Batteries not Charging all the way

[jmacstack]

Jennifer here, once again,
While I was out this weekend, I was unable to plug in,(more on that in a second) and had to run my generator, (20KW.) I had to run it a lot of hours a day to get a mere 12.4 volts. An hour later my gauge on the interior panel was back to 12 volts. When the generator was running the gauge was reading 13.4. I drove 3.5 hours each way to my destination and upon arrival, the gauge was at also at 12.4. (I drove without the generator running.) While parked and with the generator was running I was pulling 20+amps and I assume it was because the battery charger was running. When the generator was not running I was drawing about a half to 1 amp on both legs. The batteries are new 1 year ago. The battery charger is new and has maybe 10 hours on it. It is a "smart" charger (progressive dynamics I think.) I spent the entire weekend watching the gauge and stressing that the batteries were going to dip below 12. I'm wondering if it is the gauge or if there was something else happening. Tomorrow I am going to plug into 50 amps for the day and see what happens.

Separate issue perhaps...
I tried to plug in at the fairgrounds I was camped at and they only had 20 amp breakers. This fairground panel has 200 amps servicing it. There were probably 30 pedestals in a row and I was near the end of the line. No one else was plugged into these hook-ups. The breaker in the fairgrounds panel kept tripping. I assumed that it was because the 20 amp was on such a long run, there was too much resistance and the breaker couldn't handle it. I even turned off every breaker in the panel hoping that might solve the issue...no luck. I also changed to a different outlet and that didn't help. Perhaps this is related to my charging issue. I have had to plug into 20 amps recently and all went well. According to the electrical panel at the fairgrounds, each pedestal had its own breaker. When I tripped the breaker it would last for anywhere from 10 minutes to 20 minutes before it tripped. Again, I would draw the 20+amps and again, figured it was the charger. Am I right to think the breaker was tripping due to the long run or could it be something else? Are these issues related? Any clues as to who is the best person to help me figure this out if I can't? I know there probably a lot of questions to get to the bottom of this and perhaps a phone call might be better. Electrical issues can be a bit of a nightmare. Perplexed, Jennifer

[chockwald]

Have you checked the water level in the batteries.......I'm assuming they are "wet" batteries?

[fulltiming]

Clarke's idea is a good starting place. If you have lost much of the water in a cell or battery it could cause the charger to run like crazy trying to recharge it. A dead cell in one battery could also cause an extra draw on your charger. After checking the level of the water in each cell, refilling any that are low, recharge the batteries, then disconnect the batteries one at a time and measure their no low voltage. If one is significantly lower than the others, you may have a short or dead cell in that battery. Sometimes you can restore a battery if the plates have dried out but it will take patience recharging that one battery by itself for an extended time or if your charge supports equalization, that can sometimes bring back a dying battery.

[prairieschooner]

It most likely isn't your Batteries but you should start there, sounds like your Batteries were Charged at less than 75%. When troubleshooting I always start at one end, then the other end, then cut the circuit in half, then in half again, etc.
12.4 is very low Voltage for a 12 Volts DC System. If you have Wet Acid Batteries they should be Charged at 14.4 Volts DC, follow this link for more;
http://www.westmarine.com/webapp/wcs/stores/servlet/WestAdvisorView?langId=-1&storeId=11151&catalogId=10001&page=Battery-Charging

I would start by checking all of the Battery, Battery Switch and other Connections and making sure that the Cables are tight at every connection.
Now let's look at your Charging System with the Alternator. I suggest that you isolate the Engine Batteries (shut down the House Battery Switch and Battery Merge for this test). I would use a Digital Volt Meter and test the Voltage at the Alternator and then the Batteries. You should see 14.4 Volts DC when the Alternator is Fully Charging.
Not being sure about the Shore Charging System it is hard to advise. I like being able to use the Charging Function of our Heart Inverter (bought by Xantrex). It has a 100 Amp DC Output making getting to about 90% fairly fast, about an hour or less when we Dry-Camp, rule of thumb- use 50% of the Battery Capacity. Now if you have 240 Amp Hour Battery Bank you should only use about 120 Amps. If you have a 20 Amp Battery Charger it will take at least 6 hours to get the Batteries up to 90% Capacity.

