Author Topic: Combo rec/reg decreasing voltage?  (Read 905 times)

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Offline greenjeans

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Combo rec/reg decreasing voltage?
« on: September 20, 2019, 08:02:04 am »
Could you lower the voltage coming out of a sealed combo rec/reg unit with a resistor or something before it hits the battery?   I have one that charges at 14.7 volts.  Using a new lithium battery that only wants to be charged at 14v.    Possible?  Or, is a new reg/rec in order?

Curious
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Offline RAFster122s

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Re: Combo rec/reg decreasing voltage?
« Reply #1 on: September 20, 2019, 01:01:29 pm »
Resistor would have to be large power capacity to dissipate the power and it would get very hot. In another life I was a ceramic power resistor product engineer. Not practical as you would have to find a place to put it to prevent accidental burns and its performance is going to vary a little with extremes of ambient temp. The resistance value should not vary but it will see a swing in temp that varies with the heat of summer.
You would be better off buying the correct rect/reg unit than trying to jerry rig something.
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Offline scottly

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Re: Combo rec/reg decreasing voltage?
« Reply #2 on: September 22, 2019, 10:19:29 pm »
No, you can't simply add a resistor to change the regulated voltage. Rick's has a lithium specific regulator/rectifier, and Oregon Motor Parts has an adjustable solid state regulator.
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Offline greenjeans

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Re: Combo rec/reg decreasing voltage?
« Reply #3 on: September 23, 2019, 11:33:07 am »
You guys guessed.  We were hoping to reuse an old rec/reg combo I had for a buddy's bike.  I'll relay the news.  Thanks fellas
Yep, I'm the kid that figured out how to put things back together...eventually.