Alternator voltage should stay around 13.6- 13.8
Higher voltages indicates a discharged battery or cold outside temp
Higher voltages indicates a discharged battery or cold outside temp
AZ Reman Alternator rarely pulls more than 14.0v
- Thread starter ThunderOne
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Originally Posted By: joel95ex
the AZ alternators i had were HORRIBLE. one died in less than a month. went through all the checks and after the 3rd or 4th "free replacement" i got my money back and went and bought one at advance auto which outlasted all of the AZ remans combined. that was on my accord.
I got a reman alt from AAP for the GTI that after one week got a clutch rattle and dispersed fine metal shaving all over the engine.
Second one seems ok so far. I think all the remans are a bit hit or miss. There is a post on one of the VW forums from a guy who exchanged his 5 times in a short period of time.
the AZ alternators i had were HORRIBLE. one died in less than a month. went through all the checks and after the 3rd or 4th "free replacement" i got my money back and went and bought one at advance auto which outlasted all of the AZ remans combined. that was on my accord.
I got a reman alt from AAP for the GTI that after one week got a clutch rattle and dispersed fine metal shaving all over the engine.
Second one seems ok so far. I think all the remans are a bit hit or miss. There is a post on one of the VW forums from a guy who exchanged his 5 times in a short period of time.
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The alternator is controlled by the voltage regulator. It makes enough amperage( upto its maximum at that specific rpm and alternator temperature, and the limits of the cabling) to maintian the voltage the Voltage regulator is asking for.
Voltage is electrical pressure. It pushes, it does not pull.
Each and every vehicle will be different as to what voltage its voltage regulator decides to ask for.
The location of the voltage regulator, whether an external unit, or internal to the alternator or internal to the engine computer is a huge factor as well.
And when a battery is well discharged, it can be accepting 50 amps, and still be below 14 volts. When fully charged it might only require 1 amp to hold that battery at 14 volts.
So the OP could merely be looking at system voltage when the battery is well discharged and te alternator is making everything it can at idle.
If the battery were fully charged, by a plug in charger, then very little of the alternators amperage would be going into the battery, most all of it would be powering the ignition, fuel pump, lights, any other DC load runnig at that time.
Also, most reman alternators come with a little note saying to fully charge th battery before starting the vehicle. the reason is the new brushes are not broken in, and the voltage regulator seeking mid 14'safter starting will dump some 9 amps perhaps more of field current into those brushes to ask everything possible from the alternator, and those brushes surface contact with commutator is too small, as they have not broken in yet.
The ability of batteries, and their charging sources are very much misunderstood by a significant majority.
Voltage readings alone tell a very small part of the story. How many ampheres are flowing from alternator into battery tell almost the Whole story.
So voltage readings are not just misleading, they can send the observer of them in a complete wrong direction.
Charge the delpeted battery on a grid powered charger. The battery would prefer to always, always be 100% charged.
Do not think the voltage one sees right after starting, is the voltage that he vehicle will always hold.
Each vehicle will be different as to what voltage it seeks, and what voltage it decides to hold, and for how long
Do not think that even experienced mechanics have a good grasp of voltage and amperage.
A healthy but well discharged battery can easily accept 65 amps. It can take 20 plus minutes of 65 amps before its voltage rises to 14.4 volts.
An alternator might be rated at 130 amps. it can proiduce this when cold, and spinning fast. It might only be able to produce 50 amps at idle.
But the healthy but deplted battery can accept all of those 50 amps. but 12 of those amps are likely going into powering the engine ignition and fuel pump.
The result is one might only see 13.2v system voltage, at idle, as the alternator can only make 50 amps and 12 of those are powering the dc loads and the remaining 38 are going into the battery. So system voltage will lag in the low 13v range and slowly rise from there, until the battery has refilled to the 80% charged level, at which point the amps required to maintain mid 14's tapers rapidly and the amps required to maintain only 13.6 tapers significantly faster.
now if the battery were fully charged, it might only require 0.5 amps to be brought to 14.5 v, and an anternator capable of 50 amps at idle would have 0 issues powering all dc loads and holding the battery at 14.5v. it would get it there nearly instantly.