*The Charging Systems for our House and Engine Batteries are completely Separate, and this is by my design. My Battery Merge Switch only allows the Engine System to Charge the House System if I Manually Select it to do that. I personally like to have my Charging Systems Separate but it isn't for everyone.

[encantotom]

a few rambling thoughts.

the question about the power at the fairgrounds......i would be very surprised that the problem was a result of a lengthy run. what a lengthy run does is lower the voltage and is called a voltage drop. shutting off the other breakers would not change anything. our coaches should run on 104-132v. i have the progressive industries power management system on my coach and that is the range of voltage it will "allow" into the coach before shutting it off. most 120v AC devices have a real wide tolerance of voltage operation just for the reason of the many variables that influence voltage in a residence.

what electricians do when wiring up long runs is to do a voltage drop calculation, or most do a rule of thumb of upping the wire size one size for each 100-200 feet. i said rule of thumb because it makes a difference of what starting voltage and what type of wire etc. standard 20a wiring is #12 wire. the indicators of a long run without increasing the wire size is lower voltage and the problem then should have been in your coach. of course, anything is possible.

given that you said it would trip after 10-20 minutes raises a few thoughts from my feeble mind. particularly since you said it didnt matter what pedestal you used at the fairgrounds. it is always a possiblity that the breakers were weak at the fairgrounds, but given that you tried several, that seems to be a low chance.

it seems more likely to me that something in your coach was kicking on periodically that was in conjunction with the other things your were using caused the coach to be drawing 20 amps or more, causing the 20a pedestal breaker to blow. the biggest culprits for current surges are anything with a motor. motors have typically 1.5-2.5x surges at startup (called LRA, locked rotor amps), that can cause amperage spikes. in particular, any type of compressor is the biggest culprit, like a fridge, air con, icemaker, etc. however any electric motor surges.

or anything that will cycle, like chargers, hot water heaters, etc.

all of this is only to do with the pedestal breaker popping. like is said, since there are so many variables, you could have found the perfect combination of things that made it unique to that fairgrounds, which is easy enough to tell if you plug in at another place and it works.

now a few comments about your batteries.

michael and clarke and steve had great comments. having made many battery mistakes in the past here is how i would start, and take it with a grain of salt and merge it with the other folk's comments. i would not rely on the meters in the coach for troubleshooting. get a handheld volt ohmeter if you do not have one. any cheap ol one will work. i have expensive ones and cheap ones. the cheap ones are fine for this. 3 bucks at harborfreight. or spend 20-250 bucks for a radioshack or fluke. start cheap unless you are going to use it a ton.

1. if the batteries have caps you can check the water on do so and add distilled water as necessary. as everyone knows, charging batteries with the plates exposed kills them quickly.

2. then charge them overnite. you can check the "smart charger" by monitoring the voltage at the batteries with a voltmeter. it will start out and progress through different voltages immediately after turning it on. you can see those voltages at the batteries with a voltmeter. get your manual out for your charger and it should tell you the times and voltages. that wasy you can make sure the charge is working right. most likely is, but it will help eliminate things. as elmination is the name of the game.

3. isolate the batteries as michael said and check voltages. in this case, make sure to isolate the batteries or you will be reading combined voltages. like was said before, if one battery is alot different than the other one, suspect it has a dead or shorted cell. these big ol 8D batteries are heavy, so it might be easier to drive the coach to a battery shop to have it load tested (with the batteries disconnected you are checking). btw, i bought my engine batteries at a sams club and they had a load tester capable of 8D batteries. i took the batteries there, but the batteries are a mere fraction of weight compared to me.....a bad cable connection can cause lots of problems. as part of isolating the batteries to test them, i would completely clean each cable end and battery lug or terminal. a bad ground or connection can cause lots of wierd problems.

4. on all of the coaches i have seen of our vintage, there is a huge fusible link on each battery bank. on mine, i thought my batteries for my starting side were bad, and it ended up that the fuse was bad. on mine and most others, it is on the ground and sits on top of the battery. it is about an 1.25" in diameter with flat connection lugs on each side of the cylinder. i would check that as well. isolate it and just check across with an ohmeter.

