Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 17-01-2017, 19:49   #1
Registered User
 
WizardOfTheWind's Avatar

Join Date: Sep 2016
Location: Brisbane, Australia
Boat: Jeanneau 45DS
Posts: 10
Battery Charging and Readings

We currently have 3 x 150Ah Lifeline batteries (currently being upgraded to 750Ah), a 40Amp Sterling Power Charge Ultra charger (another 40Amp about to be added in parallel for a total of 80Amp), a 240V Yamaha 2KVa generator, 2 x 200W solars and an Enerdrive ePro battery monitor. The boat is a Catalina 42 MkII, which we bought 6 months ago, and the main power drains have been the fridge (5A) and the freezer (6A). Because we have been experiencing quite hot weather here on the east coast of Australia, we have reduced both the fridge and the freezer to what we believe is the minimum already. We have LEDs throughout the boat and there are no other regular power hogs.

The batteries and the charger are being upgraded because of the substantial drop in battery state we have been noticing when we are on the hook for several days. Recently we had a number of days where the solars could not kick in, due to cloud cover, and we were dropping about 25%-30% overnight. Unless we use the engine (60A alternator) to get the batteries up to about 80-90%, the generator simply could not get the charge to a reasonable state, in several hours running, to avoid the batteries going below 50%. Obviously we prefer not to have to run either the generator or the engine for any length of time.

However, recently I have noticed that when we are hooked up to shore power the battery voltage does not go much past the float (13.2V), usually about 13.3-13.4, but when we are on engine power we see about 14.4V on the battery monitor.

I am hoping to get some feedback on the best power management procedure (engine, generator, solar) for those conditions but also whether I am likely to be looking at some other issue regarding the inability to reach boost voltage on shore power but seemingly able to do so on engine power. We have considered that the battery monitor may not be reading correctly but that does not seem to be the case. Am I missing something here?
__________________
David MacKinnon
Jeanneau 45DS #193
Brisbane, Australia
WizardOfTheWind is offline   Reply With Quote
Old 17-01-2017, 23:00   #2
Registered User

Join Date: Jan 2012
Location: vessel sold at LAKES ENTRANCE to a local. Currently nursing my 93 Y/o mother in Sydney. Next boat probably will be bought in the U.S.
Boat: triton 721 24' x 9' 1985 Cutter rigged.
Posts: 922
Re: Battery Charging and Readings

Wizard, for what it's worth I've been on the hook 27x7 for 7 years. Factor in that I've been a qualified mechanic and auto electrician here in Oz for many decades.
I have 480ah of AGM. My charger is a Pro Ultra 12/60. My generator is not a Yam but an inferior Ryobi. However, it starts, is quiet and it only stops when I turn it off.
My freezer is an Engel 38 litre and it runs about 12 hours a day pulling 2.75 amps. But with start-up spike I round the load to 3 amps times 12 hours = about 40 amp hours. And I watch TV about 6 to ten hours a day @ 5 amps pull = about 50 amp hours.
Because I love my batteries I never let the SOC get below about 70%.
I have a NASA monitor which is mounted but I never bothered to connect it, don't need to know what it thinks. My only guide to battery condition is how many volts are showing on the Blue Sea Systems analogue gauge when the freezer is pulling its' 3 amps.
All of that means that EVERY DAY I run my generator until the Sterling charger cuts back to 2.2 amps of float charge ( two point two amps).
The gen runs for at least two hours a day.....don't care. It's the price I have to pay for all the free to air channels and 40kg of great food.
Also, the 135 watt solar panel helps a bit.
Of course, when underway, the auto pilot and plotter etc are using juice also. About 10 days ago I left Sydney and am presently in Eden waiting 'til I've renewed all the standing rigging in prep for a Bass Strait crossing.
I believe.......especially as you have shore power, that you should forget about readings. That's what the charger is for, not your problem.
When on the hook, sure, read your volt meter and with your system pulling appreciable juice, when you voltage is reading about 12.4 or 12.5 volts...run the generator until the Sterling cuts back to float. You've plenty of solar to help with the loads but really, experience will likely show that you need to run the gen possibly every day.
Frankly, even with the wonderful Lifelines you have, in my opinion you should NOT be letting you loaded voltage get down to 12.2 as is often recommended.
There are many here who will opine re SOC desires. Up to you. But I care about my batteries too much to ever let them get to 12.2.
Anyway, good luck, you seem to have a good system in place but really, I would be ignoring the monitor and go to charge when the voltages fall to 12.4 to 12.5. Fully charged, with no current input is 12.8 which you likely know.
Actually, with solar being latitude and cloud cover/season dependent I suspect that you could well be charging every other day.
Good luck, if you want to chat just send me a PM and I'll send my Mob #.
Cheers.......if I ranted then forgive me please...merely keen to be of service.
brianlara 3 is offline   Reply With Quote
Old 17-01-2017, 23:53   #3
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Battery Charging and Readings

