Benefits of old-school manual charger

[spavel6]

I have always used automatic chargers, Schumacher 2/4/6A Chargers, as well as the BatteryMINDers 12106 and 1500. I recently came across an older manual charger, a Schumacher SE-1010-2.

I've heard positive things about the manual chargers.. But what are the pros/cons of those vs the newer style automatic chargers?

 

[ragtoplvr]

Pro You can charge a dead battery that the automatic will not let you charge

You can over charge, reverse charge, under charge, not charge if your line mains are low (common around the lake and camping grounds.

Rod

 

[samven]

They had 2 types, one was a truly manual charger, nothing more than a transformer and voltage rectifier with a current meter and maybe a voltage selector for 6v. You could do anything you wanted with them. Guys made electroplater power supplies from them, they were great for the lead acid batteries you could fill but you had to be careful because they will cook your battery, the 2nd called automatic at the time had Normal and Deep cycle modes and different current selections and some had a light to indicate when the charge was done and maybe reverse polarity. But they were just manual chargers with a few big resistors a couple diodes and extra taps on the transformer. But they would shut off when they dropped below a set current level unlike the fully manual. Either one would charge a battery that todays smart charger wont even attempt to charge but the manual was better for the Hail Mary charges where the battery had sat dead for months or years and the internal resistance had gotten high enough that would cause the automatic to shut off. The great thing about them was that if you kept them inside they would last for decades. I have a manual that is 50 years old and an Automatic thats around 45 years old. I had to replace the battery clips on the manual but it still works like the day I bought it.

 

[Donald]

With a really dead battery a smart charger may not charge it and give up. So I hit it for a few hours with manual charger and then switch to smart charger.

 

[circuitsmith]

One way to use a manual charger long term without cooking a battery is to hook it to a household timer and operate it intermittently, like one hour per day.

 

[wdn]

I just got the Noco Genius 5 charger and it it will automatically charge a dead battery that is as low as 1 volt. It also has a force option that will charge a battery that is 0 Volts for ten minutes then shut off. I got the regular mode to charge a lawn mower battery that was left outside for a winter and was 1.05 volt and it charged it up to 11.93 volts. Then it concluded the battery is no good and shut off and the NG light came on.

 

[Donald]

Of course with a really dead battery and manual charger you may still end up with a battery only good as a core.

 

[Job]

I have an old Wards manual charger and a more recent Craftsman automatic. The automatic charges dead batteries the same the only thing it does different is taper off and end the charge. Maybe the old one tapered too don't remember, but think it did. Just didn't turn off and on like the auto..

 

[GMBoy]

You really need a good automatic and a manual charger in your tool arsenal. I have to often pull my manual Sears unit out to get a near dead battery charged enough to allow te fully auto charger to even start to charge a battery.

 

[ironman_gq]

Having a manual charger is a great thing. I have had to "force" a smart charger to charge a dead battery before. It involves having a second 12v battery on hand, you hook the good battery in parallel with the dead battery and then connect the charger. Basically the good battery will serve as an intermediate charger for the dead battery until the voltages balance out.

 

[brianl703]

I don't have a manual charger, but I do have a 10 amp, 30V, 300 watt bench power supply with adjustable voltage and current limiting.

I've used it to get enough charge into a dead car battery that I can use an automatic charger to finish the job.

 

[circuitsmith]

I do have a 10 amp, 30V, 300 watt bench power supply with adjustable voltage and current limiting.

That's the best thing to have complete control.
But, like with a manual transmission, you must know what you're doing.

 

[Silver]

I've been in a bind several times when my automatic charger would not charge a near completely dead battery. If the voltage drops below 6, it thinks it's a 6 volt battery. I had AAA in MY OWN F*CKIN' GARAGE ONCE because I had no feasible way to charge a battery.

I gave the last manual charger I had to my dad. I guess it's better that he have it than I, but I have since not been able to find another one. It's hard to find one, even used.

 

[bunnspecial]

I wish I had a manual car battery charger.

I have a Tektronix 30V 4A bench PSU that can operate in either constant voltage, constant current, voltage limiting, or current limiting mode. I've managed to bring some smaller batteries back to life with that.

TBH, I'd consider a similar but higher capacity bench PSU to be far superior to a good old fashioned manual lead acid battery charger. They give you a ridiculous amount of control over what you're delivering. They can cook things connected to them easily if you're not careful, but when charging batteries judicious use of one of the delivery modes can function like a pseudo-smart charger that requires occasional manual tweaking. By holding voltage, for example, constant you can get some idea of what's happening in the battery(if anything) by watching how the current changes.

One of the big benefits of a PSU like this is-again used carefully-you can "jump start" a reluctant to start battery. Provided that you know the charging specs, it's in effect a universal charger for most any battery chemistry outside Li-Ion.

 

[wpod]

When fixing fork lifts many times a user would run the battery dead which is really bad, and the automatic charger wouldn't charge the dead battery. We would pickup the forklift and jump a charged battery to the dead battery then hook up the Automatic charger and then the charger would start charging.

 

[SubLGT]

I have a Tektronix 30V 4A bench PSU that can operate in either constant voltage, constant current, voltage limiting, or current limiting mode. I've managed to bring some smaller batteries back to life with that........ By holding voltage, for example, constant you can get some idea of what's happening in the battery(if anything) by watching how the current changes.

When using your PSU in constant voltage mode to charge a battery, do you also set a current limit?

 

[BeerCan]

You should not have to set a value in cv mode for current, the battery will take what it wants, which is usually a high amount if the battery is low SOC. CV mode is usually not very good for battery life because of this, high current at low SOC usually ages batteries faster. CC is a better mode as long as you keep the C rate reasonable. You can also age the battery faster with to high of a current but if you keep it .5c or less you are usually safe. If you have a programmable PS you can do a CC-CV charge, using a low CC stage in the beginning and then switching to CV to finish it up. The trick is finding when to switch from CC to CV. Finally you can do MCC where you vary the current as the battery charges, takes a little longer but its better for the battery longevity.

 

[SubLGT]

I don't have a manual charger, but I do have a 10 amp, 30V, 300 watt bench power supply with adjustable voltage and current limiting.

I've used it to get enough charge into a dead car battery that I can use an automatic charger to finish the job.

I have an inexpensive 10A 30V power supply that I sometimes use for battery charging. But I learned a lesson a few days ago. I was not paying full 100% attention to what I was doing, and hooked up a 20Ah battery in reverse polarity. My power supply was instantly damaged. Some smoke, but no fire. Live and learn.

 

[Dave9]

^ With such a huge voltage margin, you could have put a diode in series to provide reverse polarity protection. It'll need a heatsink.

One benefit to a manual charger is, it will likely still be working 20+ years from now... +/- depending on frequency of use and temperature, plus much simpler to repair the fewer things there are to fail. This assumes the old school well built designs, not some modern junk from China.

 

[brianl703]

I have an inexpensive 10A 30V power supply that I sometimes use for battery charging. But I learned a lesson a few days ago. I was not paying full 100% attention to what I was doing, and hooked up a 20Ah battery in reverse polarity. My power supply was instantly damaged. Some smoke, but no fire. Live and learn.

Take it apart and check for a shorted reverse-biased diode connected across the output.

Remove this diode and replace. It's probably a 1N5408.

Power supply will probably work just fine.