5. remember the voltmeters on your dash and overhead will display what is on the circuit. what i mean by that is if you are driving and your alternator is putting out 13.4v, that is what will be on the meter as long as the alternator can keep up with the demand. that is even if your batteries are at 12v, the meter will show what is coming out of the alternator within reason. same for being parked and engine off and charger on. with the charger off, engine off, then it will read the combined battery voltage and will go down as the batteries are drawn down.

6. after all of this, hopefully you found something simple. if not, and the batteries are good, the charger is good, the fuse is good etc.

7. if everything still checks out, then you have to start tracing from a good point forward a piece at a time. from the batteries up is where i would likely start.

of course, as usual like i said before, use what works for you.

and someone check my thoughts as i started this earlier than i like to get up.

later

tom

[prairieschooner]

what have you found?

[jmacstack]

When I left the coach on Sunday, I shut off all power to coach. Yesterday(Friday) when I checked my batteries, they were only 25% charged according to my battery tester(floating disc) this is after I drove for 3 hours on Sunday.

All cells full. All cables tight and clean. I am now plugged into 50 amps and have been for the last 15 hours. I will go and check charge status today. Charger is operating and have not checked output yet. I will know more today.

[encantotom]

so the batteries were totally charged when you dropped it off on sunday? what do you mean by shutting off all power to the coach? do you mean you used both battery bank shutoff switches in the back? or do you just mean that you turned everything off you know of inside?

if there is a current draw, it can draw the batteries down and you not even know it.

for example an 8d agm lifeline battery has 255 amp hours 475 min at 25a 825 min at 15a 1670 min at 8a

double that for two fully charged batteries.

just for funs sake....lets say you had left on 4 of the lower bay lights.

they draw i would guess about 2amps each for a total of 8amp draw.

if your batteries were at 25%, then 1670x2=3340x.75=2227minutes at 8amps. that is about 2 days of draw.

so if you were getting from sunday to friday (5 days) to get to 25%, then you are drawing 60x25x5=7500 minutes or using the data above, you were drawing about 3amps for 5 days to get 2 8d batteries down to 25%. that is not very much. like a couple of lights on somewhere you dont know about.

i did some estimation, but in general it is right.

i know it doesnt seem like it takes much to discharge the batteries and that is why if you run the icemaker on the inverter it will run my batteries down overnite.

and why the newer coaches have six 8D batteries just for the coach side to run the all electric coach when dry camping. that big electric fridge really draws the amps in DC when inverting to AC.

so, not saying this is the case for you, but an illustration of how quickly the coach batteries can run down if there are some devices of any kind left on.

later

tom

[jmacstack]

Tom. I shut down both battery bank main shutoff switches. I had driven the coach for 3.5 hours + to get home. Shut off both mains when I got here. Should the batteries have been fully charged after driving 3.5+ hours? Checked batteries 5 days later to start the trouble shooting process on Friday and they were at 25%. Will check them today. They have been charging for 2 days. I have lead acid batteries. Puzzling. Jennifer

[prairieschooner]

Jennifer,
It appears that something is drawing down the Batteries. Since you Shut down the Battery Switches and they still went down there could be something wired direct that is drawing power or simply a bad battery.
Sounded like you used a Hydrometer to test the Batteries, do you also have a Digital Volt Meter?
I would start with a simply approach. Charge the Batteries to a Full Charge with the Shore Battery Charger and then measure the Voltage and Specific Gravity. Physically disconnect and isolate all of the Batteries with the Ground Cables (much safer to keep from arc welding with the wrench). Now wait for a day or two and measure the Voltage and Specific Gravity again, the Voltage would signify a problem while the Hydrometer would describe the problem. Now you should know if the Batteries are in good condition or if something has been wired to bypass the Battery Switches.
If all is well there is a Clamp on DC Amp Meter that could help with trouble shooting a power drain. I want one but haven't had to buy one yet, a friend loaned me his and they are great. Here is a link;
http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=17537&catalogId=10001&langId=-1&storeId=11151&storeNum=10109&subdeptNum=10598&classNum=10600

[encantotom]

hi,

do you have the merge switch on? are we only talking about the coach batteries or the starting batteries or both?

it is hard to tel on how long it takes to charge a battery while driving. each battery has what is called an "acceptance rate", based on the total amp hours of the battery bank, the degree to which it is discharged and the type of battery it is. AGM's have a higher acceptance rate than wet cells.

having said all that and assumming you have a 160amp alternator or so, and you drove at day, they likely should have charged in 3-4 hours.

many folks run their genny's for a few hours each day to top off the coach charge when dry camping.

it is a simple thing, just hard to find.

