Manual Battery Charger

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LostOhSoLost

10 posts

Wannabe Geek

#315292 30-Jun-2024 14:30

My old manual battery charger for 12 volt lead acid has died (well actually won't go above 12V as a charge voltage).

While I have a multistage charger, the manual one is handy at times, & I just don't seem to be able to find a non automatic charger (well without speeding $500 or so on an all singing and dancing model).

Does anyone know is there anyone who sells a manual battery charger or am I going to have to get this one repaired (its only a 13 year old repco unit so nothing special).

RunningMan

8953 posts

Uber Geek

#3254742 30-Jun-2024 15:08

https://www.jaycar.co.nz/12v-1a-sla-battery-charger/p/MB3619

tweake

2391 posts

Uber Geek

#3254757 30-Jun-2024 15:21

if its an old school manual one then it sounds like its blown a diode. should be easy enough to fix.

just having bought a new replacement, old school models are pretty much history with all the different battery types around now.

tweake

2391 posts

Uber Geek

#3254761 30-Jun-2024 15:24

RunningMan:

https://www.jaycar.co.nz/12v-1a-sla-battery-charger/p/MB3619

you would be there all week waiting for that to charge a flat battery up. in fact one problem i have come across is you need to match the battery charger to the size of the battery. many modern chargers do not like being put on bigger batteries that they are intended for.

johno1234

2793 posts

Uber Geek

#3254770 30-Jun-2024 15:46

tweake:

RunningMan:

https://www.jaycar.co.nz/12v-1a-sla-battery-charger/p/MB3619

you would be there all week waiting for that to charge a flat battery up. in fact one problem i have come across is you need to match the battery charger to the size of the battery. many modern chargers do not like being put on bigger batteries that they are intended for.

I know the OP doesn't want a smart charger but.. I have two CTEK units, a little 0.8A one that sits on the JetSki over winter to maintain the battery. Cost about $120 from memory. It theoretically could charge a car battery but it would take a long time. I have another grunty 10A one found 2nd hand off TM for a couple of hundy. That one that according to the manual can safely charge batteries from 20Ah to 300Ah. In other words anything from a motorcycle to truck battery. Must know not to pump 10A into little batteries.

All I can say is they are fantastic units. I've brought horribly abused batteries back to life with these things and the ability to maintain the battery is essential for boats and jetskis.

[ADD] also the CTEK units can be told to be dumb and just sit there and pump out 13.6V at up to 10A forever. Useful if you just want a power supply for something.

tweake

2391 posts

Uber Geek

#3254784 30-Jun-2024 16:11

johno1234:

I know the OP doesn't want a smart charger but.. I have two CTEK units, a little 0.8A one that sits on the JetSki over winter to maintain the battery. Cost about $120 from memory. It theoretically could charge a car battery but it would take a long time. I have another grunty 10A one found 2nd hand off TM for a couple of hundy. That one that according to the manual can safely charge batteries from 20Ah to 300Ah. In other words anything from a motorcycle to truck battery. Must know not to pump 10A into little batteries.

All I can say is they are fantastic units. I've brought horribly abused batteries back to life with these things and the ability to maintain the battery is essential for boats and jetskis.

[ADD] also the CTEK units can be told to be dumb and just sit there and pump out 13.6V at up to 10A forever. Useful if you just want a power supply for something.

ctek might be better (but they are also $$$) but if you put a charger thats meant for 100ah on a 300ah battery, some will just come up with "faulty battery" and stop charging. the battery is dragging the voltage down to much so it thinks its a shorted battery. the old school ones will just let voltage go down as they have no detection circuits, a bigger battery means longer charging time.

i would really like to get a selectable amp output model one day. much better when you have trucks, utes, bikes etc.

RunningMan

8953 posts

Uber Geek

#3254796 30-Jun-2024 16:31

tweake:

RunningMan:

https://www.jaycar.co.nz/12v-1a-sla-battery-charger/p/MB3619

you would be there all week waiting for that to charge a flat battery up.

That would depend entirely on the battery capacity, which we don't yet know. It may or may not be an issue anyway.

johno1234

2793 posts

Uber Geek

#3254797 30-Jun-2024 16:33

tweake:

johno1234:

I know the OP doesn't want a smart charger but.. I have two CTEK units, a little 0.8A one that sits on the JetSki over winter to maintain the battery. Cost about $120 from memory. It theoretically could charge a car battery but it would take a long time. I have another grunty 10A one found 2nd hand off TM for a couple of hundy. That one that according to the manual can safely charge batteries from 20Ah to 300Ah. In other words anything from a motorcycle to truck battery. Must know not to pump 10A into little batteries.

All I can say is they are fantastic units. I've brought horribly abused batteries back to life with these things and the ability to maintain the battery is essential for boats and jetskis.

[ADD] also the CTEK units can be told to be dumb and just sit there and pump out 13.6V at up to 10A forever. Useful if you just want a power supply for something.

ctek might be better (but they are also $$$) but if you put a charger thats meant for 100ah on a 300ah battery, some will just come up with "faulty battery" and stop charging. the battery is dragging the voltage down to much so it thinks its a shorted battery. the old school ones will just let voltage go down as they have no detection circuits, a bigger battery means longer charging time.

i would really like to get a selectable amp output model one day. much better when you have trucks, utes, bikes etc.

The CTEK ones have the dumb mode override to just keep it going despite the faulty battery alert.

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pih

649 posts

Ultimate Geek

Lifetime subscriber

#3254812 30-Jun-2024 17:18

If you want a bit more control you could look at a low cost benchtop power supply with constant current / constant voltage limits set. Look up your battery chemistry and capacity online for ideal charge rates and maximum voltage and current and let it take care of the rest. You don't get the benefit of desulphation / repair that many multistage chargers provide, but it's a handy multipurpose tool to have around.

tweake

2391 posts

Uber Geek

#3254863 30-Jun-2024 17:24

johno1234:

The CTEK ones have the dumb mode override to just keep it going despite the faulty battery alert.

kinda ruins the whole point of spending quite a bit on an auto charger if you have to run it on manual. especially if you have to then change it back to finish charging (some battery types require higher). i have done that before, used old dumb charger to get it half way there and then use the auto charger to finish charging.

tweake

2391 posts

Uber Geek

#3254865 30-Jun-2024 17:31

pih:

If you want a bit more control you could look at a low cost benchtop power supply with constant current / constant voltage limits set. Look up your battery chemistry and capacity online for ideal charge rates and maximum voltage and current and let it take care of the rest. You don't get the benefit of desulphation / repair that many multistage chargers provide, but it's a handy multipurpose tool to have around.

the problem i see with that is you can't just leave it to do the rest. you really have to know what your doing and most people would screw it up.

one of the common problems is that most people get calcium batteries as replacements (try finding a normal battery theses days). they require 15v or so for a period of time. this is where i suspect an old school charger would work well, if you use a timer with it.

things like gel cells, maintenance free, agm, elb batteries all throw a curve ball into the mix.

johno1234

2793 posts

Uber Geek

#3254907 30-Jun-2024 18:58

tweake:
kinda ruins the whole point of spending quite a bit on an auto charger if you have to run it on manual.

Not at all. It means you can get away with one charger instead of two.

ajw

1932 posts

Uber Geek

#3256237 4-Jul-2024 13:35

Minimum six amp.

https://www.trademe.co.nz/a/motors/car-parts-accessories/search?search_string=battery%20chargers