Recommend a Charger for very small system...

[Murby]

Hi Folks,
I'm purchasing two trojan T-105 RE batteries that are 6 volts and 225AH (20hr) each.. Going to wire them in series.
They will be charged with normal household current but I need someone to recommend a good little and semi-cheap charger.

I bought these batteries for a specific purpose.. 1) to keep my 12 volt sump pump running when the normal grid power is down, and 2) to keep my 40 watt blower motor (110 volts) running on my wood stove. I will use a small 400 watt cheap-o inverter that works great for the purpose.

Can you folks recommend a battery charger that will keep my batteries in good condition for the 99.9% of the time I never use them? And something that can charge them back up in a reasonable amount of time when I start the generator for several hours each day? I'm not looking for a Ferrari here but don't want to put my investment in the hands of a harbor freight piece of junk either.

One other unrelated question.. What's a good price to pay for the T-105 RE battery?

Thanks!

[Mike90250]

First, I don't think you need the RE version. Simple cheap golf cart versions would do just as well.

For a decent charger that will keep the batteries on FLOAT charge, and be able to recharge when the power comes back, I would suggest the NOCO 15A
https://no.co/g15000 unlike many chargers, it retains the battery settings (at least my 5A one does) through a blackout and restarts when power is applied
Smaller ones will work to keep it on float, but would take a long long time to recharge after heavy usage.

[Murby]

$200 is a lot of money for a battery charger.. is it really necessary?

[Laspher]

For costly batteries, I would say yes. I would want to protect that kind of investment. $400+ in batteries would be worth at least a $100 charger, $200 if it guarantees a long (if properly maintained) life for the batteries you need in an emergency.

[Mike90250]

$200 is a lot of money for a battery charger.. is it really necessary?

Of course not. Harbor Freight sells chargers and something in the 15A range would work. It might boil the batteries dry in 4 months, or it might stop working, but it's only $40 and your basement flooding,

The Noco charger is a smart charger, it drops back to a lower float voltage after completing the charge cycle. Cheap automotive chargers have one voltage and are mean to be removed after a day.

[Murby]

Thank you for the advice.. Sorry but I had something come up and forgot to come back to say thank you...

[Sunking]

$200 is a lot of money for a battery charger.. is it really necessary?

No you are just looking in the wrong places If you want a decent 3-Stage charger does around $40 sound better? Look up a Schumacher XCS15 or Schumacher SSC-1500 Ship-N-Shore.

[Murby]

So what's the difference between the $40 or $50 Schumacher and the $200 chargers that were recommended? I mean, there must be some reason why folks buy the $200 unit instead of the $40 unit if they do the same job right? Where's the difference and why is it important?

[Laspher]

TESTING
I replied to Sunking but my post didn't show up.

Probably an issue with links in the post, or reply, it has gotten my a couple of times. Admin has to approve posts with more than one link.

[Sunking]

So what's the difference between the $40 or $50 Schumacher and the $200 chargers that were recommended?

If you are referring to the one Mike linked to is the NOCO has more Bells and Whistles. Example it is made for 12 or 24 volt battery, settings for Lithium and Lead Acid, a worthless desulfator, and battery diagnostics.

They both do the exact same basic function of 15-amp 3-Stage charging.

[Mike90250]

Thanks Sunking, I was not aware of the Ship-N-Shore line of chargers, they look fine to me, if they throttle back and do long term float voltage. The Noco lists the voltages it runs/falls back to.

[Sunking]

Thanks Sunking, I was not aware of the Ship-N-Shore line of chargers, they look fine to me, if they throttle back and do long term float voltage. The Noco lists the voltages it runs/falls back to.

No problem Mike. Only reason I know about them is where I live now lot's of people have boats so I get to play with Marine stuff. Some of it is good, some of it junk.

I knew from the OP application he is really looking for a FLOAT CHARGER, and will not be cycling batteries. 3-stage is more than he really needs. All he really needs is a 15 to 25 amp Float Charger or DC Power Supply with an adjustable voltage. and current limit. Something like Ham Radio Operators use.

