My old battery charger

That era of charger is usually only automatic in as far as the output voltage is limited to something in the region of 14.5 volts which is safe enough for short term charging. I would use it without concern but monitor the charging voltage with a digital meter until I was happy it's not excessive. I wouldn't use it as a permanently connected float charger even if I thought it safe because that type of mains frequency transformer is inefficient at very low currents due to the transformer losses. Any physically large charger is a poor choice for float charging in terms of efficiency.
 
It sounds like I should buy a modern trickle charger/maintainer for maintaining my flooded battery in 97 Buick. I'll probably get a BatteryMinder, unless there's something better.

However, would my old Schumacker set on 2A boil a G34 flooded battery if only left hooked up each week for 24 hrs?

Ctek, Optimate, are my go to brands. I have over a dozen optimate 6"s

I would trust Battery Minder, but prefer the other two.

Noco seems to be having quality issues.
 
It sounds like I should buy a modern trickle charger/maintainer for maintaining my flooded battery in 97 Buick. I'll probably get a BatteryMinder, unless there's something better.

However, would my old Schumacker set on 2A boil a G34 flooded battery if only left hooked up each week for 24 hrs?
Yes, it will boil the electrolyte in my experience, and did so on the 2 amp setting...not sure why I am repeating myself here, I said it in my previous post.

Its not "smart", it tapers but never shuts off, thus it will overcharge your battery....how much depends on its state of charge at the start and how long you leave it on. So if it is pretty close to charge and you leave it on for "only 24 hours"....you could be overcharging it for 20 hours or more. Personally, I would never leave this on for more than a few hours at a time, and use it for the occasional emergency jump start.

Get a modern battery tender like the Battery Minder 2012 or better yet the more versatile 128CEC2.
Shop around and buy it online, not directly from Battery Minder and you can save a few dollars.
 
Yes, it will boil the electrolyte in my experience, and did so on the 2 amp setting...not sure why I am repeating myself here, I said it in my previous post.
I recall you said in your previous post that your electrolyte boiled after 48 hrs on 2A charge. So then I asked about 24 hrs on 2A charge. The owners manual says it tapers down to 1A. I'm surprised 1A could boil a G34 battery, but I'll take your word on it.
Its not "smart", it tapers but never shuts off, thus it will overcharge your battery....how much depends on its state of charge at the start and how long you leave it on. So if it is pretty close to charge and you leave it on for "only 24 hours"....you could be overcharging it for 20 hours or more. Personally, I would never leave this on for more than a few hours at a time, and use it for the occasional emergency jump start.
Your explanation above provides the clarification I was asking for with regard to a 24 hr charge. Thanks.
Get a modern battery tender like the Battery Minder 2012 or better yet the more versatile 128CEC2.
Shop around and buy it online, not directly from Battery Minder and you can save a few dollars.
I ordered a BatteryMinder charger. Thanks
 
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The buzzing noise is the transformer inside, you will get that from a lot of electronic equipment. The ammeter on front should show what's flowing through the alligator clips to the battery.

Your post remains mysterious, "I bought a new battery" isn't reason alone to buy a charger... your later posts indicate you want to "maintain" the battery, perhaps on an infrequently driven car.
I bought a new wet flooded battery for a 97 Buick that is seldom driven. I want to take good care of it by using a charger/maintainter on it. I don't mind putting the charger/maintainer on it once a week and then removing it the next day. I also wouldn't mind just leaving it hooked up if that was acceptable.

I was unsure if my old Schumacher charger set on 2A would be acceptable for that purpose. It claims to be an automatic/smart charger, but I think it's really a semi-auto.

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My Schauer is a LOT older than that-it is only a 6A one, that starts at 6 & gradually tapers to around 2, too high to run continuously. I just picked up a NOCO Genius 1 (amp) that can do standard flooded or AGM & can desulphate too, & is small enough to leave on a battery all the time without boiling out the electrolyte.
I have a very similar one, like from the 70's, and it is my go-to for the older stuff which all now have AGM's. It has never let me down, but I don't use it as a maintainer, and it has an off switch unlike my more modern 'smart' one. At the risk of sounding old, they don't seem to make 'em like that anymore....at least at the consumer level :)
 
I have a very similar one, like from the 70's, and it is my go-to for the older stuff which all now have AGM's. It has never let me down, but I don't use it as a maintainer, and it has an off switch unlike my more modern 'smart' one. At the risk of sounding old, they don't seem to make 'em like that anymore....at least at the consumer level :)
They are still around. I have one of these, though I got it over 15 years ago, private labeled from Griots Garage (Griots doesn't sell them anymore) https://www.centurytool.net/K3153_1_Century_15_2_100_Amp_6_12_Volt_Charger_p/k3153-1.htm

And there are companies making versions that are microprocessor controlled so you can safely leave them connected for weeks or months if you want. Associated Equipment and Schumacher make them now.
 
I prefer BatteryMinder and the better ones have high and low temp compensation. If you charge in basement probably not needed. But outside or unheated garage, hot summer or cold winter then temp compensation can prevent overcharging or undercharging.

I have three BatteryMinders.
 
I prefer BatteryMinder and the better ones have high and low temp compensation. If you charge in basement probably not needed. But outside or unheated garage, hot summer or cold winter then temp compensation can prevent overcharging or undercharging.

I have three BatteryMinders.
Make that four in my case /
Always good to have a spare.... ;)
 
The reason these can’t be used as a maintainer is that they claim 13V-15V or so but it’s not smooth DC. It is rectified AC which is a bumpy wave with peaks around 17.7 volts or so. Averaged out, it would look at 13V at 2 amps, but in truth it reaches much higher 60 times per second, which is why it’s capable of slowly drying out the battery.
 
I prefer BatteryMinder and the better ones have high and low temp compensation. If you charge in basement probably not needed. But outside or unheated garage, hot summer or cold winter then temp compensation can prevent overcharging or undercharging.

I have three BatteryMinders.
I have three as well. I have others too, but the Battery Minder are my preference now.
 
To the OP, you Schumacher looks like it's a dumb charger and does not put out high desulfating spike voltages. So safe, no need to remove battery cable from the car when in use. Still useful, esp for topping up purposes. But it will 0vercharge any battery if left on for long enough. I'd just keep monitoring the battery it's connected to, and stop when batt voltage reaches 13.7 volts.
 
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