Mean Well power supply for my usage

mena661 wrote:

Snowman9000 wrote:

If left on for 24 hours, would it taper amps down to next to nothing while staying at 14.8v? I don't plan to do that, but I want to understand how it behaves.

Snowman, never left mine on at 14.8V that long. I use mine as a float charger primarily and it will taper to 0 amps at 13.3-13.5V as batt SOC rises to 100%. I would think that behavior would translate to higher voltages as well.

I have let my modified pm4b-45 go for several hours, at 14.8v, on full batts. The amps go static and the volts hold firm at my set point.

Like a car. You either have control of it, or you don't (back seat driver). If I don't feel like driving I don't let a 12 year old substitute. Much like letting a "Smart Converter" do all the thinking for battery charging.

If and when someone makes a "converter" that is the equal of the 25-year-old technology of the Trace 2500SB Inverter Charger, then I'd say the industry is getting places.

1. Adjustable absorbsion voltage limit
2. Time spent at absorbsion limit
3. Float voltage control
4. Temperature compensation

Folks who are weekend warriors or suckle at power posts regularly do not need this level of battery charge control. RV's that cycle their batteries down to 70% full then recharge do not need this level of control.

And I keep in mind that a few folks would rather die than admit their method of doing things did not work out in the long run, after all. Some of the claims that I read sound like the 4 lb fish that grew to 10 lbs after a few years, and fuel economy claims that no one else on the face of the earth can equal. A person cannot help but learn to take these claims with several grains of salt.

Batteries that routinely see 50/50 cycling are in a different universe than batteries that see 30% discharges, or occasional 50% discharges. Even a week or so is not long enough to allow batteries to display their inner sometimes psychotic behavior. In short someone who routinely discharges batteries 20-30% overnight then quickly refills them the next day with generator and solar power hasn't the faintest idea of how their little monsters will react if forced into a 50/50 march for weeks at a time. More demanding yet is a 50/20 or 50/30 charge routine with occasional bouts to make up the missing 20-30% of amp hours.

At home I am mostly fortunate where I can float my 28 volt system and play with float finishing voltage. But when a storm or hurricane comes long and knocks power out for a couple of weeks, I have to change the routine totally and completely from an overnight or day long outage. Twenty-two years is a long time for a battery to last. If they had seen regular 50/50 operation I'd bet the lifespan would have been cut in half.

A Honda engine coupled to a tiny 70 amp alternator like an ND would make a formidable battery charger. Where a standard generator may struggle to power a 40 ampere charger, the 70 ampere alternator load would be a breeze. It's all about efficiency.

+111

The meanwell/megawatt is for you if you wish to take control of the charging process, or some aspect of it. Downside is, you MUST take control of it, or eventually you will do more harm than good.

There is a lot of wiggle room in charging most batteries, and most charger mfrs seem to cling to the conservative side of this wiggle room. If you know what you want and are willing to monitor the process, there is remarkable value in these chargers.

I have a lot of confidence in the Iota DLS chargers, and in my Prosine charger. I like that in both cases I can set it and forget it and the results will be just fine. But in almost every case I am charging from shore power, so I don't really care how long it takes.

I use the Meanwell when tent camping on a combo of solar and gennie power. For a variety of reasons I want to minimize the gennie time, and moreover I must fit all my charging into a 500w gennie. A commercial charger that would play nice with a 500w gennie would take days, rather than hours. I use the Meanwell to maximize the boost phase, particularly the 50/90 quick charge cycle. Later when I return I'll put my batts on a float charger and just let them soak.

I would also suggest that, depending on the size and or Group and brand of your battery, the set voltage on a MegaWatt will vary. Manually... always, and by you, depending on what you need it to do.

Group 31's and Trojan T-1275's fall into the Prom Queen /High Maintenance /unique charging voltage characteristics in battery recharging to 100% SOC, as well as equalizing.

They are designed first and foremost to fit into small, limited spaces, not designed to be the best battery they can be, like a GC-2, or L-16, where there is enough Acid to lead plate ratio to recharge relatively efficiently.

Consequently, some of us have found that these PIA models need a bit more voltage force fed to them to "git 'er done". 14.8 is fine, but some of us end up at 15.0, or 15.1 or even 15.3V, in the case of US brand batteries, on a daily basis, to even get close to 100% SOC.

