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Default Lead acid battery charger (or alternator) switching to trickle withload present?

How does a lead acid battery charger (or car alternator) know when to switch to trickle charge? I can understand it noticing a drop in charging current if the battery is on its own, but what if a random changing load is connected, as there is in a running car?
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On 2019-06-21 1:19 p.m., Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?* I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


the catalytic converter tells it
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Default CAUTION!!! Birdbrain, the Abnormal Pathological Attention Whore, Strikes, AGAIN!

On Fri, 21 Jun 2019 21:19:05 +0100, Birdbrain Macaw (aka "Commander Kinsey",
"James Wilkinson", "Steven ******","Bruce Farquar", "Fred Johnson, etc.),
the pathological resident idiot and attention whore of all the uk ngs,
blathered again:

FLUSH the sociopathic ******'s latest attention-baiting idiotic bull****
unread again


--
about Birdbrain Macaw's (now "James Wilkinson" LOL)
trolling:
"He is a well known attention seeking troll and every reply you
make feeds him.
Starts many threads most of which die quick as on the UK groups anyone
with sense Kill filed him ages ago which is why he now cross posts to
the US groups for a new audience.
This thread was unusual in that it derived and continued without him
to a large extent and his silly questioning is an attempt to get
noticed again."
MID:

--
ItsJoanNotJoann addressing Birdbrain Macaw's (now "James Wilkinson" LOL):
"You're an annoying troll and I'm done with you and your
stupidity."
MID:

--
AndyW addressing Birdbrain:
"Troll or idiot?...
You have been presented with a viewpoint with information, reasoning,
historical cases, citations and references to back it up and wilfully
ignore all going back to your idea which has no supporting information."
MID:

--
Phil Lee adressing Birdbrain Macaw:
"You are too stupid to be wasting oxygen."
MID:

--
Phil Lee describing Birdbrain Macaw:
"I've never seen such misplaced pride in being a ****ing moronic motorist."
MID:

--
Tony944 addressing Birdbrain Macaw:
"I seen and heard many people but you are on top of list being first class
ass hole jerk. ...You fit under unconditional Idiot and should be put in
mental institution.
MID:

--
Pelican to Birdbrain Macaw:
"Ok. I'm persuaded . You are an idiot."
MID:

--
DerbyDad03 addressing Birdbrain Macaw (now "James Wilkinson" LOL):
"Frigging Idiot. Get the hell out of my thread."
MID:

--
Kerr Mudd-John about Birdbrain Macaw (now "James Wilkinson" LOL):
"It's like arguing with a demented frog."
MID:

--
Mr Pounder Esquire about Birdbrain Macaw (now "James Wilkinson" LOL):
"the **** poor delivery boy with no hot running water, 11 cats and
several parrots living in his hovel."
MID:

--
Rob Morley about Birdbrain:
"He's a perennial idiot"
MID: 20170519215057.56a1f1d4@Mars

--
JoeyDee to Birdbrain
"I apologize for thinking you were a jerk. You're just someone with an IQ
lower than your age, and I accept that as a reason for your comments."
MID: l-september.org

--
Sam Plusnet about Birdbrain (now "James Wilkinson Sword" LOL):
"He's just desperate to be noticed. Any attention will do, no matter how
negative it may be."
MID:

--
asking Birdbrain:
"What, were you dropped on your head as a child?"
MID:

--
Christie addressing endlessly driveling Birdbrain Macaw (now "James
Wilkinson" LOL):
"What are you resurrecting that old post of mine for? It's from last
month some time. You're like a dog who's just dug up an old bone they
hid in the garden until they were ready to have another go at it."
MID:

--
Mr Pounder's fitting description of Birdbrain Macaw:
"You are a well known fool, a tosser, a pillock, a stupid unemployable
sponging failure who will always live alone and will die alone. You will not
be missed."
MID:

--
Richard to pathetic ****** Hucker:
"You haven't bred?
Only useful thing you've done in your pathetic existence."
MID:

--
about Birdbrain (now "James Wilkinson" LOL):
""not the sharpest knife in the drawer"'s parents sure made a serious
mistake having him born alive -- A total waste of oxygen, food, space,
and bandwidth."
MID:

--
Mr Pounder exposing sociopathic Birdbrain:
"You will always be a lonely sociopath living in a ******** with no hot
running water with loads of stinking cats and a few parrots."
MID:

--
francis about Birdbrain (now "James Wilkinson" LOL):
"He seems to have a reputation as someone of limited intelligence"
MID:

--
Peter Moylan about Birdbrain (now "James Wilkinson" LOL):
"If people like JWS didn't exist, we would have to find some other way to
explain the concept of "invincible ignorance"."
MID:

--
Lewis about nym-shifting Birdbrain:
"Typical narcissist troll, thinks his **** is so grand he has the right to
try to force it on everyone."
MID:
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Default Lead acid battery charger (or alternator) switching to trickle with load present?

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.