So unless one knows how many amps the battery is accepting, one does not really know its state of charge either, and a low system voltage at idle might be indicative only that the battery is well discharged and sucking up everything the alternator can make.
Voltage is electrical pressure. It pushes, it does not pull.
Each and every vehicle will be different as to what voltage its voltage regulator decides to ask for.
The location of the voltage regulator, whether an external unit, or internal to the alternator or internal to the engine computer is a huge factor as well.
And when a battery is well discharged, it can be accepting 50 amps, and still be below 14 volts. When fully charged it might only require 1 amp to hold that battery at 14 volts.
So the OP could merely be looking at system voltage when the battery is well discharged and te alternator is making everything it can at idle.
If the battery were fully charged, by a plug in charger, then very little of the alternators amperage would be going into the battery, most all of it would be powering the ignition, fuel pump, lights, any other DC load runnig at that time.
Also, most reman alternators come with a little note saying to fully charge th battery before starting the vehicle. the reason is the new brushes are not broken in, and the voltage regulator seeking mid 14'safter starting will dump some 9 amps perhaps more of field current into those brushes to ask everything possible from the alternator, and those brushes surface contact with commutator is too small, as they have not broken in yet.
The ability of batteries, and their charging sources are very much misunderstood by a significant majority.
Voltage readings alone tell a very small part of the story. How many ampheres are flowing from alternator into battery tell almost the Whole story.
So voltage readings are not just misleading, they can send the observer of them in a complete wrong direction.
Charge the delpeted battery on a grid powered charger. The battery would prefer to always, always be 100% charged.
Do not think the voltage one sees right after starting, is the voltage that he vehicle will always hold.
Each vehicle will be different as to what voltage it seeks, and what voltage it decides to hold, and for how long
Do not think that even experienced mechanics have a good grasp of voltage and amperage.
A healthy but well discharged battery can easily accept 65 amps. It can take 20 plus minutes of 65 amps before its voltage rises to 14.4 volts.
An alternator might be rated at 130 amps. it can proiduce this when cold, and spinning fast. It might only be able to produce 50 amps at idle.
But the healthy but deplted battery can accept all of those 50 amps. but 12 of those amps are likely going into powering the engine ignition and fuel pump.
The result is one might only see 13.2v system voltage, at idle, as the alternator can only make 50 amps and 12 of those are powering the dc loads and the remaining 38 are going into the battery. So system voltage will lag in the low 13v range and slowly rise from there, until the battery has refilled to the 80% charged level, at which point the amps required to maintain mid 14's tapers rapidly and the amps required to maintain only 13.6 tapers significantly faster.
now if the battery were fully charged, it might only require 0.5 amps to be brought to 14.5 v, and an anternator capable of 50 amps at idle would have 0 issues powering all dc loads and holding the battery at 14.5v. it would get it there nearly instantly.
So unless one knows how many amps the battery is accepting, one does not really know its state of charge either, and a low system voltage at idle might be indicative only that the battery is well discharged and sucking up everything the alternator can make.
Thanks for the response... I realize my subject title wasn't technically accurate.
My battery has a resting voltage of 12.55 when read at the terminals after 12 hours or so of not running the vehicle. So I think it is a healthy battery. When load tested it still has a supposed 580 CCA, vs the 750 it had new four years ago. I do not know how accurate a "CCA load test" is... so I try to just look at the resting voltage.
My battery has a resting voltage of 12.55 when read at the terminals after 12 hours or so of not running the vehicle. So I think it is a healthy battery. When load tested it still has a supposed 580 CCA, vs the 750 it had new four years ago. I do not know how accurate a "CCA load test" is... so I try to just look at the resting voltage.
