GoldenMotor.com Forum
General Category => General Discussions => Topic started by: Just on February 07, 2013, 06:00:05 PM
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Hi All,
I have 24V 10A charger, but I'd like to limit the charging current to 5A. How could I do so?
Thank you!
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Hi Just,
This is going to sound peculiar, but I've used it many times to limit power available to circuits. Simply put an ordinary household light bulb (s) in series with the load. You may have to fiddle around with some bulb measurements to get the right resistance, about 5 ohms. They are cheap, rugged and reliable.
TTFN,
Dennis
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Simply put an ordinary household light bulb (s) in series with the load
Probably you intended to wrote "in parallel with the load"?
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What kind of your charger do you have any pcitures?
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Similar to this one:
http://stores.headway-headquarters.com/-strse-79/24v7a-lifepo4-charger%2C-lifepo4/Detail.bok?category=CHARGERS
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Maybe you have some luck.
Open the charger and you will see three trimpots for:
Fan shutdown at prefered current.
Chargingging voltage adjust.
Charging current adjust.
I don't which trimpot exactly is for every adjustment.
But just play and hook a up multi meter.
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By placing the lamps (think very high watt resistor) in series with the load you limit the amount of current available for the load. Placing it in parallel with the load would just increase the current draw from the supply.
TTFN,
Dennis
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Maybe you have some luck
Waw! I have a luck! I did not have it already for a long time!
I'll differently try to play with the trimpots! There are exactly three of them there!
Thank you!
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By placing the lamps (think very high watt resistor) in series with the load you limit the amount of current available for the load
What about a voltage drop over the lamp? Will the battery still receive the required charging voltage?
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Open the charger and you will see three trimpots for:
Fan shutdown at prefered current.
Chargingging voltage adjust.
Charging current adjust.
How could I know how many current I can allow? Originally the charger was 48V 5A. Can I set it for 48V 10A? :-)
While adjusting the trimpot of current limit, how could I know how many I allow?
Thank you!
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Yes you can adjust the current and voltage.
Only the issue is heat: so be carefull when choosing higher voltage and current.
How do know the current?
Well just hook up the multi meter or amp clamp meter.
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By placing the lamps (think very high watt resistor) in series with the load you limit the amount of current available for the load
What about a voltage drop over the lamp? Will the battery still receive the required charging voltage?
As you know the voltage drop is dependent on the current (as stated by ohms law V=R*I). When the charger reaches the Constant Voltage stage the current is so low that the voltage drop over the light bulb will be next to nothing. But playing with the pots sounds like more fun.