I can understand it noticing a drop in charging current if the battery is
on its own, but what if a random changing load is connected, as there is
in a running car?


You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.

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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.

I can understand it noticing a drop in charging current if the battery is
on its own, but what if a random changing load is connected, as there is
in a running car?


You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current it's passing to the battery is going into the battery and not going straight across to the lights? If you look at the battery in your car, there are two or three thick wires coming off each terminal. One will go to the alternator, another to the fusebox for all the lights etc. Unless there's some clever circuitry monitoring each battery wire individually and subtracting the currents, the alternator can't tell the difference between a battery taking 12 amps, and a battery taking 2 amps plus lights taking 10 amps. The second one requires switching to trickle charge, the first doesn't.


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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Friday, June 21, 2019 at 4:54:51 PM UTC-4, Rod Speed wrote:
Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.


Except that the alternator doesn't know how much current is going
into the battery and how much is being used to power the car.
At least not in any car I've had. The alternator is tied directly
to the battery and that common point supplies the car. The alternator
can't switch to trickle charge either. EVery one I've seen, with
the car running normally, the voltage at the alternator/battery is
about 13.5 - 14V





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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 06:54:38 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


Does the unwashed Scottish ******'s taste THAT good, senile Rodent? He'll
certainly climax soon with your help, senile Ozzie cretin! LOL

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID:
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 22:18:56 +0100, trader_4 wrote:

On Friday, June 21, 2019 at 4:54:51 PM UTC-4, Rod Speed wrote:
Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.


Except that the alternator doesn't know how much current is going
into the battery and how much is being used to power the car.
At least not in any car I've had. The alternator is tied directly
to the battery and that common point supplies the car. The alternator
can't switch to trickle charge either. Every one I've seen, with
the car running normally, the voltage at the alternator/battery is
about 13.5 - 14V


I used to think the same, until someone in one of these newsgroups (on another topic about 6 months ago) said it drops the voltage or it would wear out the battery on long journeys. I tested my own car, by leaving the lights on for a bit, then starting it. The voltage was about 14.4. It dropped to 13.8 after the battery was filled up. The regulator must have detected the battery was full somehow and lowered the charging voltage.

Mind you after some googling, apparently a lead acid is happy being charged from 13.8 to 14.5 continuously. Although when I used to leave my car on a charger (an old Bradex car battery charger) at 14.5, it ****ed the battery after a few months. Maybe 14.5 is only ok in a car alternator circuit, which isn't usually running 24 hours a day. I think I'll always make sure it's 13.8 if it's on charge all the time - my car tends to randomly lose battery power overnight (to the alarm I believe). I was just wondering if I bought an intelligent car battery charger, whether it would ever switch down to trickle if the alarm was sucking juice, as such a charger may not expect any load. I currently have it connected to a bench supply at 13.8.
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Friday, June 21, 2019 at 5:14:50 PM UTC-4, Commander Kinsey wrote:
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.

I can understand it noticing a drop in charging current if the battery is
on its own, but what if a random changing load is connected, as there is
in a running car?


You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current it's passing to the battery is going into the battery and not going straight across to the lights? If you look at the battery in your car, there are two or three thick wires coming off each terminal. One will go to the alternator, another to the fusebox for all the lights etc.


See my other post. I agree with you, that's how every car I've worked on
has been wired. AFAIK, the voltage regulator just keeps ~13.5 to 14v
on the system, which has the alternator, battery and car loads all tied
together.




Unless there's some clever circuitry monitoring each battery wire individually and subtracting the currents, the alternator can't tell the difference between a battery taking 12 amps, and a battery taking 2 amps plus lights taking 10 amps. The second one requires switching to trickle charge, the first doesn't.

There is no trickle charge. Apparently car batteries are fine at ~14V
while the car is running, they don't overcharge and nothing bad happens.

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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 22:38:51 +0100, trader_4 wrote:

On Friday, June 21, 2019 at 5:14:50 PM UTC-4, Commander Kinsey wrote:
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the battery is
on its own, but what if a random changing load is connected, as there is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current it's passing to the battery is going into the battery and not going straight across to the lights? If you look at the battery in your car, there are two or three thick wires coming off each terminal. One will go to the alternator, another to the fusebox for all the lights etc.


See my other post. I agree with you, that's how every car I've worked on
has been wired. AFAIK, the voltage regulator just keeps ~13.5 to 14v
on the system, which has the alternator, battery and car loads all tied
together.


That doesn't explain why I observed my own car switching from 14.4 to 13.8, after someone told me they do that.

Unless there's some clever circuitry monitoring each battery wire individually and subtracting the currents, the alternator can't tell the difference between a battery taking 12 amps, and a battery taking 2 amps plus lights taking 10 amps. The second one requires switching to trickle charge, the first doesn't.


There is no trickle charge. Apparently car batteries are fine at ~14V
while the car is running, they don't overcharge and nothing bad happens.


