What's Your Favorite Battery Charger & Maintainer?

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NCSU Dad

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OBX NC

I've used the Battery Tender brand in the past to keep boat batteries fully charged. Unfortunately they are pricey and mine seem to fizzle out and stop working after 2 years or so. I want to put one on our Class C cranking battery and was wondering if there are any favorites among the RV fellowship.


Thanks!
 
Go to Harbor Freight. For less than 20 dollars they will sell you as many as you need. Picked up 2 several years ago to to keep my Dodge Ram batteries warm all winter. Never had a problem with them. I now use one of them on my lawn tractor over the winter.
 
I'm hoping Santa brings me this. A bit more than a maintainer only, but I have several things I want to use it on throughout the year.
CTEK-40
 

I've used the Battery Tender brand in the past to keep boat batteries fully charged. Unfortunately they are pricey and mine seem to fizzle out and stop working after 2 years or so. I want to put one on our Class C cranking battery and was wondering if there are any favorites among the RV fellowship.


Thanks!

I ordered two of these to use in our diesel pickup & car.
 
I'll second the Harbor Freight. Bought 2 of them back when HF was doing coupons, got them for $5.99 each. I use one on my 1970 Mach One, and the other on my wife's Camaro when we don't drive it for extended periods. They seem to work fine. The Mustang cranked over fine after sitting for 4 months last winter.
 
What are some of the advantages of the more expensive chargers?.... I can understand getting a trusted name brand... And we all like our new toys.... But what do you get out of something, more, than the likes of something like the "Battery Tenders"?
Butch
 
A "smart charger" is well known and easily replicated technology. No trade secrets and the components are off-the-shelf stuff. It's one of the applications taught in electronics schools, so the very best usually isn't much better than the average. Are some built a bit more solidly than others? Sure, but how much more is that worth? I usually avoid the very cheapest because their workmanship may be less than good, but [IMO] the mid-priced units ought to be just fine.
 
The differences are in how the charger maintains a full battery. Some tenders just give battery a constant voltage. Advanced ones will monitor the battery and alter the voltage to optimize the state of charge and compensate for temperature.

I have a solar panel and an MPPT charge controller that analyzes the battery SOC a hundred times per second and adjust the charge output.

I used to use a simple dash board 5 or 10 watt solar panel plugged through the DC outlet for my motorhome starting battery. Park the vehicle facing south and the battery is always at full charge. On that same motorhome I had a 15 watt solar panel (20 years ago) on the roof for the coach batteries. I knew little. The solar panel put out 18 volts and I had it wired directly to the 2 marine batteries with no issues and the batteries lasted a very long time. I assume the solar panel put out such a small amount of amps that the 18 volts were not able to do harm. I still have that panel. I sold motorhome, and just have trailers now.
 
I just removed the converter in my Chinook and replaced it with an Iota 45 3stage charger. The original 1997 was bad about boiling my batteries dry. I personally like the Iota products and my batteries seem happy.
 
Go to Harbor Freight. For less than 20 dollars they will sell you as many as you need. Picked up 2 several years ago to to keep my Dodge Ram batteries warm all winter.
Unless you're a ham that is on HF. The electrical noise those HFT battery maintainers put out is ridiculous. I had them in Auburn. I had to unplug them all to get on the air. I will no longer use them.

I now generally buy the waterproof battery maintainers as I often use them outside.

-Don- ABQ, NM
 
What are some of the advantages of the more expensive chargers?....
Don't confuse chargers with battery maintainers. Chargers charge at a higher current and do not shut off & on automatically as needed as do battery maintainers.

But some reasons for the more expensive battery maintainers could include:

Waterproof for outside use.

More charging current rates for more types of batteries.

More stages of charging (different and best charge currents as the battery charges up).

-Don- ABQ, NM
 
On the little $100 maintainers it probably doesn't matter but on larger battery chargers the difference between the quality units and the CCC (cheap chinese crap) is repair-ability. The CCC stuff is just garbage when it fails but the better built stuff can be repaired. I've opened chinese chargers (Go brand IIRC) that had all of the chips painted with red epoxy so that the numbers couldn't be read and the unit couldn't be repaired. That's deliberate! the people at GO don't want their products repaired, you're supposed to be a good little consumer, present your wallet and buy a new one.

Look at Progressive Dynamics, you'll get three stage charging and intelligent maintenance over the whole winter, designed and built in the USA.
 
I've already answered all the questions in that thread. If you don't want to believe me that's up to you Don but Progressive Dyanmics is a big, popular, established business, do you really think you are right and they are lying?

Don't you think if it was just timers someone else besides you would have noticed the same thing?
 
I think you've made a mistake somewhere but it's not anyone else's job to find it.

The Charge Wizard constantly monitors battery voltage and battery usage then selects one of the following four operating modes to properly charge and maintain the battery.

BOOST Mode 14.4 Volts – Rapidly brings the RV battery up to 90% of full charge.
NORMAL Mode 13.6 Volts – Safely completes the charge.
STORAGE Mode 13.2 Volts – Maintains charge with minimal gassing or water loss.
EQUALIZATION Mode 14.4 Volts – Every 21 hours for a period of 15 minutes prevents battery stratification & sulfation – the leading cause of battery failure.
 
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A couple of weeks ago I spent 3 nights mooch docking at a friend's place. Didn't run the generator for any of those days. After 3 days without a recharge, when I plugged the coach in at Mt Laguna the converter went straight to Boost mode for a couple of hours before it dropped back to Normal.
In normal day to day operation, it seems like in the evening, when I'm running a few lights and the furnace the charger stays in the "Normal" mode. During the day, with nothing 12v running in the coach, it's indicating the "Storage" mode. That seems to be the normal pattern.
The only thing I see in the paperwork for my converter about timers is for the Equalization mode, which is supposed to operate about once a day or so for a short time.

My Interstate GC2's(1 pair)are approaching 6 years old, and I was highly surprised that I could run the coach 3 nights without the generator. Wasn't running the furnace at night, but I ran it every morning when I got up to take the chill off the coach.
 

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