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Adjustable Output Power Supply

What should I be looking for in a power supply? I'm building a 12v battery bank now, but eventually may move up to 48v. Would a 50v power supply work for the 48v battery bank?

The post above has me confused. How can a power supply that only goes to 15v charge a 16s battery that is ~48v?

Throwing out an example for discussion, the Rigol DP712 is rated to 50 volts and 3 amps. Is 3 amps enough? Specifications are here.
 
What should I be looking for in a power supply? I'm building a 12v battery bank now, but eventually may move up to 48v. Would a 50v power supply work for the 48v battery bank?

The post above has me confused. How can a power supply that only goes to 15v charge a 16s battery that is ~48v?

Throwing out an example for discussion, the Rigol DP712 is rated to 50 volts and 3 amps. Is 3 amps enough? Specifications are here.
The max charging voltage for a 16s lifepo4 battery is 58.4 volts.
 
The thing that catches people is that 16 cells in parallel takes 16 times longer to charge.
 
So it's possible to charge a 16s (max charge volts of 58.4 volts) at 15 volts?

No the absolute minimum voltage for a 16s lifepo4 battery is 40 volts.
That would essentially be bottom balanced.
 
So how did BigVT (in post #21) charge his 16s battery with a charger that only goes to 15 volts? Did he charge each cell individually? I think that would be rather tedious.
 
So how did BigVT (in post #21) charge his 16s battery with a charger that only goes to 15 volts? Did he charge each cell individually? I think that would be rather tedious.

Usually for top balance you charge as 16p at 3.6 to 3.65 volts and then reconfigure as 16s.
 
So how did BigVT (in post #21) charge his 16s battery with a charger that only goes to 15 volts? Did he charge each cell individually? I think that would be rather tedious.

BigVT's charger is rated for 60 amps and his cells are 280ah capacity.
I would make 16p and charge them all together.
His charger is rated for 60 amps so I would chank it up to 45 amps and check it periodically to see how hot its getting.
Batteries are usually shipped ~50% charged so ~2240 amp hours is required which would take >50 hours.
 
BigVT's charger is rated for 60 amps and his cells are 280ah capacity.
I would make 16p and charge them all together.
His charger is rated for 60 amps so I would chank it up to 45 amps and check it periodically to see how hot its getting.
Batteries are usually shipped ~50% charged so ~2240 amp hours is required which would take >50 hours.

I see power supplies are rated to 3 amps. Given your numbers, it seems that a power supply with such a small amp rating would be like watching paint dry. In fact, I think paint would dry much faster than a 3 amp power supply trying to charge a 16p battery bank.

How's this for a summary?
High amps, low volts = optimal
Low amps, High volts = workable, but not ideal
High amps, high volts = ideal (but a quality unit is going to be expensive)
 
I see power supplies are rated to 3 amps. Given your numbers, it seems that a power supply with such a small amp rating would be like watching paint dry. In fact, I think paint would dry much faster than a 3 amp power supply trying to charge a 16p battery bank.

How's this for a summary?
High amps, low volts = optimal
Low amps, High volts = workable, but not ideal
High amps, high volts = ideal (but a quality unit is going to be expensive)

@FilterGuy has a good system here https://diysolarforum.com/resources...ls-using-a-low-cost-benchtop-power-supply.65/
 
Sometimes I need a good whack between the eyes with a 2x4.
Sometimes I think I already had the good whack and it killed one of the two good neurons left after my college drinking days. ?
 
I see power supplies are rated to 3 amps. Given your numbers, it seems that a power supply with such a small amp rating would be like watching paint dry. In fact, I think paint would dry much faster than a 3 amp power supply trying to charge a 16p battery bank.

How's this for a summary?
High amps, low volts = optimal
Low amps, High volts = workable, but not ideal
High amps, high volts = ideal (but a quality unit is going to be expensive)
High amps, high volts = high power = big bucks :)
Here's a 160 volt, 7 amp supply I used to have, picked it up cheap, but it was originally a pricey unit.IMG_0268.JPGIMG_0267.JPG
 
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