I would agree. I probably broke my battery by having it at about 14.5V 24/7 for months. I had incorrectly assumed all car battery chargers (although this one was very old) would not overcharge. AFAIK that charger was just a transformer and diodes, made to give out about the right voltage, probably made just for a single overnight charge. It's strange as the battery was only taking about half an amp when full, although I guess that's 7 watts of heat being constantly dissipated inside it.


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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?* I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


The voltage perhaps.

--
Max Demian
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Default Troll-feeding Senile IDIOT Alert!

On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian, another brain dead,
troll-feeding senile asshole, blathered:


The voltage perhaps.


What kind of a troll-feeding asshole are YOU?
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


The voltage perhaps.


Why would the voltage change? That's determined by the alternator or charger. Let's say the charger/alternator gives out 14.4V initially, to charge the battery quickly. It'll just sit at 14.4V forever, providing the charger can give out enough current to charge the slightly flat battery and power any connected loads. If the battery had no loads connected, it would take a lot less current when it became full, but the voltage would stay the same. If the charger monitored the current it was providing, how does it know if the battery is still charging at 10 amps, or if the battery is full and there's a 10 amp load?
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Default Troll-feeding Senile ASSHOLE Alert!

On Fri, 21 Jun 2019 14:38:51 -0700 (PDT), tardo_4, another mentally
challenged, troll-feeding, senile Yankietard, blathered again:


See my other post. I agree with you,


Yet another senile Yankietard who is so miserable and demented, he needs to
feed the dumbest troll around, even though he knows what the troll is about!
Poor decaying America! tsk
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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed
wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.

I can understand it noticing a drop in charging current if the battery
is
on its own, but what if a random changing load is connected, as there is
in a running car?


You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current it's
passing to the battery is going into the battery and not going straight
across to the lights?


The computer knows whats going to the battery and you can see that with an
ODB2 dongle.

If you look at the battery in your car, there are two or three thick wires
coming off each terminal. One will go to the alternator, another to the
fusebox for all the lights etc.


And it's the voltage across the one going from the alternator to the battery
that allows the computer to know how much current is going to the battery.

Unless there's some clever circuitry monitoring each battery wire
individually and subtracting the currents,


Yes there is, its called the computer.

the alternator can't tell the difference between a battery taking 12 amps,
and a battery taking 2 amps plus lights taking 10 amps.


But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first doesn't.




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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"trader_4" wrote in message
...
On Friday, June 21, 2019 at 4:54:51 PM UTC-4, Rod Speed wrote:
Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.


Except that the alternator doesn't know how much current
is going into the battery and how much is being used to
power the car.At least not in any car I've had.


Have fun explaining how you can have an ammeter
which shows the current that is going to the battery.

Ditto with an OBD2 dongle.

The alternator is tied directly to the battery


Yes.

and that common point supplies the car.


Nope. And there isnt normally just the
one wire at the positive battery terminal.


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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 23:39:34 +0100, Rod Speed wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed
wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the battery
is
on its own, but what if a random changing load is connected, as there is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current it's
passing to the battery is going into the battery and not going straight
across to the lights?


The computer knows whats going to the battery and you can see that with an
ODB2 dongle.


My dongle only lists faults.

If you look at the battery in your car, there are two or three thick wires
coming off each terminal. One will go to the alternator, another to the
fusebox for all the lights etc.


And it's the voltage across the one going from the alternator to the battery
that allows the computer to know how much current is going to the battery.


Bull****. How could it possibly know if the current flows into the battery or goes to the other wire leading to the fusebox?

Unless there's some clever circuitry monitoring each battery wire
individually and subtracting the currents,


Yes there is, its called the computer.


So what happened with older cars before they did that?

the alternator can't tell the difference between a battery taking 12 amps,
and a battery taking 2 amps plus lights taking 10 amps.


But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first doesn't.

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Default Lead acid battery charger (or alternator) switching to trickle with load present?

On Fri, 21 Jun 2019 23:15:21 +0100, "Commander Kinsey"
wrote:

On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


The voltage perhaps.


Why would the voltage change? That's determined by the alternator or charger. Let's say the charger/alternator gives out 14.4V initially, to charge the battery quickly. It'll just sit at 14.4V forever, providing the charger can give out enough current to charge the slightly flat battery and power any connected loads. If the battery had no loads connected, it would take a lot less current when it became full, but the voltage would stay the same. If the charger monitored the current it was providing, how does it know if the battery is still charging at 10 amps, or if the battery is full and there's a 10 amp load?


Not really true with anything but the most primative regulator like
you might see on an old outboard. Voltage is regulated somewhere
between 13.x and 14.x, not just reflecting what the alternator can do
against the load.
Rod is right, they look at current from the alternator There is
nothing they can do about the load so they don't give a **** about the
lights. The regulator just watches alternator current and cranks up
the voltage to keep it up. When current drops off it is either because
there is less load or because the battery is taking less of a charge.
That is when the voltage ramps down.
If current gets really low, like the battery is charged and there is
not much load they hit the bottom of the range ... essentially a
trickle charger that is also running the radio and heater fan.


