20 Amp 15-Volt Meanwell For Smaller Generators

That particular unit says it employs hiccup mode protection on current overload.
http://www.onlinecomponents.com/datasheet/sp32012.aspx?p=11953405

I believe one requires constant current limiting on Overload for depleted battery charging.

This one does, for ~35$

http://pge.powergatellc.com/product_info.php/products_id/5258?osCsid=cq155jso42fiabsv7dj3j81ft3vn314vn0h1v8d11rciqnddat90

http://www.meanwell.com/webapp/product/search.aspx?prod=se-200

My MW rsp-500-15 gets a workout. Just yesterday it held 40 amps for an hour straight charging a fairly healthy starting battery that had been depleted to 9.23v. 14 hours after removal from meanwell, battery is at 13.14v. It was interesting to watch the inline watt meter during the first few minutes. It only wanted 23 amps at first, and voltage instantly rose to 14.45, but a minute or 2 later voltage had dropped to 12.93v and the battery was gobbling up 40 amps.

The idea is to match current potential with charge acceptance of the battery. No this will not replace a converter. It is designed and intended to recharge batteries from a nominal 12.0 voltage start point. If it hiccups 26 times in the recharge, so be it. Wimpy generators are hard to work with because voltage peaks get slaughtered.

mex, i believe that unit will act like my turnigy 1080w, and shut down, but i could be mistaken? the peak current at start up causes the foldback current protection, i believe it is, to drop voltage, and thus current, to zero.

landyacht318 wrote:

My MW rsp-500-15 gets a workout. Just yesterday it held 40 amps for an hour straight charging a fairly healthy starting battery that had been depleted to 9.23v. 14 hours after removal from meanwell, battery is at 13.14v. It was interesting to watch the inline watt meter during the first few minutes. It only wanted 23 amps at first, and voltage instantly rose to 14.45, but a minute or 2 later voltage had dropped to 12.93v and the battery was gobbling up 40 amps.

I'm gonna ask the dumb questions, but maybe they will help someone else who is lurking :).

Until I read the other thread, I thought all meanwells we user-adjustable, for output voltage. But I guess they also have a self adjusting option? And that is the norm, and what you are referring to here? Or are you talking about voltage of the battery, not the meanwell output voltage?

Sorry Naio, did not mean to confuse. This was just a different observation of battery charging compared to what I have observed a hundred or more times now with my adjustable voltage Meanwell and its attached watt/volt/amp meter/counter.

I had the Meanwell set to 14.45v when I plugged it into the over depleted starting battery which had measured 9.23v on my multimeter when the owner dropped it off to me.

I am used to seeing a 50% depleted battery just slowly climb toward 14.X at a solid 40 amps until battery voltage approached the my desired 14.x set voltage of the meanwell, and then amps would taper.

This over discharged 3 year old starting battery instantly rose to 14.45V and it only required 23 amps to get there. But after 30 seconds to a minute of slapping this battery upside its head, the voltage had dropped as the battery decided to stop resisting the meanwell's full available current. It was like removing all the hair and junk obscuring the drain on a sink.

I had heard about this behavior on an over discharged battery, I had just never witnessed it, and it was neat having the tools to watch it occur in real time.

I did notice the battery getting hot at 40 amps, and I wound up dialing the MW voltage all the way down( 13.12v) in an attempt to lessen the amperage. It worked, and the rapidly climbing battery temperature levelled off and began to drop, with a fan on it. I just came back every 15 to 20 minutes and kept bumping up the voltage little by little trying to keep it under 25 amps. Soon it was at 14.45v and I just held that Constant voltage, Absorption stage, for about 6 hours, unmonitored as Friday night occurred. It was only taking 1.23 amps after those 6 hours at 14.45v.



And I will stand by my opinion that one desires constant current limiting on overload, rather than automatic shut down until overload is removed, or hiccup mode on current overload.

But if one is only starting this Meanwell after another charging source has gotten the battery to absorption voltage for a while, then that works too.