YMMV, read up on others experiences here, to find out more... it really is a matter of fine tuning your routine to get the most out of your battery, per charge, and for the life of the battery. There will always be trade offs between weekend warriors, people off the grid full time, people that like it quiet without gens running, or the min run time possible, etc, etc, etc. You need to read and pick out what works best for you.

Snowman9000 wrote:

If left on for 24 hours, would it taper amps down to next to nothing while staying at 14.8v? I don't plan to do that, but I want to understand how it behaves.

Snowman, never left mine on at 14.8V that long. I use mine as a float charger primarily and it will taper to 0 amps at 13.3-13.5V as batt SOC rises to 100%. I would think that behavior would translate to higher voltages as well.

I posted three charts using my meanwell rsp-500-15 in that thread It will do nearly 41 amps until battery voltage comes within about 0.3v of the voltage setpoint I choose. Then amps taper.

Either megawatt will work fine. If you get a meanwell get one which says constant current on overload. Not hiccup mode nor anything else. The rsp series kicks burro. I love the control. The 3 stage chargers have their place and their fanboys who promote ignorance in their desire to get others to approve their purchase.

The higher the chosen voltageof the mw's the longer it remains maxed out at 40 amps

Snowman,

When Mex said... "A Mega will do fine. Set the voltage to 14.8 Two hour of "BOOST" at 14.4 will deliver around 60 to 70 amp hours. When it drops back to "NORMAL" at 13.6 the game is all over. The batteries are going to laugh at that unless you use a sundial as a timer. This is where a power supply kicks in and fills the gap at 14.8 volts"... he was indeed referring to two different units.

My apologies, I should have made the comparison between the language used for 3 stage chargers, compared with the language used to describe the workings of a psu. Keeping in mind, a 3 stage charger is a psu:

Constant current is called "Boost/Bulk/etc" mode when referring to 3 stage chargers. Likewise, constant voltage is called "Absorption/Normal/Finishing/etc" mode. But it's all the same charging sequence.

Mex said, "The object here is for the optional PS to take over when the P.O.S. OEM converter decides to lean on a shovel, right?"

I don't think mex was being literal here, but referring to replacing the CONVERTER with a CHARGER, and in this case employing a psu as your charger. Converters are great at providing 12v power to your rig for 12v lighting, etc., but the 'charger feature' that comes with these converters are generally set to too low a voltage for charging OFF GRID. Most 'boondockers', such as yourself, would prefer not to run their genset for hours on end, just to charge their batteries. And this is not an unreasonable expectation by any stretch. Moreover, it easy to achieve such a goal by simply using a charging source that can be adjusted to a more realistic voltage. A simple solution to a simple problem.

Unfortunately, truth and myth are often skewed by marketing misinformation (perhaps even dis-information?) and urban legend. The myth, in this case being, deep cycle batteries like to coddled and suckled like babies, when in fact they are hungry as hell, and need a decent meal. For example, some here will insist their Trojan T-105's "like" to be charged at 13.6v. It occurred to me that these folks must be doing some sort of Mr. Spock Mind Meld on their batteries, to acquire such intimate knowledge, when in fact Trojan, themselves, recommend a daily 14.8v charge. You will no doubt encounter folks who simply cannot let go of the myth and get a grasp on the reality that charging at higher voltages will NOT kill your flooded lead acid batteries. Yes, over charging will kill your batteries, but no one here is suggesting any such thing. In fact mex's timer suggestion is proof positive of this.

Yes you are on the right track... you want to charge your batteries within a reasonable time frame; which simply cannot be accomplished using a converter with a charge feature set to a low voltage. And yes, 14.4v will make a significant difference over 13.6v, but then again, so will 14.8v over 14.4. The example I gave comparing a 60 amper to a 40 amper was using the same 14.8v setting. But try using that 40 amper at 14.4v boost/cc, followed by 13.6v abs/cv, and watch your charge time rise to closer to 8-10 hours.

Hope this helps to clarify things.

Yeah! listen to the pontifications of the king of 99 cent voltmeters. He'll learn ya, in a jiffy!

I misunderstood your situation, I guess "I be behind".

A charging source using 13.6 volts is going to have very limited amperage output. The Mega most assuredly will put out 40 amperes charge rate right off the bat. No contest.

Niner quote:xxxxxxxxxxx


150 AH ?? Mouse nuts (in your own words) Peanuts (in mine)
I have 230 AHs in my 2 27s

What was wrong w/ your 9245 ?
Mine works fabulously.
You better quit worshiping Mex, you be far ahead.