As for a smart charger, usually the voltage is all they need to know.
When the voltage drop across the battery starts to rise. it indicates
the battery is charging and at a certain point they either turn off or
turn to trickle.
Different batteries have different "fully charged" voltage levels so
they usually have a switch for different types . (deep cycle, AGM etc)

Lithium batteries are a whole other thing and have smarter chargers
matched to the battery. Mix them up and your pants might really be on
fire.
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 23:44:24 +0100, Rod Speed wrote:



"trader_4" wrote in message
...
On Friday, June 21, 2019 at 4:54:51 PM UTC-4, Rod Speed wrote:
Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.


Except that the alternator doesn't know how much current
is going into the battery and how much is being used to
power the car.At least not in any car I've had.


Have fun explaining how you can have an ammeter
which shows the current that is going to the battery.


Er that's what he just said, it can't. The car must have more than one meter, on every wire coming from the battery, so it knows what's being consumed and what's used for charging.

Ditto with an OBD2 dongle.

The alternator is tied directly to the battery


Yes.

and that common point supplies the car.


Nope. And there isnt normally just the
one wire at the positive battery terminal.


I believe mine has three. Alternator, starter, everything else. The alternator itself can't know where it's current goes once it reaches the battery terminal. Does it go to the lights or into the battery itself?
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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 08:39:34 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


The computer knows


The troll knows how to bait all you senile assholes successfully, senile
asshole!

--
Sqwertz to Rot Speed:
"This is just a hunch, but I'm betting you're kinda an argumentative
asshole.
MID:


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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 23:48:01 +0100, wrote:

On Fri, 21 Jun 2019 23:15:21 +0100, "Commander Kinsey"
wrote:

On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?

The voltage perhaps.


Why would the voltage change? That's determined by the alternator or charger. Let's say the charger/alternator gives out 14.4V initially, to charge the battery quickly. It'll just sit at 14.4V forever, providing the charger can give out enough current to charge the slightly flat battery and power any connected loads. If the battery had no loads connected, it would take a lot less current when it became full, but the voltage would stay the same. If the charger monitored the current it was providing, how does it know if the battery is still charging at 10 amps, or if the battery is full and there's a 10 amp load?


Not really true with anything but the most primative regulator like
you might see on an old outboard. Voltage is regulated somewhere
between 13.x and 14.x, not just reflecting what the alternator can do
against the load.
Rod is right, they look at current from the alternator There is
nothing they can do about the load so they don't give a **** about the
lights. The regulator just watches alternator current and cranks up
the voltage to keep it up. When current drops off it is either because
there is less load or because the battery is taking less of a charge.
That is when the voltage ramps down.
If current gets really low, like the battery is charged and there is
not much load they hit the bottom of the range ... essentially a
trickle charger that is also running the radio and heater fan.


Take this situation: You start your car with the battery 3/4s full. The alternator provides a high voltage and charges it quickly. It's dark and cold, you have demisters, lights, etc on. How does the alternator know when the battery is full? As current will continue to be taken from it to power all those loads.

As for a smart charger, usually the voltage is all they need to know.
When the voltage drop across the battery starts to rise. it indicates
the battery is charging and at a certain point they either turn off or
turn to trickle.
Different batteries have different "fully charged" voltage levels so
they usually have a switch for different types . (deep cycle, AGM etc)


I guess charging a car battery with a charger plugged into the house won't work if you have a load in the car like lights (or in my case a faulty alarm). The charger will think the battery is still drawing a fair current and isn't full, when in fact it's the load eating it up.

Lithium batteries are a whole other thing and have smarter chargers
matched to the battery. Mix them up and your pants might really be on
fire.


Lithium are actually very easy to charge. For a single cell, just provide 4.2V, with the current limited to what it could handle (or what the charger can handle). A lithium cell will take virtually zero current when full if you give it 4.2V. It in fact will stay at 4.2V when you disconnect it from the charger. I have a charger here for 18650 torch cells - I think it's just a 4.2V 1A current limited voltage regulated supply. Up to an amp, up to 4.2V.
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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian
wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


The voltage perhaps.


Why would the voltage change?


That's the way batterys work, the battery voltage does change as its
charged.

That's determined by the alternator or charger.


Nope.

Let's say the charger/alternator gives out 14.4V initially, to charge the
battery quickly. It'll just sit at 14.4V forever, providing the charger
can give out enough current to charge the slightly flat battery and power
any connected loads.


Its more complicated than that with the current going to the battery and the
battery is charged.

If the battery had no loads connected, it would take a lot less current
when it became full, but the voltage would stay the same.


No it doesn't even with a very crude battery charger.

If the charger monitored the current it was providing, how does it know if
the battery is still charging at 10 amps, or if the battery is full and
there's a 10 amp load?


By checking the current actually being delivered to the battery.

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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 08:57:52 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


That's the way batterys work


That's the way how your and his trolling work, you senile asshole troll!