1. a bad battery or
2. a bad connection or
3. a steady current draw you dont know about
4. or a bad charger. it would have to be both the charger and the alternator.

or a combination of the above.

i welcome anyone else to add in. i could be wrong about any of this....

tom

[Richard and Rhonda]

Hi Jennifer,

Are you using a hydrometer to determine level of charge or using the voltage?

I know all "technical" source books say to use a hydrometer. However, some of them are hard to properly read, and none of the cheaper ones are calibrated. They are extremely useful for locating a bad cell in a wet battery though.

What are the voltages when you say the batts are 25 and 75 percent charged?

[prairieschooner]

Sorry Richard but that isn't exactly correct and I beg to differ. If you use the same Hydrometer between all of the Battery Cells then even if it is an Inexpensive Tool it would at least someone would be able to be compare each Battery Cell and then compare all to help identify a bad Cell, not all tools need to be calibrated to be of value.
I still prefer a Volt Meter butt I believe that even an inexpensive hydrometer would be very valuable in trouble shooting this problem.

[jmacstack]

Today I went to the coach to further my investigation. I noticed the building was hot....it had been closed up all weekend. Then I noticed the engine compartment was hot...upon touching the engine it too was hot! I thought about it for a second and went inside to check the engine heater...it was running and probably has been all through the weekend I was out camping trying to not blow breakers at the fairgrounds. Time to put a piece of tape over that switch..it's by the bed in the back among a row of other switches...easy to hit by mistake. Now I know why I was blowing breakers at the fairgrounds. There was too much draw and every time the fridge kicked in it was to much for the breaker to handle.

I checked the batteries. I am still only floating 1 disc with my hydrometer. These are brand new batteries....or so they said. Now I'm feeling skeptical. I turned off the big inverter, engine heater switch is off. Tomorrow I will check the batteries with my volt meter and report back. The combined voltage of the batteries today was 13.22. I did not isolate the batteries and will do so tomorrow. Could that big 50amp(I think) flat fuse that the positive side of the batteries is connected to be bad? I can't remember what that flat fuse is called..is it the fusible link? I have an extra one. I will check it for continuity tomorrow. There is some corrosion on it. So that is the update..more tomorrow. Thanks you all for all your input, it is really helpful. Jennifer

[encantotom]

i figured there was something running that was drawing the batteries down.

the fuse i was referring to looks like this. it is probably 3 inches long.


SHAWMUT A3T600 600 AMP 300 VOL. A3T 600 FUSE CLASS T

this is the replacement i bought. i got a couple of them on ebay for 45 dollars or so apiece. closer to a hundred if you buy them retail.

tom

[Richard and Rhonda]

"They are extremely useful for locating a bad cell in a wet battery though."

Steve, I think you and I said the same thing. Even with the worst calibration, they can point out differences between cells. I stick by my statement that an uncalibrated one is marginally useful for determing % charge of a battery based upon the specific gravity. I can send you the three different ones I have purchased that give three totally different readings. Cept, they are not worth the cost of shipping them to you.

I snagged a typical chart off the net for 12v batteries. http://www.solar4power.com/solar-power-battery.html

It would seem to indicate if you are reading 13.22 then the batteries are charged.

[prairieschooner]

This has me wondering if the Inverter could have been left on allowing the Engine Block Heater to draw your Batteries down.
Anyway 13.2 Volts DC would signify a Charged 12 Volt Battery so at least the Charging System is functioning as long as that Voltage was taken with the Charger turned Off.
Our Engine Block Heater has a Light at the Switch inside, does yours? if not it would be a nice addition. Our AC Generator also has a Light near the Switch inside. I always unplug the Block Heater (at the Engine Compartment) because one of Dogs, Bonnie, likes to lay back there and frequently has turned the switch on.

[encantotom]

hi steve, you said something that has me wondering. my block heater is not hooked up to my inverter. is yours?

if it was her block heater, then it would have to be 110v then?

thanks

tom

[folivier]

Just a thought, but could that switch be a water tank heater instead? That could be 12volt.
Good luck.