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Few bother performing the CCA test on a new fully charged battery, but they usually beat their rating by at least 100 CCA.
In deep cycle marine usage, when a battery is capacity tested ( meaning loaded at precisely 5 amps per 100AH of capacity for 20 hours) and comes in at only 80% of capacity, the battery is considered end of life.
It of course could still provide its remaining capacity for quite some time, but the possibility of failure increases greatly after the capacity has diminished to 80% of original, and in a boat at sea battery failure is more than just inconvenient.
Keep in mind this on deep cycle or marine batteries which have thicker more durable plates than starting batteries. A startring battery coming in at only 80% of capacity would likely be much more prone to a prompt failure due to those thinner plates breaking and shorting out a cell.
12.55 12 hours after engine shutoff is not really a good number in my opinion.
Resting voltage is a bad indicator for several reasons, but more so when there is not a new fully charged reading of that same battery, to use for comparison on that same battery
I've seen flooded batteries be anywhere from 12.62 to 12.93v when fully charged and rested. If yours is a 12.62v full charge battery then 12.55 is not all that bad, but if it is a 12.93v fully charged battery then 12.55v is not good at all. People love to say a fully charged battery is 12.xx volts, but their actual full charge resting voltage varies very widely, and some AGMs can be as high as 13.16v
Also, if the battery is low on water, but the plates are still covered, then the voltage will read high and the battery will seem to perform well. Refill it to the proper level and the voltage is ugly low and performs poorly in load or capacity tests.
If you really want to get last possible engine start out of this battery before replacement, then get it on a grid powered charger, and do not rely on your vehicle's charging system to top it off, as it cannot, and will not, as it takes many hours at higher voltages than your vehicle will allow simply to get from 85% to 95% state of charge and that last 5%, especially on a sulfated battery can take many many more hours, at 14.5v.
In deep cycle marine usage, when a battery is capacity tested ( meaning loaded at precisely 5 amps per 100AH of capacity for 20 hours) and comes in at only 80% of capacity, the battery is considered end of life.
It of course could still provide its remaining capacity for quite some time, but the possibility of failure increases greatly after the capacity has diminished to 80% of original, and in a boat at sea battery failure is more than just inconvenient.
Keep in mind this on deep cycle or marine batteries which have thicker more durable plates than starting batteries. A startring battery coming in at only 80% of capacity would likely be much more prone to a prompt failure due to those thinner plates breaking and shorting out a cell.
12.55 12 hours after engine shutoff is not really a good number in my opinion.
Resting voltage is a bad indicator for several reasons, but more so when there is not a new fully charged reading of that same battery, to use for comparison on that same battery
I've seen flooded batteries be anywhere from 12.62 to 12.93v when fully charged and rested. If yours is a 12.62v full charge battery then 12.55 is not all that bad, but if it is a 12.93v fully charged battery then 12.55v is not good at all. People love to say a fully charged battery is 12.xx volts, but their actual full charge resting voltage varies very widely, and some AGMs can be as high as 13.16v
Also, if the battery is low on water, but the plates are still covered, then the voltage will read high and the battery will seem to perform well. Refill it to the proper level and the voltage is ugly low and performs poorly in load or capacity tests.
If you really want to get last possible engine start out of this battery before replacement, then get it on a grid powered charger, and do not rely on your vehicle's charging system to top it off, as it cannot, and will not, as it takes many hours at higher voltages than your vehicle will allow simply to get from 85% to 95% state of charge and that last 5%, especially on a sulfated battery can take many many more hours, at 14.5v.
Thanks wrcsixeight. It is a flooded battery, not an AGM. It should read around 12.6 volts but like you said, I do not have a new battery to compare it to. Last time I had to replace a battery, it was a red top Optima, and it had less than 10CCAs left. It was a great battery, right up until it died. That battery was on the truck for 6 or 7 years.