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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 23:39:34 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed
wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the battery
is
on its own, but what if a random changing load is connected, as there
is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.


But how can the regulator on the alternator possibly know the current
it's
passing to the battery is going into the battery and not going straight
across to the lights?


The computer knows whats going to the battery and you can see that with
an ODB2 dongle.


My dongle only lists faults.


Because it's a steaming turd with wheels frog car.

Most show all sorts of things.

If you look at the battery in your car, there are two or three thick
wires
coming off each terminal. One will go to the alternator, another to the
fusebox for all the lights etc.


And it's the voltage across the one going from the alternator to the
battery
that allows the computer to know how much current is going to the
battery.


Bull****.


We'll see...

How could it possibly know if the current flows into the battery or goes
to the other wire leading to the fusebox?


By measuring the voltage drop across those cables, stupid.

Unless there's some clever circuitry monitoring each

battery wire individually and subtracting the currents,


Yes there is, its called the computer.


So what happened with older cars before they did that?


The voltage across the battery changes as the battery is charged.

the alternator can't tell the difference between a battery taking 12
amps,
and a battery taking 2 amps plus lights taking 10 amps.


But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first doesn't.




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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Fri, 21 Jun 2019 23:57:52 +0100, Rod Speed wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian
wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?

The voltage perhaps.


Why would the voltage change?


That's the way batterys work, the battery voltage does change as its
charged.

That's determined by the alternator or charger.


Nope.


Yip. I can put any voltage I like across a battery's terminals. The battery then chooses how much current is drawn.

Let's say the charger/alternator gives out 14.4V initially, to charge the
battery quickly. It'll just sit at 14.4V forever, providing the charger
can give out enough current to charge the slightly flat battery and power
any connected loads.


Its more complicated than that with the current going to the battery and the
battery is charged.

If the battery had no loads connected, it would take a lot less current
when it became full, but the voltage would stay the same.


No it doesn't even with a very crude battery charger.


For example, I'm currently keeping my car's battery topped up with a bench supply overnight. It's set to 13.8V, with a current limiter only to prevent overloading the supply. The voltage stays at 13.8V all the time, sometimes 100mA is drawn, sometimes up to 4A. The only way I or the supply can tell the battery is full, is by the current dropping to 100mA. But it's actually always full, as when 4A is drawn, that's going to a load.

If the charger monitored the current it was providing, how does it know if
the battery is still charging at 10 amps, or if the battery is full and
there's a 10 amp load?


By checking the current actually being delivered to the battery.


I guess that may be true, if the car's computer has two ammeters and subtracts one from the other. But AFAIK, the alternator regulator only works by it's own current sensor. And that current could be going into the battery, or past it to the loads.
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On Sat, 22 Jun 2019 00:26:13 +0100, Rod Speed wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 23:39:34 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed
wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the battery
is
on its own, but what if a random changing load is connected, as there
is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.

But how can the regulator on the alternator possibly know the current
it's
passing to the battery is going into the battery and not going straight
across to the lights?


The computer knows whats going to the battery and you can see that with
an ODB2 dongle.


My dongle only lists faults.


Because it's a steaming turd with wheels frog car.


Which should adhere to the ****ing OBD standards according to the frog's own EU regs!!

And a very basic OBD reader I bought to determine why a warning light was on.

Most show all sorts of things.

If you look at the battery in your car, there are two or three thick
wires
coming off each terminal. One will go to the alternator, another to the
fusebox for all the lights etc.

And it's the voltage across the one going from the alternator to the
battery that allows the computer to know how much current is going to the
battery.


Bull****.


We'll see...

How could it possibly know if the current flows into the battery or goes
to the other wire leading to the fusebox?


By measuring the voltage drop across those cables, stupid.

Unless there's some clever circuitry monitoring each
battery wire individually and subtracting the currents,


Yes there is, its called the computer.


So what happened with older cars before they did that?


The voltage across the battery changes as the battery is charged.


Wrong. Say the alternator can produce 14V at up to 50 amps. When the battery has been used to start the car and perhaps run some lights when the engine was off, it takes maybe 25A, and the voltage is 14V, regulated by the alternator's circuitry. When the battery becomes full, it takes only a fraction of an amp, but the voltage is still 14V. What needs to be measured is the current going into the battery, and that cannot be done by just measuring the current coming from the alternator, as that could also be going to lights, heaters, spark plugs, etc, etc.

the alternator can't tell the difference between a battery taking 12
amps,
and a battery taking 2 amps plus lights taking 10 amps.

But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first doesn't.

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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 09:26:13 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the two clinically insane asshole's latest troll**** unread


--
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"**** you're thick/pathetic excuse for a troll."
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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 23:57:52 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian
wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?

The voltage perhaps.


Why would the voltage change?


That's the way batterys work, the battery voltage does change as its
charged.

That's determined by the alternator or charger.


Nope.


Yip.


Nope.

I can put any voltage I like across a battery's terminals.