[prairieschooner]

Tom,
I am not so sure that the Heart Inverter was original equipment for our '82. When we got the '82 the Power Inverter had been wired to the Switch Panel and all was able to be used, this is the easiest way to install one. Here I am trying to work on the AC Electrical System and it was still hot after I shut down the Main Circuit Breaker? and still hot after the Power Cord was removed?? I found the problem to be the way the Power Inverter was wired. This was corrected right away but there is no telling what a PO may have done.
I added a Selector Switch (Marine Grade of course) to the AC Switch Panel. Only the two Televisions and the Microwave Oven can be powered with the Heart Power Inverter. By the way we also have a Powerline Inverter (the kind that the Truckers use) that powers up our Ice-maker. I like how the original owner was thinking, cocktails on time even after driving all day!
By the way guys this is something that we all should check on our older coaches. I spent a few days bringing my AC and DC Electrical Systems back as close as I could to what should be original. I have written notes and drawn what I needed so that I can make repairs in the future.
*I am at a big disadvantage since Newell doesn't have records for my '82 so if there is someone out there with an Electrical Schematic for a '82 please copy it and I'll pay for the cost and mailing.

[encantotom]

hi steve,

i totally rewired my inverter. it was really goofy the way it was done from the previous owner. so i did it totally correct and to handle the loads better and i added in the microwave.

it was jury rigged before.

so great point on making sure things are ok that have been done over the years since it left the factory.

tom

[chockwald]

When my inverter is on every outlet in the coach works.

[prairieschooner]

Clarke, that is what we are discussing. That is not the correct way to have the Power Inverter Installed. Actually I would recommend Source Isolation with Polarity Indication if I was to Inspect that Coach during a Survey. I would bet that if you simply unplug the Shore Cord with your Power Inverter Turned On, all of the Circuits would become Hot. The Heart Power Inverter has a Relay that Automatically Switches the Power Inverter on when the Power Source is lost, these were normally sold as Computer Back Up Systems.
I would suggest that you choose what Circuits will be Powered by the Power Inverter then correct the wiring. When I was installing Power Inverters on Yachts, I would install a Separate Panel to Power only those Circuits.
Again this is why we have this Forum, I suggest that everyone check theses older Coaches and Correct them to meet Current Standards for the Safety of our loved ones, they may be the only ones to survive. Of course this may not be the case but it only takes a few minutes to prove or disprove any potential problems.

[jmacstack]

Here are todays findings: Isolated all batteries and volt tested them with my meter. They read between 13.12 to 13.15. I retested with Hydrometer and I got 2 out of 4 discs floating. These batteries are not charging 100% for some reason. Tomorrow I am going to isolate one battery and charge it with an industrial smart charger to see how it performs all by itself. If it does not take a full charge then I think I can assume these new, 1 year old hardly used batteries are toast. These batteries are WERKER brand. Anyone ever heard of them? I ordered that meter from West Marine. When it gets here I will test the output of the charger. I wish I knew more than I do as it feels frustrating to have some knowledge and not enough to fix the problem so I thank you all for your knowledge. The next big step is to have the batteries load tested...and to monitor the charger to see if it kicks on under the load test. When I installed the new charger I just cut the wires off the old charger and connected them to the new one and added an additional ground wire..probably a 10 gauge insulated wire. Could this ground wire be an a culprit here? What if the second ground wire is not actually grounded? Jennifer

[Richard and Rhonda]

Jennifer,

Why are you saying the batts are not fully charged? Are you basing that on the hydrometer or the voltage?

The chart I sent you a link to indicates to me that the batts are charged. I would go get another hydrometer of a different style and see if it reads the same as your disc one.


Steve and Tom are making excellent points for the rest of us following this thread. I have also run into some potentially dangerous coach wiring strategies when I have worked on a couple of Newells that belonged to others. It behooves all of us to verify what we have. Steve has pointed out one of the most basic principles, to verify that you do not have power when you disconnect the breakers.

Steve, do you have good reference materials for what is electrical code on RV's or boats?