I do put my battery on a charger on occasion. I will check it the next day and hear it bubbling (or de-sulfating, not sure which), and it will have the voltage sitting at around 13.3 volts. I seems to never go much higher than this. Should I leave it on the charger for longer?
I have a li-ion jump starter in my truck at all times. I use it a couple times per year for camping purposes.
I do put my battery on a charger on occasion. I will check it the next day and hear it bubbling (or de-sulfating, not sure which), and it will have the voltage sitting at around 13.3 volts. I seems to never go much higher than this. Should I leave it on the charger for longer?
I have a li-ion jump starter in my truck at all times. I use it a couple times per year for camping purposes.
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Battery Voltage is often seen as a gas tank fuel level gauge, but it is not.
A charger holding a battery at 13.3v seems like it is a smart charger at 'float' or maintenance voltage. It is either that or a very discharged battery that has not had enough time at the charger's maximum amperage output to yet rise above 13.3v
Generally there are 3 stages of chargeing.
Bulk is when the charger it outputting everything it can in order to reach the max voltage, called absorption voltage. Voltage will climb from whatever the battery is at to the mid 14v range
Absorption voltage is a constant voltage phase in the 14.4 to 14.7v range. How long the charger decide to hold absorption voltage is very important, and most will not hold it long enough, for fear of overcharging, and lawyers.
how long to actually hold absorption voltage will vary from battery to battery and will vary according to the depth of discharge, temperature, health, age. Ideal absorption duration is not something any smart charger is going to get right on each and every battery from each and every state of discharge.
When amperage tapers to a low level at absorption voltage then the battery is likely nearly fully charged, but no Smart chargers actually ask for the capacity of the battery to determine what level of amperage to end the absorption phase at. Most are just holding absorption voltage for X amount of time, and X was determined by some labcoat seeking some acceptable compromise, and then adjusted according to the beancounters and lawyers.
Float stage is Not designed to charge the battery, but to maintain it at full charge after it is been fully charged at absorption voltage. Charging will still occur of a 90% charged battery at float voltage, but it is very very slow, compared to if the battery were still being held at absorption voltage.
Those who believe the charger's green light indicating full charge, should dip a hydrometer when their charger flashes that green light, and usually will see the battery is well less than fully charged. OTC 4619.
Any voltage over the nominal full charge restnig voltage of that specific battery will charge the battery, but generally one wants voltage to climb to the mid 14's, remain there for a period of time before reverting to float voltage. Whenever one has the opportunity to plug in a charger, Ideally one wants the battery to be 100% full when it is unplugged. the 'trickle charge it overnight' recommendation seen far and wide is almost a joke in that this trickle chargers will usually require days to max out specific gravity, but it depends on the voltage the charger seeks and how many amps it has available to seek that absorption voltage. Any level of charging on an undercharged batter yis better than No charging of it, but the trickle charge recommendation should join the old wives in their insane asylum.
Any time a battery is charged it is being desulfated. It is when those sulfates have hardened, because the battery has sat for a period and gone through an extended period remaining less than fully charged, that the pulse desulfation chargers are said to do their magic breaking up the hardened sulfates and restoring plate material to the chemical reaction.
These pulse desulfating chargers have been tested on sulfated batteries in controlled settings by marine experts and found to do nothing than an extended time at absorption voltage could not do.
Pulse desulfating has become the battery charger marketer's favorite word to include on the packaging, as it works, the marketing, not the pulses.
Preventing a smart charger from dropping to float voltage prematurely on an undercharged battery can yield almost magical desulfating results. The battery needs time held at higher electrical pressure. They almost never get it, and this reduces their capacity and ability compared to a battery that does.
A charger holding a battery at 13.3v seems like it is a smart charger at 'float' or maintenance voltage. It is either that or a very discharged battery that has not had enough time at the charger's maximum amperage output to yet rise above 13.3v
Generally there are 3 stages of chargeing.