Nope.

The battery then chooses how much current is drawn.


And that current changes depending on the how charged the battery is.

Let's say the charger/alternator gives out 14.4V initially, to charge
the
battery quickly. It'll just sit at 14.4V forever, providing the charger
can give out enough current to charge the slightly flat battery and
power
any connected loads.


Its more complicated than that with the current going to the battery and
the
battery is charged.

If the battery had no loads connected, it would take a lot less current
when it became full, but the voltage would stay the same.


No it doesn't even with a very crude battery charger.


For example, I'm currently keeping my car's battery topped up with a bench
supply overnight. It's set to 13.8V, with a current limiter only to
prevent overloading the supply.


It actually specify the current being supplied.

The voltage stays at 13.8V all the time, sometimes 100mA is drawn,
sometimes up to 4A. The only way I or the supply can tell the battery is
full, is by the current dropping to 100mA. But it's actually always full,
as when 4A is drawn, that's going to a load.


What load ? There no load with a battery being charged with a bench supply.

If the charger monitored the current it was providing, how does it know
if the battery is still charging at 10 amps, or if the battery is full
and there's a 10 amp load?


By checking the current actually being delivered to the battery.


I guess that may be true, if the car's computer has two ammeters


It has more than one wire to the positive terminal of the battery.
So it can see what current is going to the rest of the car.

and subtracts one from the other. But AFAIK, the alternator regulator
only works by it's own current sensor. And that current could be going
into the battery, or past it to the loads.


Not when there is more than one wire going to the
positive terminal of the battery, and there always is.

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Default Lead acid battery charger (or alternator) switching to trickle with load present?

On Fri, 21 Jun 2019 23:55:31 +0100, "Commander Kinsey"
wrote:

On Fri, 21 Jun 2019 23:48:01 +0100, wrote:

On Fri, 21 Jun 2019 23:15:21 +0100, "Commander Kinsey"
wrote:

On Fri, 21 Jun 2019 22:57:44 +0100, Max Demian wrote:

On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge? I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?

The voltage perhaps.

Why would the voltage change? That's determined by the alternator or charger. Let's say the charger/alternator gives out 14.4V initially, to charge the battery quickly. It'll just sit at 14.4V forever, providing the charger can give out enough current to charge the slightly flat battery and power any connected loads. If the battery had no loads connected, it would take a lot less current when it became full, but the voltage would stay the same. If the charger monitored the current it was providing, how does it know if the battery is still charging at 10 amps, or if the battery is full and there's a 10 amp load?


Not really true with anything but the most primative regulator like
you might see on an old outboard. Voltage is regulated somewhere
between 13.x and 14.x, not just reflecting what the alternator can do
against the load.
Rod is right, they look at current from the alternator There is
nothing they can do about the load so they don't give a **** about the
lights. The regulator just watches alternator current and cranks up
the voltage to keep it up. When current drops off it is either because
there is less load or because the battery is taking less of a charge.
That is when the voltage ramps down.
If current gets really low, like the battery is charged and there is
not much load they hit the bottom of the range ... essentially a
trickle charger that is also running the radio and heater fan.


Take this situation: You start your car with the battery 3/4s full. The alternator provides a high voltage and charges it quickly. It's dark and cold, you have demisters, lights, etc on. How does the alternator know when the battery is full? As current will continue to be taken from it to power all those loads.

As for a smart charger, usually the voltage is all they need to know.
When the voltage drop across the battery starts to rise. it indicates
the battery is charging and at a certain point they either turn off or
turn to trickle.
Different batteries have different "fully charged" voltage levels so
they usually have a switch for different types . (deep cycle, AGM etc)


I guess charging a car battery with a charger plugged into the house won't work if you have a load in the car like lights (or in my case a faulty alarm). The charger will think the battery is still drawing a fair current and isn't full, when in fact it's the load eating it up.


Plug in chargers are voltage regulated so that load would pull the
voltage down and the charger would try to bring it up. Once the
battery was charged the charger would either see a higher voltage and
ramp down or it would stay there at. what it could drive. That is
probably a good reason to turn all that crap off when you are charging
a battery off line and you might want to take the negative lead to the
car loose if you have too much residual load. Maybe you could figure
out what was killing the battery in the first place then.


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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Sat, 22 Jun 2019 00:26:13 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 23:39:34 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed

wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when
to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the
battery
is
on its own, but what if a random changing load is connected, as
there
is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.

But how can the regulator on the alternator possibly know the current
it's
passing to the battery is going into the battery and not going
straight
across to the lights?


The computer knows whats going to the battery and you can see that with
an ODB2 dongle.

My dongle only lists faults.


Because it's a steaming turd with wheels frog car.


Which should adhere to the ****ing OBD standards according to the frog's
own EU regs!!


Steaming turd frog cars don't work like that.

And a very basic OBD reader I bought to determine why a warning light was
on.


Should still show that other stuff.

Most show all sorts of things.