I personally wanted an All in one charger, equalizer, and float voltage converter. I got sick of weighing the compromises when comparing/researching other charging sources. I love the MeanWell's freakish ability to bend any LA battery to my will. It cost me 127$ delivered, but I put another ~30$ into it with quieter additional fans, and 1K ohm 10 turn potentiometer, and solder and the Wattmeter inline on 8awg with 45 amp powerpole, was another 25$ or so.

----Distant maniacial laughter fading-----

Thanks Mex, for turning me onto the possibility of a Powersupply as an adjustable voltage, Kick burro manual charger.

Aha! Explained.
Now I have to install a pair of caliper adjustment 10 turn pots on my Megas. Shaky, weak hands with crippled left hand. Ooooooo this going to be honorable butt-scratcher or fling power supply through window odyssey in frustration. I hate being old. It's a quad-core I7 brain coupled to a 286 operating system.

You are absolutely correct about the auto foldback feature making the 20-amp Meanwell virtally useless for battery charging. Well it's back to a Megawatt and starting out at 13.2 volts to keep the generator from hara-kiri. Thanks for correcting me.

Mex, why does one need a small adjustable output power supply to go with a small generator?

For example, why can't a 60 amp Meanwell be used with a Honda 1000i (or even with my Honda EX650) by merely turning the Meanwell's output down to some low enough value - like 14.1 volts - so that the little genny continues to hum along supplying whatever the batteries will accept with only 14.1 volts on their terminals? Just "tune" the power supplies output such that it just begins to load down the small generator but not kill it.

Doing this, one can buy a large Meanwell ... so as to be ready for charging when on hookups or charging whenever a larger generator is available ... but also use it with a small generator.

Your new AGMs depleted to 12.2 resting, will still suck everything the power supply can make, if you cannot lower the output voltage of the power supply to very close to that 12.2, then dial it up slowly until the generator starts struggling.

My Meanwell goes down only to 13.12v, not sure about the MegaWatt.

Either of my group 27 or 31 batteries will take 40 amps, but briefly, when the PS is first hooked up in the 85 to 90% charged range, even when set at 13.12v.
My watt meter records peak amps and minimum voltage.

I just installed a couple of 115 AH AGM deep cycle coach batteries so don't know how they're going to act with our stock 13.6 volt converter under various charging start points.

The two 100 AH AGMs they replaced NEVER would draw anywhere near the full 45 amps available from the stock 13.6 volt converter, so I knew that 13.6 volts was not enough to make those AGMs guzzle high currents from a 12.2 volt SOC starting point. I'm expecting about the same behaviour from the new AGMs.

However, under the higher charging voltages from the alternator, the previous AGMs would begin to drink up the current.

The above scenarios full right in line with what everyone talks about - and the engineering graphs show - regarding how just a bit higher charging voltages can cause lead acid batteries to accept way more charging current .... hence charger faster with higher initial charging voltages.

The above realities of battery charging lead me to believe that by playing with any Megawatt's output voltage adjustment, one can tune it so as to get the best charging speed possible with about any size battery bank with just about any size generator available. Of course, the smaller the generator, the longer the charging time ... you can't tune your way out of that.

A person dpes not need a small power supply with a small generator. Period. But all of the power supplies have fragile hypersensitive trimmer pots that defy easy use. Why they do not fit a 69 cent 10-turn cermet I do not know. But disassembling the power supply to solder in an alternative is not for everyone. Me included. But it has to be done. I purchased caliper dials to fit the 500 ohm Vishay pots so I can dial-in a voltage by numbers. The Borg has a pair. My latest quest is 4-1/2 digit voltmeter and ammeter with 1.1" LED segments. Lools like the 5-amp float will be 13.2 volts fixed.

The 90-amps potential is enough to satisfy any portable responsibility.

Landy sure found out about parchment thin starter battery plates and thermal gain.

With caliper dial and chart the power supplies become very user friendly. Yes mine has an Intermatic 7-hour spring wound timer. I can play this thing any way I want up to 6-hours then the float kicks in. The float is plenty to sustain my BiPAP.

Now I need someone who does electronic repairs to solder in the pots.