[encantotom]

just my 2 cents worth, but i would not load test the batteries while still hooked up and especially with the charger on.

i would be surprised if any place would do it that way.

tom

[jmacstack]

I have charged the batteries today each individually. They are taking a charge. After being fully charged the new hydrometer I bought which is the nicest one out of the 3 that I have, read that the batteries are marginal at best and not 100%. Tomorrow the batteries are being load tested individually and not while hooked into the coach. There must be a master relay or something that is malfunctioning because I don't think the batteries are getting the signal to charge from the alternator or the charger. The merge switch is in the middle position which is where I always leave it. Tomorrow is a new day. Jennifer

[prairieschooner]

Jennifer,
I agree with Tom and Richard here, take the Coach to a shop that will do a load test on all Batteries or have them look at your Hydrometer. 13.2 Volts DC seems like the DC Batteries are Fully Charged.
Richard,
Yes, I am a Member of ABYC (American Boat and Yacht Council) and I do have a copy of the Current Recommended Standards. I use these Standards every day that I work, I use the current ABYC, USCG (United States Coast Guard) and NFPA (National Fore Protection Association) Standards in my inspections of Yachts as required by all Underwriters. These Standards are what is accepted as the Standards of the Industry. The Manual is about 2" thick and covers all of the aspects of Yachts, Engine Installations, Tankage - Fuels and Water, Heaters, Electrical, etc. If you have a question I would be glad to look it up but Source Isolation is a Basic Standard, intermingling of Power Sources can be very Dangerous. Our '82 has the Relays that perform this duty and you may remember me repairing these shortly after I bought our Prairie Schooner.

[jmacstack]

Today the batteries were load tested with a Snap-On tester not a carbon pile(sp?) All but one battery tested "Bad Battery." Tomorrow I am taking the coach to Western Sates Cat as they want to charge them and load test them with a carbon pile Load tester since that is where I bought the batteries. The batteries are less than 1 year old. All indications at this point, are leading to bad batteries. We will see what they say on Friday when I pick up the coach.

[prairieschooner]

mark one for a Hydrometer!

[folivier]

Should I drill a hole in my AGM's so I can use a hydrometer?

[prairieschooner]

good one Forest!
I have an inexpensive Load Tester that does a good job of testing Flooded Lead Acid Batteries, I think that I bought mine about 25-30 years ago. Harbor Freight sells one similar to mine, it uses a Heater Element to Simulate a Load;
http://www.harborfreight.com/100-amp-6-volt-12-volt-battery-load-tester-90636.html
still a good shop that sells Batteries has a much different way to test the Batteries.
Looks like a Tester that will properly test an AGM Battery runs between about $100 to $700. Maybe a drill isn't such a bad idea?

I had a second though for Jennifer. If your Batteries have gone bad in just one year there is a problem somewhere. Extreme Temperatures could effect the lifespan of a DC Battery but you may want to have that shop test the Charging Systems. If the Charging Voltages aren't matched to the type of Battery this could effect the Lifespan. When you have them check the Shore Power Charging System (typical Battery Charger, Charging Function of the Power Inverter) don't forget to have the Alternator checked as well.

[jmacstack]

The latest update as of Friday the 1st is this: Western States Cat removed each battery and trickle charged each one with 2 amps until charged. They load tested them and all were barely marginal to bad. They did not get consistent readings on each battery. Every repeat test gave them different information but no battery tested better than marginal. They also checked the alternator output as well as the battery charger output and all was good with both. They called Batteries Plus which is where they got the batteries from. Batteries Plus said that with that big of a battery they have to be load tested a different way. It involves a test over time under load with a specific drop in voltage over a specific period of time which takes hours on each battery. That test will happen on Tuesday. 3 tests so far, all say bad batteries. I doubt Batteries Plus will have any different results. Western States Cat has outstanding customer service and is completely standing by me and with me on this. I'll keep you all posted. I think when the batteries were new less than a year ago, they were not totally full of acid, which is why I had to put over 3 gallons of distilled water in them early spring. Everyone including me, failed to remove those covers when they were first put in my coach to check acid levels. We all assumed they were full and ready to go. With the minimal usage(only charging all winter) they were ruined. This is my theory. Jennifer

[zcasa]

Jennifer,

Your theory sounds good. I don't know much about this stuff, but I did top off my batteries every month with distilled water. I got 7 years out of them and Newell Service says that is the absolute most life that they had heard of from these kinds of batteries. They told me that they recommend replacement no longer than 3 1/2 years or so. Sounds like you will, in all likelihood, get new batteries and that you will be good to go for years to come, with routine maintenance on the water levels. Good luck tomorrow. It will feel good to get to the bottom of this challenge.