A couple of tips:

1. A battery monitor of that type will NOT tell you % state of charge with any reliability, and especially not if it hasn't been synchronized, and corrected for real battery capacity. You can improve the way it works, but for the time being, the best thing is just to ignore that particular readout.

2. Don't add new batteries to old batteries in the same bank. Batteries in the same bank need to be pretty close to the same age and condition, to work properly.

3. How old are the existing ones? Do you understand anything about their condition? The battery charger going to float prematurely is a sign of sulphated batteries -- sulphated plates will achieve a surface charge quickly, but that's all. I don't have experience with AGM batteries, but AFAIK you can't equalize them, so if they are sulphated, time to bin them. I would just bet that this is your problem.

4. Don't let the batteries get below 50%. How do you know, you may ask, if the battery monitor can't be trusted? The answer is system voltage. See your Lifeline manual for the table of SOC vs open circuit voltage. 75% is 12.5V and 50% is 12.2V. "Open circuit voltage" is difficult to measure, as it requires the batteries to rest for some time with no loads and no charging. But if you measure the voltage when there has been no charging for at least an hour or two, and no loads other than minimal system loads, for a while, you will be close. And best of all -- any error will be harmless -- will tend to understate the real SOC of the batteries.

You can also buy a SmartGauge, which is a superior type of battery monitor, which will give you extremely accurate SOC during discharge (doesn't work well while charging, however).

5. If your batteries are in reasonable condition (which I doubt), then there is something wrong with your charger. I would start with being sure that it is connected properly.


This doesn't cover everything, but should give you something to start with. With some luck, CF's REAL battery guru, MaineSail, will show up and give you some more qualified help. Good luck.
Dockhead is offline   Reply With Quote
Old 18-01-2017, 00:26   #4
Registered User
 
WizardOfTheWind's Avatar

Join Date: Sep 2016
Location: Brisbane, Australia
Boat: Jeanneau 45DS
Posts: 10
Re: Battery Charging and Readings

Quote:
Originally Posted by Dockhead View Post
A couple of tips:

1. A battery monitor of that type will NOT tell you % state of charge with any reliability, and especially not if it hasn't been synchronized, and corrected for real battery capacity. You can improve the way it works, but for the time being, the best thing is just to ignore that particular readout.

2. Don't add new batteries to old batteries in the same bank. Batteries in the same bank need to be pretty close to the same age and condition, to work properly.

3. How old are the existing ones? Do you understand anything about their condition? The battery charger going to float prematurely is a sign of sulphated batteries -- sulphated plates will achieve a surface charge quickly, but that's all. I don't have experience with AGM batteries, but AFAIK you can't equalize them, so if they are sulphated, time to bin them. I would just bet that this is your problem.

4. Don't let the batteries get below 50%. How do you know, you may ask, if the battery monitor can't be trusted? The answer is system voltage. See your Lifeline manual for the table of SOC vs open circuit voltage. 75% is 12.5V and 50% is 12.2V. "Open circuit voltage" is difficult to measure, as it requires the batteries to rest for some time with no loads and no charging. But if you measure the voltage when there has been no charging for at least an hour or two, and no loads other than minimal system loads, for a while, you will be close. And best of all -- any error will be harmless -- will tend to understate the real SOC of the batteries.

You can also buy a SmartGauge, which is a superior type of battery monitor, which will give you extremely accurate SOC during discharge (doesn't work well while charging, however).

5. If your batteries are in reasonable condition (which I doubt), then there is something wrong with your charger. I would start with being sure that it is connected properly.


