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Zippaboy

Is our car's alternator a smart-charger? or constant load?

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for my cars usually when it is time for a change of batt, i will change to an oversized one.

because my cars are usually underutilized and i ever been overseas for up to 2 mths.

 

after 2 months, the car still start up fine !!!!

 

One of the mechanic ever told me before, that the car's alternator is not a "smart" charger.

there is no tickle-charge when the batt is almost full or it doesn't stop charging even when it is full.

the load on the alternator is constant.

 

 

anybody knows or can share his knowledge on this topic?

 

 

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for my cars usually when it is time for a change of batt, i will change to an oversized one.

because my cars are usually underutilized and i ever been overseas for up to 2 mths.

 

after 2 months, the car still start up fine !!!!

 

One of the mechanic ever told me before, that the car's alternator is not a "smart" charger.

there is no tickle-charge when the batt is almost full or it doesn't stop charging even when it is full.

the load on the alternator is constant.

 

 

anybody knows or can share his knowledge on this topic?

 

Hamsup thread spotted!

Edited by I_RIDE_DEEP

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Hamsup thread spotted!

 

Tikko :wub:

 

My tyre and batt man also mention that but he say the main thing for bigger battery is more stable for A/c load and all the ele we have on board drawing current.

 

Abt TS pt the car can start 2 mth after holiday, I don't think is a battery thing but more of your car electronic device don't draw electricity when it is not locked.

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For cars with smart charging system, the monitoring of amp output depends on the load demand which is controlled via the on-board computer and do not have any correlation with engine speed. That is the advantage of such new innovative system which normally come with calcuim battery.

For conventional 12volt car lead acid battery system, the alternator charging will only happen when the engine speed is above 2,000rpm - the output will first supply the need of the engine systems and elect acc and the excess is pump into the battery for storage.

The alternator amp max output is controlled by the diode rectifier unit and the battery system pressure -voltage.

Generally, if the battery is 100% charge , the alternator will still continue to generate amp to feed the ignition system and other electrical acc ( so long as the engine speed is above 2,000rpm ).

Hope this helps

 

PS Parasite amp drain - the rule of thumb is generally about 20mili amp and not more than 30mili amp ( depending on the amp hr of the car battery being used). The battery can be easily maintain if you plug in a solar powered battery charger of 2 to 4 watt capacity.

post-272-1364692696_thumb.jpg

Edited by Yeobh

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Actually the reason why I asked is because there is another group of believers. Who feel that we should not oversized the battery.

 

Bigger battery= longer time to charge = overall

More load on the stock alternators.

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Actually the reason why I asked is because there is another group of believers. Who feel that we should not oversized the battery.

 

Bigger battery= longer time to charge = overall

More load on the stock alternators.

 

Just stick to manufacturer's specs. You can't go wrong with that normally.

 

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Oversizing is ok so long it is not overdone - normally up by max 20%. Alternator is a "pump" - if the alternator max amp output is 60amp and if it runs for 80% of the time at max output ,chance the alternator will have very short life.For illustration -if you have a 300amp battery ( large pond) and use a 30amp small alternator ( small water pump ), the small pump can still do the work but the time taken will be very long and the alternator will be overworked and logically heat up fast.

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Oversizing is ok so long it is not overdone - normally up by max 20%. Alternator is a "pump" - if the alternator max amp output is 60amp and if it runs for 80% of the time at max output ,chance the alternator will have very short life.For illustration -if you have a 300amp battery ( large pond) and use a 30amp small alternator ( small water pump ), the small pump can still do the work but the time taken will be very long and the alternator will be overworked and logically heat up fast.

 

Yeo, my car battery is only 45Ah which is stock specification but when i got someone to step on the gas till about 4000rpm, the output voltage across the battery was only barely touching 14V. is that a problem with that kind of low charging voltage considering we need to charge the battery till 12.66V?

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Just stick to manufacturer's specs. You can't go wrong with that normally.

 

 

I could stick to the manufacturer's specs and change a brand new batt every 6 mths.

The batt performance drops tremendously once it drop past a certain level, or when it is fully drained.

 

 

I am asking, because of my special needs that the car can be dormant for 2 mths.