Bulk is when the charger it outputting everything it can in order to reach the max voltage, called absorption voltage. Voltage will climb from whatever the battery is at to the mid 14v range
Absorption voltage is a constant voltage phase in the 14.4 to 14.7v range. How long the charger decide to hold absorption voltage is very important, and most will not hold it long enough, for fear of overcharging, and lawyers.
how long to actually hold absorption voltage will vary from battery to battery and will vary according to the depth of discharge, temperature, health, age. Ideal absorption duration is not something any smart charger is going to get right on each and every battery from each and every state of discharge.
When amperage tapers to a low level at absorption voltage then the battery is likely nearly fully charged, but no Smart chargers actually ask for the capacity of the battery to determine what level of amperage to end the absorption phase at. Most are just holding absorption voltage for X amount of time, and X was determined by some labcoat seeking some acceptable compromise, and then adjusted according to the beancounters and lawyers.
Float stage is Not designed to charge the battery, but to maintain it at full charge after it is been fully charged at absorption voltage. Charging will still occur of a 90% charged battery at float voltage, but it is very very slow, compared to if the battery were still being held at absorption voltage.
Those who believe the charger's green light indicating full charge, should dip a hydrometer when their charger flashes that green light, and usually will see the battery is well less than fully charged. OTC 4619.
Any voltage over the nominal full charge restnig voltage of that specific battery will charge the battery, but generally one wants voltage to climb to the mid 14's, remain there for a period of time before reverting to float voltage. Whenever one has the opportunity to plug in a charger, Ideally one wants the battery to be 100% full when it is unplugged. the 'trickle charge it overnight' recommendation seen far and wide is almost a joke in that this trickle chargers will usually require days to max out specific gravity, but it depends on the voltage the charger seeks and how many amps it has available to seek that absorption voltage. Any level of charging on an undercharged batter yis better than No charging of it, but the trickle charge recommendation should join the old wives in their insane asylum.
Any time a battery is charged it is being desulfated. It is when those sulfates have hardened, because the battery has sat for a period and gone through an extended period remaining less than fully charged, that the pulse desulfation chargers are said to do their magic breaking up the hardened sulfates and restoring plate material to the chemical reaction.
These pulse desulfating chargers have been tested on sulfated batteries in controlled settings by marine experts and found to do nothing than an extended time at absorption voltage could not do.
Pulse desulfating has become the battery charger marketer's favorite word to include on the packaging, as it works, the marketing, not the pulses.
Preventing a smart charger from dropping to float voltage prematurely on an undercharged battery can yield almost magical desulfating results. The battery needs time held at higher electrical pressure. They almost never get it, and this reduces their capacity and ability compared to a battery that does.
Originally Posted By: wrcsixeight
Battery Voltage is often seen as a gas tank fuel level gauge, but it is not.
A charger holding a battery at 13.3v seems like it is a smart charger at 'float' or maintenance voltage. It is either that or a very discharged battery that has not had enough time at the charger's maximum amperage output to yet rise above 13.3v
Generally there are 3 stages of chargeing.
Bulk is when the charger it outputting everything it can in order to reach the max voltage, called absorption voltage. Voltage will climb from whatever the battery is at to the mid 14v range
Absorption voltage is a constant voltage phase in the 14.4 to 14.7v range. How long the charger decide to hold absorption voltage is very important, and most will not hold it long enough, for fear of overcharging, and lawyers.
how long to actually hold absorption voltage will vary from battery to battery and will vary according to the depth of discharge, temperature, health, age. Ideal absorption duration is not something any smart charger is going to get right on each and every battery from each and every state of discharge.
When amperage tapers to a low level at absorption voltage then the battery is likely nearly fully charged, but no Smart chargers actually ask for the capacity of the battery to determine what level of amperage to end the absorption phase at. Most are just holding absorption voltage for X amount of time, and X was determined by some labcoat seeking some acceptable compromise, and then adjusted according to the beancounters and lawyers.
