Current draw

[itsallgood]

I have this small dc buck converter to charge some LiFePO4 cells and it is rated for 3A max. I also have a AC lithium charger rated at 14.5v 40A. Is there any way I can limit the current so it doesn't blow my buck converter or do I have to find a different charger?

 

[efficientPV]

You limit it by not putting it in situation to overloading it and using a fuse or breaker. They can take short time overloads. From China, I wouldn't use it over half that current. They often use maximum device rating and not how it was built for heat dissipation.

 

[gnubie]

The item supplying current to the lifepo4 cells should be current limiting itself. You can get buck / boost / etc boards off ebay that are both voltage regulated and current limited. As efficientPV said, it's all cheap junk so buyer beware.

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[itsallgood]

The item supplying current to the lifepo4 cells should be current limiting itself. You can get buck / boost / etc boards off ebay that are both voltage regulated and current limited. As efficientPV said, it's all cheap junk so buyer beware.

current limited buck for sale | eBay

Find great deals on eBay for current limited buck. Shop with confidence.

www.ebay.com.au

Well I tested the buck converter and the output v was significantly lower than than the input and I couldn't adjust the output as the sparse instructions implied. Sent it back and I will get a variable, regulated power supply instead. On to my next issue ...

 

[efficientPV]

A very low ohm resistor can also be in series to limit current. 1 ohm at 1A would be a voltage drop of 1V, about what a dead cell would be. Just take a little longer.

 

[itsallgood]

Thanks to all.