Edited by Zippaboy

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Oversizing is ok so long it is not overdone - normally up by max 20%. Alternator is a "pump" - if the alternator max amp output is 60amp and if it runs for 80% of the time at max output ,chance the alternator will have very short life.For illustration -if you have a 300amp battery ( large pond) and use a 30amp small alternator ( small water pump ), the small pump can still do the work but the time taken will be very long and the alternator will be overworked and logically heat up fast.

 

 

That is the thing. Is the alternator smart enough to "pump" accordingly to the load required?

 

Or it is just constantly "pumping" the same amt even when batt is full?

 

 

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When charging the input voltage will have to be higher then the battery voltage, without the higher pressure there is no way to get EMF into the battery plates. 14 volt is already high, most of the battery charger will float at 13.8volt. Battery without load - 12.8 is consider good. If after a good charge and the battery still remain at 12.45 which is about 75% charge., either the battery is sulphated or is getting old. Time to look for a new replacement.

The best way to check the battery health is by using a hydrometer, the diluted sulphric acid specific gravity give you the most accurate indication of yr battery health.

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Yeo, my car battery is only 45Ah which is stock specification but when i got someone to step on the gas till about 4000rpm, the output voltage across the battery was only barely touching 14V. is that a problem with that kind of low charging voltage considering we need to charge the battery till 12.66V?

 

After I upsized my battery, I had a voltmeter plugged in.

 

When charging, it is around 13.8v-14.2v

 

When I turned on the car before cranking, 12.8v-12.9v

 

 

 

 

 

 

 

 

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No it will vary via the alternator diode amp regulator unit.

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No it will vary via the alternator diode amp regulator unit.

 

Ok thanks!!

 

I understand that for example our headlights, it draws power from the alternator.

 

Whereas the alternator push at a higher voltage to the battery.

 

Am I right to say that if I off my headlights/foglights/amplifiers/sound systems, the battery will charge faster and there is lesser load on the alternator?

 

Thanks once again.

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For cars with smart charging system, the monitoring of amp output depends on the load demand which is controlled via the on-board computer and do not have any correlation with engine speed. That is the advantage of such new innovative system which normally come with calcuim battery.

For conventional 12volt car lead acid battery system, the alternator charging will only happen when the engine speed is above 2,000rpm - the output will first supply the need of the engine systems and elect acc and the excess is pump into the battery for storage.

The alternator amp max output is controlled by the diode rectifier unit and the battery system pressure -voltage.

Generally, if the battery is 100% charge , the alternator will still continue to generate amp to feed the ignition system and other electrical acc ( so long as the engine speed is above 2,000rpm ).

Hope this helps

 

PS Parasite amp drain - the rule of thumb is generally about 20mili amp and not more than 30mili amp ( depending on the amp hr of the car battery being used). The battery can be easily maintain if you plug in a solar powered battery charger of 2 to 4 watt capacity.

 

Wow bro, you are the battery man. so regarding TS question, is there any advantage for installing a slightly bigger capacity battery?

 

one thing i found out was that the audio system sounds alot better when i change a new batt. so does slightly larger battery helps?

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Please read what I have written in reply to TS and others. Let me know what is your conclusion :D

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You can monitor yr alternator output by installing a aftermarket volt & amp meter

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For cars with smart charging system, the monitoring of amp output depends on the load demand which is controlled via the on-board computer and do not have any correlation with engine speed. That is the advantage of such new innovative system which normally come with calcuim battery.

For conventional 12volt car lead acid battery system, the alternator charging will only happen when the engine speed is above 2,000rpm - the output will first supply the need of the engine systems and elect acc and the excess is pump into the battery for storage.

The alternator amp max output is controlled by the diode rectifier unit and the battery system pressure -voltage.

Generally, if the battery is 100% charge , the alternator will still continue to generate amp to feed the ignition system and other electrical acc ( so long as the engine speed is above 2,000rpm ).

Hope this helps

 

PS Parasite amp drain - the rule of thumb is generally about 20mili amp and not more than 30mili amp ( depending on the amp hr of the car battery being used). The battery can be easily maintain if you plug in a solar powered battery charger of 2 to 4 watt capacity.

where can i get this bro?

 

lidat means i gotta connect croc clip to batt terminals when car locked since cigar socket isolated. cable long enuf to go into car cabin so i can place solar panel on dashboard?

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cable = 1.2m Just PM u

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