If you look at the battery in your car, there are two or three thick
wires
coming off each terminal. One will go to the alternator, another to
the
fusebox for all the lights etc.

And it's the voltage across the one going from the alternator to the
battery that allows the computer to know how much current is going to
the
battery.


Bull****.


We'll see...

How could it possibly know if the current flows into the battery or goes
to the other wire leading to the fusebox?


By measuring the voltage drop across those cables, stupid.

Unless there's some clever circuitry monitoring each
battery wire individually and subtracting the currents,


Yes there is, its called the computer.


So what happened with older cars before they did that?


The voltage across the battery changes as the battery is charged.


Wrong.


Nope,

Say the alternator can produce 14V at up to 50 amps. When the battery has
been used to start the car and perhaps run some lights when the engine was
off, it takes maybe 25A, and the voltage is 14V,


Yes.

regulated by the alternator's circuitry.


Nope, buy the battery, and you can prove that with the bench supply.

When the battery becomes full, it takes only a fraction of an amp,


Yep, because the battery voltage has risen.

but the voltage is still 14V.


Nope, and you previously said it wasn't.

What needs to be measured is the current going into the battery,


That's what the computer does.

and that cannot be done by just measuring the current coming from the
alternator,


Yes, that's why there is more than one wire on the battery positive
terminal.

as that could also be going to lights, heaters, spark plugs, etc, etc.


Yes, that's why there is more than one wire on the battery positive
terminal.

the alternator can't tell the difference between a battery taking 12
amps,
and a battery taking 2 amps plus lights taking 10 amps.

But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first
doesn't.


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Default Lead acid battery charger (or alternator) switching to trickle with load present?



"Commander Kinsey" wrote in message
news
On Sat, 22 Jun 2019 00:26:13 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news
On Fri, 21 Jun 2019 23:39:34 +0100, Rod Speed
wrote:



"Commander Kinsey" wrote in message
news On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed

wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when
to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the
battery
is
on its own, but what if a random changing load is connected, as
there
is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.

But how can the regulator on the alternator possibly know the current
it's
passing to the battery is going into the battery and not going
straight
across to the lights?


The computer knows whats going to the battery and you can see that with
an ODB2 dongle.

My dongle only lists faults.


Because it's a steaming turd with wheels frog car.


Which should adhere to the ****ing OBD standards according to the frog's
own EU regs!!


Steaming turd with wheels frog cars don't. And that isnt an EU reg anyway.

And a very basic OBD reader I bought to determine why a warning light was
on.


That will still show more than just faults.

Most show all sorts of things.

If you look at the battery in your car, there are two or three thick
wires
coming off each terminal. One will go to the alternator, another to
the
fusebox for all the lights etc.

And it's the voltage across the one going from the alternator to the
battery that allows the computer to know how much current is going to
the
battery.


Bull****.


We'll see...

How could it possibly know if the current flows into the battery or goes
to the other wire leading to the fusebox?


By measuring the voltage drop across those cables, stupid.

Unless there's some clever circuitry monitoring each
battery wire individually and subtracting the currents,


Yes there is, its called the computer.


So what happened with older cars before they did that?


The voltage across the battery changes as the battery is charged.


Wrong.


Nope.

Say the alternator can produce 14V at up to 50 amps. When the battery has
been used to start the car and perhaps run some lights when the engine was
off, it takes maybe 25A, and the voltage is 14V,


Yep.

regulated by the alternator's circuitry.


Nope, by the battery.

When the battery becomes full, it takes only a fraction of an amp,


Yep, because the battery voltage is now higher.

but the voltage is still 14V.


The battery voltage isnt.

What needs to be measured is the current going into the battery,


Nope, the current drops automatically.

and that cannot be done by just measuring the current coming from the
alternator, as that could also be going to lights, heaters, spark plugs,
etc, etc.


That's why there is more than one wire to the battery positive terminal.

the alternator can't tell the difference between a battery taking 12
amps,
and a battery taking 2 amps plus lights taking 10 amps.

But the computer can. And knows if the lights are on too.

The second one requires switching to trickle charge, the first
doesn't.


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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On 22/6/19 7:54 am, Commander Kinsey wrote:
On Fri, 21 Jun 2019 22:38:51 +0100, trader_4 wrote:

On Friday, June 21, 2019 at 5:14:50 PM UTC-4, Commander Kinsey wrote:
On Fri, 21 Jun 2019 21:54:38 +0100, Rod Speed
wrote:

Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?

From the current the battery takes.

I can understand it noticing a drop in charging current if the
battery is
on its own, but what if a random changing load is connected, as
there is
in a running car?

You just look at the current going to the battery. The variably
loads like with lights isnt supplied by the battery when the
engine is running, its supplied by the alternator.

But how can the regulator on the alternator possibly know the current
it's passing to the battery is going into the battery and not going
straight across to the lights?* If you look at the battery in your
car, there are two or three thick wires coming off each terminal.
One will go to the alternator, another to the fusebox for all the
lights etc.