This doesn't cover everything, but should give you something to start with. With some luck, CF's REAL battery guru, MaineSail, will show up and give you some more qualified help. Good luck.
Hi Dockhead,

Many thanks for the reply

1. Yes, I realise that the battery monitor may not be reading correctly, which may be causing some, or all, of the problem. It has been synchronised several times over the last few weeks so that should not be an issue.

2. The current batteries are 2 years old.

4. I never let my batteries go below 50% but, as you have highlighted, the monitor may not be accurate so I have been making sure that the voltage does not get to 12.2V. As per your suggestion, I will look at ensuring that there is no charging for an hour or two and see what I get then.

5. I believe that the batteries are actually in quite good condition but I do have some concerns as to whether the charger is correct. Because of the difference in voltage between stationary shore power and running on the engine alternator I do have some concerns as well about the current setup.
__________________
David MacKinnon
Jeanneau 45DS #193
Brisbane, Australia
WizardOfTheWind is offline   Reply With Quote
Old 18-01-2017, 04:39   #5
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Battery Charging and Readings

Quote:
Originally Posted by WizardOfTheWind View Post
Hi Dockhead,

Many thanks for the reply

1. Yes, I realise that the battery monitor may not be reading correctly, which may be causing some, or all, of the problem. It has been synchronised several times over the last few weeks so that should not be an issue.

2. The current batteries are 2 years old.

4. I never let my batteries go below 50% but, as you have highlighted, the monitor may not be accurate so I have been making sure that the voltage does not get to 12.2V. As per your suggestion, I will look at ensuring that there is no charging for an hour or two and see what I get then.

5. I believe that the batteries are actually in quite good condition but I do have some concerns as to whether the charger is correct. Because of the difference in voltage between stationary shore power and running on the engine alternator I do have some concerns as well about the current setup.
OK. Some further comments:

1. Synchronization of the battery monitor won't really help, if it has the wrong idea about the real capacity of the bank, and in general getting SOC out of amps run out of the bank is a very iffy proposition. I would suggest watching voltage. If you don't allow the voltage to fall below 12.2V under light loads, then you can be sure you are not getting below 50% -- that's pretty foolproof, unlike the amp-counting battery monitor WHOSE ERROR IS ALWAYS ON THE WRONG -- DANGEROUS -- SIDE.

2. Difference between charging behavior between alternator and charger is meaningless. They are regulated in different ways. There are different reasons why the alternator may be force-charging the batteries even though they are actually full.

3. Incidentally, if your alternator is not externally regulated, this is the FIRST place I would invest in your system. Read MaineSail's site on this and other charging and batteries issues.

4. The fact that the batteries are only two years old, doesn't really tell you whether they are in good condition or not. You can ruin a set of batteries in a week. I would suggest doing a capacity test on them before blaming your charger. See: http://batteryuniversity.com/learn/a...sure_capacity; but the most realistic way to do it is to put a load on it and run it down.

5. If your batts pass the capacity test, then check the charger installation -- wired correctly, good connections, proper gauge wiring, etc.

6. If that checks out, then buy a different charger -- don't just add and parallel a second one. Sell the old one (or bin it, if it is defective).

7. Said before but worth repeating -- don't add new batteries to a bank of old ones. Get rid of the old ones -- sell them if they are still usable. Batteries combined in a single bank must be well matched.


Good luck, and let us know how you get on!
Dockhead is offline   Reply With Quote
Old 18-01-2017, 10:41   #6
Registered User

Join Date: Oct 2007
Location: North Carolina
Boat: Hunter 54
Posts: 126
Re: Battery Charging and Readings

Quote:
Originally Posted by Dockhead View Post
OK. Some further comments:


7. Said before but worth repeating -- don't add new batteries to a bank of old ones. Get rid of the old ones -- sell them if they are still usable. Batteries combined in a single bank must be well matched.


