges faster would be to run the light for the same length of time in the same conditions, then plug it into each different charger and see how long it takes to fully charge. And well, I just don't have the time for that so I just charge the stuff overnight and go with it.
    2011 Felt Z85 105 | Ultegra | KMC | Selle Italia | Vuelta | Topeak
    90's-ish KHS Alite 1000 MTB, *hybridized*

  7. #7
    Senior Member Looigi's Avatar
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    Often, if a charger can't supply sufficient current, its output voltage drops below the point where it will charge at all. In that case, a charger with insufficient current capacity won't charge at all. Some charger may also have a circuit which shuts it down if too much current is being drawn.

    Now, it is possible for a sophisticated circuit in the device being charged to sense the charger's voltage decreasing under load and reduce current draw to that which the charger is capable of. I don't know if the Expilion 700 light has such a circuit.

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