See my other post.* I agree with you, that's how every car I've worked on
has been wired.* AFAIK, the voltage regulator just keeps ~13.5 to 14v
on the system, which has the alternator, battery and car loads all tied
together.


13.8 - 14.2 is the normal charge range. They will start out high when
charging and drop back to the lower range when the battery reaches full
charge. 14.4 is a tad on the high side and might gas the batteries up a
little. BTW, trickle charge relates to the charging *current*, not the
voltage. A 1 amp trickle charge will keep a battery topped up against
natural charge loss when unused.

That doesn't explain why I observed my own car switching from 14.4 to
13.8, after someone told me they do that.


Yes, they do that but it isn't *switching* per se. They drop to the
lower voltage as the battery becomes charged. Turning a load on, like
the headlights, will cause a more sudden increase in voltage since you
have increased the current requirements. The battery is a *load* on the
system and so is anything you turn on.

*Unless there's some clever circuitry monitoring each battery wire
individually and subtracting the currents, the alternator can't tell
the difference between a battery taking 12 amps, and a battery taking
2 amps plus lights taking 10 amps.* The second one requires switching
to trickle charge, the first doesn't.


There is no trickle charge.* Apparently car batteries are fine at ~14V
while the car is running, they don't overcharge and nothing bad happens.


I would agree.* I probably broke my battery by having it at about 14.5V
24/7 for months.* I had incorrectly assumed all car battery chargers
(although this one was very old) would not overcharge.* AFAIK that
charger was just a transformer and diodes, made to give out about the
right voltage, probably made just for a single overnight charge.* It's
strange as the battery was only taking about half an amp when full,
although I guess that's 7 watts of heat being constantly dissipated
inside it.


13.8 is the normal maximum charge you want to be putting into that
battery. anything over runs a risk of gassing, etc. ie. overcharging.

--

Xeno


Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)
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Default Lead acid battery charger (or alternator) switching to tricklewith load present?

On 21/06/2019 22:57, Max Demian wrote:
On 21/06/2019 21:19, Commander Kinsey wrote:
How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?Â* I can understand it noticing a drop in
charging current if the battery is on its own, but what if a random
changing load is connected, as there is in a running car?


The voltage perhaps.

Definitely. One of the simplest ways to msake a vcarger is to have a
constant voltage source in series with somem form of resistor. As the
terminal voltage rises so too does the charge current drop.

The problem that brings is when a heavy cirrent is siltanoeusly drawn
from the battery.

Which is why car alternator control is a little more spohisticated than
that.


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a car with the cramped public exposure of €¨an airplane.€

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Default Lead acid battery charger (or alternator) switching to trickle with load present?

trader_4 wrote:
On Friday, June 21, 2019 at 4:54:51 PM UTC-4, Rod Speed wrote:
Commander Kinsey wrote

How does a lead acid battery charger (or car alternator) know when to
switch to trickle charge?


From the current the battery takes.


Except that the alternator doesn't know how much current is going
into the battery and how much is being used to power the car.
At least not in any car I've had. The alternator is tied directly
to the battery and that common point supplies the car. The alternator
can't switch to trickle charge either. EVery one I've seen, with
the car running normally, the voltage at the alternator/battery is
about 13.5 - 14V


Some better home chargers measure voltage, and temperature, and apply some
kind of program. My Chevy seems to cut off charge completely at times,
depending on some sort of program. That's scary cause looks like alternator
is bad.

Greg


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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 09:26:13 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


We'll see...


We'll see YOU trolling on these groups like there was no tomorrow, you
85-year-old senile pest!

--
Keema Nam addressing nym-shifting senile Rodent:
"You are now exposed as a liar, as well as an ignorant troll."
"MID: .com"
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Default Lonely Psychopathic Senile Ozzie Troll Alert!

FLUSH another 142 !!! lines of absolutel troll**** unread again

--
addressing nym-shifting senile Rodent:
"You on the other hand are a heavyweight bull****ter who demonstrates
your particular prowess at it every day."
MID:
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FLUSH another 137 !!! lines of the two asshole trolls' latest troll****
unread

--
Richard addressing Rot Speed:
"**** you're thick/pathetic excuse for a troll."
MID:

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Default Lonely Psychopathic Senile Ozzie Troll Alert!

On Sat, 22 Jun 2019 09:57:57 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the two prize idiots' endless troll****

Not when there is more than one wire going to the
positive terminal of the battery, and there always is.


In auto-contradicting mode again, you clinically insane auto-contradicting
senile asshole? G

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
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Default Troll-feeding Senile IDIOT Alert!

On Sat, 22 Jun 2019 14:07:32 +1000, Xeno, another brain damaged,
troll-feeding, senile Australian idiot, blathered:

13.8 - 14.2 is the normal


There is NOTHING normal about the clinically insane sociopath's and
attention whore's idiotic "threads" in all these groups, you brain dead,
troll-feeding, senile Australian idiot!
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