Good luck, and let us know how you get on!
I understand the "weak link" issues when old and new batteries are connected in series but not so clear when they are connected in parallel. Lets say we have two house banks and both deliver the same ampere hours on a capacity test. Bank #1 has four new batteries in parallel that are matched. Bank #2 has two new batteries and three older batteries in parallel. Ignoring the lighter weight advantage of bank #1 why do you say bank #2 is not good? Would it not make sense to perform a capacity test on individual batteries and replace the ones that measure less than say 50% ?
Thanks
Ahmet Erkan is offline   Reply With Quote
Old 18-01-2017, 12:20   #7
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Battery Charging and Readings

Quote:
Originally Posted by Ahmet Erkan View Post
I understand the "weak link" issues when old and new batteries are connected in series but not so clear when they are connected in parallel. Lets say we have two house banks and both deliver the same ampere hours on a capacity test. Bank #1 has four new batteries in parallel that are matched. Bank #2 has two new batteries and three older batteries in parallel. Ignoring the lighter weight advantage of bank #1 why do you say bank #2 is not good? Would it not make sense to perform a capacity test on individual batteries and replace the ones that measure less than say 50% ?
Thanks
From the Lifeline manual:

"Multiple Batteries:

If there is more than one battery in the battery bank, the following guidelines should be used:
• Always use batteries of identical make, model and with the same manufacturing date. "

http://www.optimabatteries.nl/upl_fi...r%20manual.pdf


Doesn't matter whether they are connected in series or parallel, one weak battery will throw off the whole bank. It is important that all batteries in a single bank are same age and condition.

"We would strongly discourage anyone from connecting batteries in series or parallel applications, if the batteries are not identical in age, size and type.

When you connect two or more batteries that don't charge and discharge at the same rate, one battery will probably end up overcharged and/or one battery will end up undercharged. Neither is a scenario you want to have happen to your batteries, as it will probably shorten the lifespan of both and could create a potentially create a dangerous situation, if one battery gets severely overcharged.

The same is also true of batteries that are identical in every way, except that one battery is older than the other. As batteries age (or get used), their charge/discharge profile changes. As such, they essentially charge and discharge at a different rate a year later, than they did when they were brand-new. That means you shouldn't connect batteries together that aren't the same age or haven't been used in the same application since they were new, even if they are the exact same make and model.

Unfortunately, that means when one battery in a bank of two or more batteries needs to be replaced, they should all be replaced at the same time. That doesn't mean the other functioning batteries should be discarded entirely, but they should not be used in an application that has batteries that differ in age, size or type. For some marine and RV applications that use a lot of batteries, it may make sense to isolate a larger bank of nine batteries into three smaller banks of three batteries, instead of connecting them all together. That way, if one battery goes bad, far fewer batteries need to be replaced."


https://www.optimabatteries.com/en-u...eries-parallel


It is also important to connect them with equal lengths of cabling of equal size. Here's a good resource: SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank
Dockhead is offline   Reply With Quote
Old 18-01-2017, 14:40   #8
Registered User

Join Date: Mar 2011
Location: fl- various marinas
Boat: morgan O/I 33' sloop
Posts: 1,447
Re: Battery Charging and Readings

Quote:
Originally Posted by WizardOfTheWind View Post
We currently have 3 x 150Ah Lifeline batteries (currently being upgraded to 750Ah), a 40Amp Sterling Power Charge Ultra charger (another 40Amp about to be added in parallel for a total of 80Amp), a 240V Yamaha 2KVa generator, 2 x 200W solars and an Enerdrive ePro battery monitor. The boat is a Catalina 42 MkII, which we bought 6 months ago, and the main power drains have been the fridge (5A) and the freezer (6A). Because we have been experiencing quite hot weather here on the east coast of Australia, we have reduced both the fridge and the freezer to what we believe is the minimum already. We have LEDs throughout the boat and there are no other regular power hogs.

The batteries and the charger are being upgraded because of the substantial drop in battery state we have been noticing when we are on the hook for several days. Recently we had a number of days where the solars could not kick in, due to cloud cover, and we were dropping about 25%-30% overnight. Unless we use the engine (60A alternator) to get the batteries up to about 80-90%, the generator simply could not get the charge to a reasonable state, in several hours running, to avoid the batteries going below 50%. Obviously we prefer not to have to run either the generator or the engine for any length of time.

However, recently I have noticed that when we are hooked up to shore power the battery voltage does not go much past the float (13.2V), usually about 13.3-13.4, but when we are on engine power we see about 14.4V on the battery monitor.