I have given some serious thought to making and selling 12 volt switching DC Power Supplies that also charge batteries. A cheap no thrills model. But there is no real money in it and very time consuming.

[PNjunction]

UM, the Schumacher chargers may surprise you when you actually test the terminal voltages of the batteries differing greatly from the voltage stated on the display. I have reviewed and commented on them a few years back.

They are intended for hammering dead sulfated garage-queens and abused AUTO batteries back into shape to get your vehicle moving - aka speedcharge. But for *normal* maintenance? Your Fluke will tell you NO-WAY if you take the time to chart/measure the entire algo *at the terminals* as I did.

So too, the Noco - differing algorithms depending on what year you purchase it in - despite the same model nomenclature. Some will allow your battery to just self-discharge to a low voltage before triggering the recharge. Assume here that this would be relatively quick if you have an automotove parasitic load. Ok, great. BUT for a non-automotive environment with no parasitic load, that just walks down your capacity. I've been there and done all that!

Hence my advice NOT to use automotive-type chargers you find off the rack for any non-automotive use - except for one.

Over the years, if I had to pick ONE for general maintenance these days, it would be the Tecmate-Optimate 6 or now the 7 (10A) as being the smartest and *safest* for us propeller heads, and also grandma. The new models have a smart-switchable setting for 14.7v absorb for those who have high-performance agm's that want to see 14.7 instead of the standard 14.4v. FLOAT, if the battery passes testing, will be a 50/50 duty cycle of 13.6v in 30 minute intervals.

Note for the new 14.4/14.7v switchable new models - there is no mechanical switch to wear out, just a capacitive touch button, so the unit is always sealed. To make the switch to 14.7v (like for Optima and Odysseys), just plug in the unit, hold your finger down for about EIGHT seconds, and the unit will switch over and the led will change. It will remember this setting from now on. To switch back to 14.4v, say for most flooded or *conventional* agm's, repeat the procedure and it will dutifully remember that as the default. This was something I asked for a few years back and got it! Older units are great too, but the new ones are even smarter.

[PNjunction]

Completing the process for agm's!

Most consumers don't know or care that agm's like to be treated to an "extended absorb" of about 14.4v for about 24 hours when initially received, or perhaps on 6 months intervals while in storage. Nevermind the fact that most chargers won't do this (or will do a short 3-hour run of 15v every 30 days or so, aka the Optima charger). WARNING - we're talking CC/CV here, NOT constant-current trickle charging.

See the C&D technical manuals for commercial information about this that consumers don't usually get or know about.

Thing is - what if you are happy with your existing setup, but don't have the time or inclination to drag out a lab-power supply to hold at 14.4v for 24-48 hours?

The Xtreme-charge XC100-P will do that. It is a 2.5A charger, but will *eventually* end up doing the extended absorb, smartly, well after the 100% charge indicator has gone out. I personally don't leave my battery on it 24/7, but to perform this extended absorb for a few days (it takes awhile to get there) - it is the only consumer charger I've seen that will do that - safely.

Ignore all the desulfation stuff if you want to. Talked about in other threads so no need to rehash it here. But from a strict charging standpoint - it is the only one, aside from dragging out your own lab power supply that will do this - eventually. Makes for a great follow-up to other chargers for us agm guys that REALLY get into it.

[PNjunction]

And to prove I'm not a corporate shill, for your maintenance application, the Tecmate-Optimate 7 is one of the very few "automotive" type chargers I'd trust with my expensive batteries. Especially now the "select" models which allow for 14.4 / 14.7v options. Just as important, does FLOAT the right way, be it a vehicular or stationary battery.

The red-flag I forgot to mention is the desire to cheap out. Disaster awaits your expensive batteries with that mindset. Same thing for solar which junky little solar controllers.

I just laugh when I see a guy spend $1K on his batteries, and then cheap out on the back end with charger / controller junk and come crying a few months later.