Float stage is Not designed to charge the battery, but to maintain it at full charge after it is been fully charged at absorption voltage. Charging will still occur of a 90% charged battery at float voltage, but it is very very slow, compared to if the battery were still being held at absorption voltage.
Those who believe the charger's green light indicating full charge, should dip a hydrometer when their charger flashes that green light, and usually will see the battery is well less than fully charged. OTC 4619.
Any voltage over the nominal full charge restnig voltage of that specific battery will charge the battery, but generally one wants voltage to climb to the mid 14's, remain there for a period of time before reverting to float voltage. Whenever one has the opportunity to plug in a charger, Ideally one wants the battery to be 100% full when it is unplugged. the 'trickle charge it overnight' recommendation seen far and wide is almost a joke in that this trickle chargers will usually require days to max out specific gravity, but it depends on the voltage the charger seeks and how many amps it has available to seek that absorption voltage. Any level of charging on an undercharged batter yis better than No charging of it, but the trickle charge recommendation should join the old wives in their insane asylum.
Any time a battery is charged it is being desulfated. It is when those sulfates have hardened, because the battery has sat for a period and gone through an extended period remaining less than fully charged, that the pulse desulfation chargers are said to do their magic breaking up the hardened sulfates and restoring plate material to the chemical reaction.
These pulse desulfating chargers have been tested on sulfated batteries in controlled settings by marine experts and found to do nothing than an extended time at absorption voltage could not do.
Pulse desulfating has become the battery charger marketer's favorite word to include on the packaging, as it works, the marketing, not the pulses.
Preventing a smart charger from dropping to float voltage prematurely on an undercharged battery can yield almost magical desulfating results. The battery needs time held at higher electrical pressure. They almost never get it, and this reduces their capacity and ability compared to a battery that does.
Interesting. I have a Noco G3500 (don't hate me), and it will charge my motorcycle AGM battery (on small AGM batt mode) rather quickly at .9A and will monitor it at 12.8V, but when I plug in my Truck's battery and put it on flooded/3.5A mode, it seems to never actually finish charging even after 12+ hours and holding the voltage at 13.3V or so, it still says it is not done charging. If I listen closely, I hear some slight popping/crackling from the battery case and assume I'm boiling my battery and I unplug it. I am not sure if I should trust it and leave it hooked up. What are your thoughts? My motorcycle battery is practically new while my truck battery is quite old. Perhaps the charger is just trying to do its job and I'm getting paranoid.
Battery Voltage is often seen as a gas tank fuel level gauge, but it is not.
A charger holding a battery at 13.3v seems like it is a smart charger at 'float' or maintenance voltage. It is either that or a very discharged battery that has not had enough time at the charger's maximum amperage output to yet rise above 13.3v
Generally there are 3 stages of chargeing.
Bulk is when the charger it outputting everything it can in order to reach the max voltage, called absorption voltage. Voltage will climb from whatever the battery is at to the mid 14v range
Absorption voltage is a constant voltage phase in the 14.4 to 14.7v range. How long the charger decide to hold absorption voltage is very important, and most will not hold it long enough, for fear of overcharging, and lawyers.
how long to actually hold absorption voltage will vary from battery to battery and will vary according to the depth of discharge, temperature, health, age. Ideal absorption duration is not something any smart charger is going to get right on each and every battery from each and every state of discharge.
When amperage tapers to a low level at absorption voltage then the battery is likely nearly fully charged, but no Smart chargers actually ask for the capacity of the battery to determine what level of amperage to end the absorption phase at. Most are just holding absorption voltage for X amount of time, and X was determined by some labcoat seeking some acceptable compromise, and then adjusted according to the beancounters and lawyers.
Float stage is Not designed to charge the battery, but to maintain it at full charge after it is been fully charged at absorption voltage. Charging will still occur of a 90% charged battery at float voltage, but it is very very slow, compared to if the battery were still being held at absorption voltage.
Those who believe the charger's green light indicating full charge, should dip a hydrometer when their charger flashes that green light, and usually will see the battery is well less than fully charged. OTC 4619.