I am hoping to get some feedback on the best power management procedure (engine, generator, solar) for those conditions but also whether I am likely to be looking at some other issue regarding the inability to reach boost voltage on shore power but seemingly able to do so on engine power. We have considered that the battery monitor may not be reading correctly but that does not seem to be the case. Am I missing something here?
Before buying anything else you might look into a larger generator. 2KV is rather small for a boat like yours. That might be the key to coping with cloud cover when on the hook. I see nothing to indicate why a second charger is needed. Your failure to see 14+ on shore power could be simply that the first stage does not last very long. It's easy to miss. If you are showing 13.2-.4 I would not worry about it. You can settle your doubts by turning off your charger until you see 12.5 or so and then watching the volts after you turn it on. That might give you a feel for how long the boost stage lasts. Are you seeing boost voltage only after anchoring a while or whenever the engine is running. If the latter, I would call in an electrician soonest. You absolutely do not want to overcharge your batteries.
Dave22q is offline   Reply With Quote
Old 18-01-2017, 19:12   #9
Registered User

Join Date: Dec 2014
Location: the Med
Boat: Nauta 54' by Scott Kaufman/S&S - 1989
Posts: 1,180
Images: 3
Re: Battery Charging and Readings

I positively decided to live without a battery monitor (or 3, having 3 banks).

I read the Volt-meter and the A charging.
Boat life turns around battery mgmt all the day round, honestly... so I added solar
TheThunderbird is offline   Reply With Quote
Old 18-01-2017, 22:58   #10
cruiser

Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
Re: Battery Charging and Readings

Quote:
Originally Posted by WizardOfTheWind View Post
........... . Unless we use the engine (60A alternator) to get the batteries up to about 80-90%, the generator simply could not get the charge to a reasonable state,.....
However, recently I have noticed that when we are hooked up to shore power the battery voltage does not go much past the float (13.2V), usually about 13.3-13.4, but when we are on engine power we see about 14.4V on the battery monitor.
..........
Sounds like maybe something is up with the pro charge ultra?
What battery type is it set to & how many amps does it say are going out when it's turned on?

Good resource here but only if you pay for it..
https://www.morganscloud.com/series/...n-maintenance/
conachair is offline   Reply With Quote
Old 18-01-2017, 23:52   #11
Marine Service Provider
 
mitiempo's Avatar

Join Date: Sep 2008
Location: Victoria B.C.
Boat: Wauquiez Centurion 32
Posts: 2,874
Re: Battery Charging and Readings

Quote:
Originally Posted by Dockhead View Post
I don't have experience with AGM batteries, but AFAIK you can't equalize them, so if they are sulphated, time to bin them. I would just bet that this is your problem.
Lifeline Agm batteries can and should be equalized. Lifeline are the only Agm manufacturer that recommends this.

I agree sulfation is likely the problem.
mitiempo is offline   Reply With Quote
Old 19-01-2017, 14:01   #12
Registered User
 
01kiwijohn's Avatar

Join Date: Mar 2014
Location: Tacoma, Washington, USA
Boat: Casacde 36
Posts: 596
Images: 1
Re: Battery Charging and Readings

Ref your penultimate para;
Dockside, you may be ok there. Trojan recommends floating at 13.5 to 13.8V. You're a little low, but not by much. It may be that the instrument shows Bulk charge, for a very short period, then goes into float, which you are seeing.
Running, at 14.2V is normally what you expect to see after start up, as that is the regulator setting for most engine alternators.
I'd be inclined to check the batteries with an old fashioned Hydrometer. An SG of 1275 is full charge. Disconnect the batteries and let them sit for, say, 12 hours, then compare with your other instruments before you go replacing stuff. Don't fix what ain't broke.
01kiwijohn is offline   Reply With Quote
Old 19-01-2017, 16:59   #13
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Battery Charging and Readings

Quote:
Originally Posted by 01kiwijohn View Post
. . .
I'd be inclined to check the batteries with an old fashioned Hydrometer. . . .
He's got AGM batteries. Hydrometer doesn't work too well with those . . .
Dockhead is offline   Reply With Quote
Old 19-01-2017, 17:00   #14
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Battery Charging and Readings

Quote:
Originally Posted by mitiempo View Post
Lifeline Agm batteries can and should be equalized. Lifeline are the only Agm manufacturer that recommends this.

