Battery Equilization PS Current Requirement

[dclark1946]

What power supply current capacity would be required to equalize a single Trojan SCS 200 (Gr 27) 12V battery @ recommended 16.1 VDC?

[dclark1946]

Thanks for all the great input.I found a refurbished 10A Agilent linear PS that had both current and voltage control but it was priced around $600+ and is pretty big so not very practical

[MEXICOWANDERER]

The burning light bulb serves me as a reminder and any NAPA store has them.

[theoldwizard1]

MEXICOWANDERER wrote:
FIVE amps REGULATED AMPS. From starting voltage to 16.0 Volts 5.0 exact amps. Any other recipe is bogus.

You need a power supply that reaches to SIXTEEN volts while maintaining exactly five amperes.

The 26 amp Megawatt will go to 15.85 volts which is close enough.

If you request it in advance, the Megawatt power supplies can be "built" to output 16.1V (at slightly lower than their rated current).

MEXICOWANDERER wrote:
An auto parts store FIFTY WATT trouble light 12 volt bulb will throttle amperage close enough to 5.0 amps as to be good enough.

Placing a light bulb or suitable fixed resistor IN SERIES with the load, if an EXCELLENT way of current limiting any power supply that does NOT have current control. What you really want is a 3.1ohm - 3.5ohm resistor rated at about 75W. (Three 10ohm 25W resistors in parallel would be good.)

If you are going to use a non-automatic charger (which is actually better in some ways), buy a cheap digital voltage/current meter from eBay.

[MEXICOWANDERER]

FIVE amps REGULATED AMPS. From starting voltage to 16.0 Volts 5.0 exact amps. Any other recipe is bogus.

You need a power supply that reaches to SIXTEEN volts while maintaining exactly five amperes.

The 26 amp Megawatt will go to 15.85 volts which is close enough.

An auto parts store FIFTY WATT trouble light 12 volt bulb will throttle amperage close enough to 5.0 amps as to be good enough.

VERY FEW ANYTHING can serve as an alternative to a power supply and a 12 volt 50-watt light bulb

BECAUSE

Which gizmo BRAINIAC converter can rise to 16.0 volts at five amps and maintain the charging specs for hours on end if need be?

I'd love to hear of one, believe me.

And no cake baking for 10 minutes at 2500F

or 9 hours at 175F

Argue with the BCI and my dealing with pallets of sulfated batteries.

The above recipe works. Doesn't damage the battery and is relatively inexpensive to purchase.

Positive wire runs in and out of the base then connects to battery positive.

Yes, this would be a TWELVE VOLT light bulb

[landyacht318]

After a prolonged absorption charge, The 12v flooded screwy31(130AH new) required 6.2 amps to nearly instantly be brought upto 16v, and this would taper to the 4.2amp range just about the time the Specific gravity maxed out.

My meanwell rsp-500-15, rated for 500 watts, is capable of over 600.

Its internal fan is LOUD.

Previous to my acquiring the Meanwell, I had the 23$ Etopxizu 30 amp power supply. It would do 38 amps with voltage cranked up into a deplted battery, but over 36 amps made a noise indicating it was not happy. It clearly lacked overamperage protections. I believe it maxed out at around 15.5v unloaded, but do not recall for sure.

There are so many similar looking power cheap power supplies on amazon and Ebay, and many will claim overcurrent and overvoltage protections, but those are just words without meaning unless verified.

If I turned the voltage down on the cheapowatt faster than the battery would naturally bleed off voltage, the etopxizu cheapowatt made a hideous whining sound. There is a long thread if one wants to search the terms Etop cheapowatt

If I do the same to my Meanwell there is an Audible click and amp output goes to zero until battery voltage falls to where i have set my dial.

I think one has to be suspicious of the ventilation and heatsinking of all these power supplies. I cut holes in my lid for 60mm intake and 80MM exhaust fans, and now the extremely loud and powerful 40MM fan only comes on over 32 amps output and when over 65F ambient temp and the highest temp I have seen on a thermocouple epoxied to an internal heatsink is 118f.

There are a few Meanwells like the SE-350 which have constant current limiting on overload, and these can be had in the 50$ range. The PS's to avoid are those with rollback or hiccup current limiting on overload.

[brulaz]

I've used a Meanwell 500W adjustable power supply for this.
It's noisy and the V setting is twitchy but it works well.
(landyacht has modified his to fix both those issues)

Higher wattage units are available.

[dclark1946]

I am looking at one of the low cost switching power supplies (0-30V, 10A with digital V and A display). I can get a 5A version locally at Frys. The 10A version I ordered from Amazon arrived yesterday but was DOA. Display showed all 0's even though both current and voltage knobs were set for max. On second turn on there was a pop and now no display. Not sure how common that is for these types of supplies.

[jkwilson]

It's going to depend on the condition of the battery and how long you want it to take. Even a couple of amps will do it given enough time. 10A should be plenty.

[pianotuna]

5 amps per 100 amp-hours of capacity is the multiplier to use.

[Artum_Snowbird]

The size of your rig would likely take a 45 amp converter. That basically means when your batteries are at there maximum potential for current input, your converter can provide 45 amps from a good 120 volt AC source to fulfill that load. The final current necessary to equalize would be a small fraction of what the converter can provide. It is more a function of the quality of converter and it's built in electronics.