Any voltage over the nominal full charge restnig voltage of that specific battery will charge the battery, but generally one wants voltage to climb to the mid 14's, remain there for a period of time before reverting to float voltage. Whenever one has the opportunity to plug in a charger, Ideally one wants the battery to be 100% full when it is unplugged. the 'trickle charge it overnight' recommendation seen far and wide is almost a joke in that this trickle chargers will usually require days to max out specific gravity, but it depends on the voltage the charger seeks and how many amps it has available to seek that absorption voltage. Any level of charging on an undercharged batter yis better than No charging of it, but the trickle charge recommendation should join the old wives in their insane asylum.
Any time a battery is charged it is being desulfated. It is when those sulfates have hardened, because the battery has sat for a period and gone through an extended period remaining less than fully charged, that the pulse desulfation chargers are said to do their magic breaking up the hardened sulfates and restoring plate material to the chemical reaction.
These pulse desulfating chargers have been tested on sulfated batteries in controlled settings by marine experts and found to do nothing than an extended time at absorption voltage could not do.
Pulse desulfating has become the battery charger marketer's favorite word to include on the packaging, as it works, the marketing, not the pulses.
Preventing a smart charger from dropping to float voltage prematurely on an undercharged battery can yield almost magical desulfating results. The battery needs time held at higher electrical pressure. They almost never get it, and this reduces their capacity and ability compared to a battery that does.
Interesting. I have a Noco G3500 (don't hate me), and it will charge my motorcycle AGM battery (on small AGM batt mode) rather quickly at .9A and will monitor it at 12.8V, but when I plug in my Truck's battery and put it on flooded/3.5A mode, it seems to never actually finish charging even after 12+ hours and holding the voltage at 13.3V or so, it still says it is not done charging. If I listen closely, I hear some slight popping/crackling from the battery case and assume I'm boiling my battery and I unplug it. I am not sure if I should trust it and leave it hooked up. What are your thoughts? My motorcycle battery is practically new while my truck battery is quite old. Perhaps the charger is just trying to do its job and I'm getting paranoid.
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I had a bad battery in the Rat. I often used a jump box for a cold start. The alternator was noticeably louder trying to charge a battery with a dead cell. It puts out 14.5 V up on fast idle. Should I be checking the water level? New battery, but.. The 90A Bosch in my BMWs was regulated to 14.1 V. The regulator also had the brush pack in it I've gotten 350K out of the alternator and a couple regs.They didn't over heat so innards lasted.
Originally Posted By: ThunderOne
.. but when I plug in my Truck's battery and put it on flooded/3.5A mode, it seems to never actually finish charging even after 12+ hours and holding the voltage at 13.3V or so, it still says it is not done charging. If I listen closely, I hear some slight popping/crackling from the battery case and assume I'm boiling my battery and I unplug it. I am not sure if I should trust it and leave it hooked up..
Leave it. Although, seems the charger is simply underrated.
.. but when I plug in my Truck's battery and put it on flooded/3.5A mode, it seems to never actually finish charging even after 12+ hours and holding the voltage at 13.3V or so, it still says it is not done charging. If I listen closely, I hear some slight popping/crackling from the battery case and assume I'm boiling my battery and I unplug it. I am not sure if I should trust it and leave it hooked up..
Leave it. Although, seems the charger is simply underrated.
When a smart charger is hooked to a battery that is up in the 12.65 or higher range, it seems to think the battery is close to fully charged,, and can instantly goto float stage, despite the battery being well below 100%.
One mmust outsmart the smmart charger.. Load the battery until voltage falls to the 12.5 or less range.
The charger should then seek 14.x volts with its mmaximum output.
Those with flooded batteries, with removable caps, can take hydrometer readings, See SG's in the fair to poor range, yet the charger will say all is fine and dandy, and throw that green light and hold float voltages, low 13's.