I agree sulfation is likely the problem.
I didn't know any AGM batts could be equalized. That's cool to know. The OP should do a couple of rounds of deep discharge followed by equalization and see if that helps.
Dockhead is offline   Reply With Quote
Old 20-01-2017, 16:18   #15
Registered User

Join Date: Oct 2007
Location: North Carolina
Boat: Hunter 54
Posts: 126
Re: Battery Charging and Readings

Quote:
Originally Posted by Dockhead View Post
From the Lifeline manual:

"Multiple Batteries:

If there is more than one battery in the battery bank, the following guidelines should be used:
• Always use batteries of identical make, model and with the same manufacturing date. "

http://www.optimabatteries.nl/upl_fi...r%20manual.pdf


Doesn't matter whether they are connected in series or parallel, one weak battery will throw off the whole bank. It is important that all batteries in a single bank are same age and condition.

"We would strongly discourage anyone from connecting batteries in series or parallel applications, if the batteries are not identical in age, size and type.

When you connect two or more batteries that don't charge and discharge at the same rate, one battery will probably end up overcharged and/or one battery will end up undercharged. Neither is a scenario you want to have happen to your batteries, as it will probably shorten the lifespan of both and could create a potentially create a dangerous situation, if one battery gets severely overcharged.

The same is also true of batteries that are identical in every way, except that one battery is older than the other. As batteries age (or get used), their charge/discharge profile changes. As such, they essentially charge and discharge at a different rate a year later, than they did when they were brand-new. That means you shouldn't connect batteries together that aren't the same age or haven't been used in the same application since they were new, even if they are the exact same make and model.

Unfortunately, that means when one battery in a bank of two or more batteries needs to be replaced, they should all be replaced at the same time. That doesn't mean the other functioning batteries should be discarded entirely, but they should not be used in an application that has batteries that differ in age, size or type. For some marine and RV applications that use a lot of batteries, it may make sense to isolate a larger bank of nine batteries into three smaller banks of three batteries, instead of connecting them all together. That way, if one battery goes bad, far fewer batteries need to be replaced."


https://www.optimabatteries.com/en-u...eries-parallel


It is also important to connect them with equal lengths of cabling of equal size. Here's a good resource: SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank
Basic theory as well as common sense tells me it does make a difference whether cells are connected in parallel or in series but this was not my question anyway. My question again, worded slightly differently was, if a cruiser chooses to perform a capacity test on the individual 12V or 6V batteries that are part of the battery bank and replace only the ones that fail the test, why is this practice so bad? What if you left a battery that measures at only 10% of its nominal capacity connected in the parallel bank as long as it is fused and temperature is monitored? Even the new batteries in parallel should be fused and temperature monitored anyway.
About the subject of using only equal length cables etc to parallel batteries the recommended article is partially true. Batteries in parallel will self equalize during both discharge and charge cycles and self compensate for small imbalances in the wiring resistance and/or mechanical layout. If the forum is interested I can use the same numbers in the example in the article recommended by Dockhead by using a more realistic analysis.
Look, I am not trying to prove anybody wrong here, but I am not going to take articles written by marketing departments of manufacturers as proof of laws of physics. After all the battery manufacturers want their customers to replace all their batteries even if only one of them needs to be replaced.
Bottom line :
Yes I will continue to connect both old and new as well as different capacity and different manufacturers batteries in parallel as long as the specified float voltage is compatible and the batteries use the same technology. (ie: FLA, AGM etc) If anybody is pontificating "what if one battery gets overcharged" etc explain the mechanism that makes you so sure it could happen and I will be the first one who listens.
Ahmet Erkan is offline   Reply With Quote
Reply

Tags
battery, charging

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
charging a small battery from a larger battery danielb Electrical: Batteries, Generators & Solar 15 26-01-2015 17:22
Battery Charging, Battery Return amps and Victron inthejungle Marine Electronics 2 16-09-2013 12:36
Battery Charge Readings ? sailorboy1 Electrical: Batteries, Generators & Solar 82 02-04-2013 08:52
Depthsounder Readings gbendaly Marine Electronics 2 08-11-2009 15:11
Readings from Instruments while Engine Off marno Electrical: Batteries, Generators & Solar 2 27-09-2009 09:56

Advertise Here


All times are GMT -7. The time now is 04:26.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.