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Regulated power supply on lead battery bank

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MikeM, you hit on the key aspect of the question here.... that is, do the regulated power supplies have built-in current limiting so that when driving into that 23v low-impedence battery, does it see a short circuit and shut down, or does it go to full current, full power and just stay that way.

It depends on the supply. I recently bought some 15V 40A switchers on ebay. I set the output voltage to 14.2V and connected one to a discharged flooded-cell car battery. The supply has overload protection, which caused it to drop out of regulation at about 42A ( the output waveform got a lot of ripple on at the switching frequency of about 50KHz) but the supply didn't overheat or blow-up. I'm pretty sure that that high frequency ripple is not good for a battery, though.

If I manually turned the trimpot to a lower voltage, the supply happily delivered 40A pure DC to the battery. At any given setting of the trimpot, the current would taper as the battery charged, so to keep the current near 40A I had to incrementally keep increasing the voltage trimpot as the battery charged.

I'm guessing that you could externally sense the output current of the supply, subtract that from a set current less than the supply's current rating, and sum that difference into the supply's control loop, adding a constant-current mode.

I have a Todd Engineering (Power Source) 14V 30A switcher in my travel trailer RV which does have current limiting built-in.

I routinely use a large lab supply which has independently adjustable output voltage and current as a battery charger. For battery equalization, I use the constant-current mode of the supply, during which the battery voltage rises to its own level (>15.5V for a six cell battery)
 
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That's is great input, MikeMI. Since you bring up 12v supplies, that made me think of computer supplies... and many of those are now power factor corrected (APFC) to 90% to meet "Energy Star" specs. That means, if I can put these in series for 24v, I could almost double the available power from my wimpy generator. All the 23v regulated supplies I see are very low pf.

How to series computer supplies ? ... I hope the negative output is floating... would like to get the voltage up a little , too.
 
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