Very little pressure difference between 12.8 and 13.2. very few amps flow.
When the charger is trying to get the battery to 14.7, much bigger pressure difference, more amps flow, and that extra pressure can be required, not just to save time, but to reexpand the battery capacity back to its remaining potential.
One will never return a used battery to its max remaining capacity at float voltage.
Load the battery with something that can drag voltage to sub12,5v quickly, restart charger, remove load. Pray voltage at battery terminals climbs to 14.5ish volts and stays there for an hour or 4.
The battery state of charge Polygraph is the temperature compensated hydrometer.
When one uses one of these on a questionable battery, and one uses this trick the charger into doibng its job, by loading battery, restarting charger and forcing it to seek absorption voltage, one will likely see the specific gravity rise a bit more each time, upto the 1.275 range.
Note 1.275 specific gravity is not 12.75 volts and batteries in cold climates might go as high as 13.100 and those for intended for hot climates might only reach 1.265.
Trick your charger into doing its job. Load battery, drop voltage below 12.6, restart charger, let it go.
Lather rinse repeat until specific gravity no longer rises in response to time at 14.5ish volts.
the time it takes fore Sg to max out at 14.5v can be 2 hours, the time it can take for it to do it at 13.3 volts can be 5 days, or very possibly never.
Each and every lead acid battery since the beginning of lead acid batteries has always wanted to be 100% charged, and kept cool. Thge tool for determining 100% state of charge is bnot the green light on the smart charger. Their pootential to fully charge a battery was castrated at the factory for fear of overcharging. Like battery bubblewrap for helicopter parents.
That said any charging is better than no charging, just know 100% charged is not determined by a green light, no matter how impressive the marketing material is written, ,along with their 8 to 33 stages of charging, the last of which fellates the purchaser once the battery got its green light happy ending.
One mmust outsmart the smmart charger.. Load the battery until voltage falls to the 12.5 or less range.
The charger should then seek 14.x volts with its mmaximum output.
Those with flooded batteries, with removable caps, can take hydrometer readings, See SG's in the fair to poor range, yet the charger will say all is fine and dandy, and throw that green light and hold float voltages, low 13's.
Very little pressure difference between 12.8 and 13.2. very few amps flow.
When the charger is trying to get the battery to 14.7, much bigger pressure difference, more amps flow, and that extra pressure can be required, not just to save time, but to reexpand the battery capacity back to its remaining potential.
One will never return a used battery to its max remaining capacity at float voltage.
Load the battery with something that can drag voltage to sub12,5v quickly, restart charger, remove load. Pray voltage at battery terminals climbs to 14.5ish volts and stays there for an hour or 4.
The battery state of charge Polygraph is the temperature compensated hydrometer.
When one uses one of these on a questionable battery, and one uses this trick the charger into doibng its job, by loading battery, restarting charger and forcing it to seek absorption voltage, one will likely see the specific gravity rise a bit more each time, upto the 1.275 range.
Note 1.275 specific gravity is not 12.75 volts and batteries in cold climates might go as high as 13.100 and those for intended for hot climates might only reach 1.265.
Trick your charger into doing its job. Load battery, drop voltage below 12.6, restart charger, let it go.
Lather rinse repeat until specific gravity no longer rises in response to time at 14.5ish volts.
the time it takes fore Sg to max out at 14.5v can be 2 hours, the time it can take for it to do it at 13.3 volts can be 5 days, or very possibly never.
Each and every lead acid battery since the beginning of lead acid batteries has always wanted to be 100% charged, and kept cool. Thge tool for determining 100% state of charge is bnot the green light on the smart charger. Their pootential to fully charge a battery was castrated at the factory for fear of overcharging. Like battery bubblewrap for helicopter parents.
That said any charging is better than no charging, just know 100% charged is not determined by a green light, no matter how impressive the marketing material is written, ,along with their 8 to 33 stages of charging, the last of which fellates the purchaser once the battery got its green light happy ending.
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