David

[jmacstack]

Here are the final results to the Batteries that wouldn't take a full charge. Batteries Plus says they're fine. End of Story.

[prairieschooner]

something sounds wrong here.
Your earlier post states that the supplier of the batteries could not get a good reading and you could not get a good reading. Have you tried to get a reading since the batteries were returned? or could you get the supplier to test them again and make sure that everyone puts something in writing.
If the batteries are fine then something should have been wrong with the charging system. If there is nothing wrong with the charging system then...
I suggest that you have another source evaluate the batteries and charging system as a second opinion, this shouldn't take too long and should really help to explain this.
but hey this is me and I don't like throwing $$$$ away.
Good Luck.

[jmacstack]

I agree Steve. I tested them, Western States Cat tested them and they all tested marginal to bad. Batteries Plus tested them which is where Western States got them, and they say they are fine. They load test them with a 60 watt bulb until discharged, then recharge them at 2 volts. These are really big batteries and apparently that is how to load test these as well as charge them. I'm wondering if these batteries are the right sort of batteries to have in my coach. They are a match to what I replaced them with. The charging system all checks out good. Western States rechecked them and left the coach lights on as well as the fridge and ice maker for 8 hours. The gauge on the panel was reading 12.3 at the end of the 8 hours and the reading a the batteries read, 12.6. Perhaps it is a gauge accuracy issue. I'm using the coach this weekend and I will check it out again.

[prairieschooner]

good luck I am sure that you are a bit frustrated.

[Richard and Rhonda]

Jen,

What kind of batteries are they? Standard wet cell cranking batteries, wet cell deep cycle batteries, gel batteries, marine batteries, or AGM deep cycle batteries?

Since this is such a long thread, can you remind us old geezers, what data you have that says they are bad? Hydrometer, short life, voltage on batteries, charger never turns off?

Steve,

I thought you would take some delight in my hydrometer use yesterday. I lost one of the batteries in my house bank. And yes I did use a 4 buck hydrometer to confirm it had two bad cells.

[prairieschooner]

just a little Richard.
Jennifer said that she had used a hydrometer and referred to the lead plates being exposed earlier in this post so it leads me to believe that she has Flooded Lead Acid DC Batteries.
If the plates were exposed after a long period of charging they could have been sent through a conditioning charge to help remove any sulfate on the plates to help restore the batteries. I know that Lifeline recommends this for their AGM batteries on a yearly basis. My Heart Power Inverter has this function so I would expect most of the newer chargers to have it as well.
All we can do is speculate although I would recommend that she finds the answer before replacing the batteries.

[encantotom]

i gotta respectfully disagree with batteries plus.

there is a reason those big 8D's are rated at such high cold cranking amps. that is to turn over our big starters.

putting a light bulb on it to load test it is nuts. an 8D with several bad cells will still test ok with a 50 amp load let alone with a 60 watt light bulb which is 5 amps at 12 volts.

if you research it, you will find that you have to test an 8D with a load that is close to equivalent to the load put on it by starting it. that means 600-800 amps. there are carbon pile load testers that will test that.

i bought my starter batteries at sams club and they could test them and my agm batteries for my coach side at interestate batteries and they could test them.

just my two cents worth. and you get what you pay for.

btw, there is a reason there are 2-0 or 4-0 battery cables on our rigs. current draw.....

tom

[jmacstack]

Tom, these batteries are not 8D's. They are way bigger than that. These batteries are at least 20 inches high and 12-14 inches long. I think I described their specs at the beginning of this thread. And, I agree with you. Jennifer

[encantotom]

the 8D batteries that most of us have i believe are the biggest batteries that you can get. they weigh about 170 pounds are are huge.

no matter what batteries you have, they are meant to take a severe current load so i think my comments are still valid on the load testing.
tom

[jmacstack]

Tom, I have 8D's for my starters and these are a lot bigger in size, as in taller. Whatever they are, I agree with you. I tested them today with my hydrometer and they tested in the white and not in the green where they should. I will test them again after being plugged in for 3 days.