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SWharton

Still having b attery problems

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Super thread, of fellow Escapees all sharing their knowledge. 

I like the basics of first making sure everything is properly installed wiring wise. The understanding 'baseline' tests of current battery capacity and battery health that Al's testing. 

I may have missed it in the posts of this thread, but I'd also double check the charger program settings, to ensure that the charge parameters are properly set for the specific brand of AGM in the rig. (A simple statement here is that Lifeline's use a slightly different charge settings then almost all other AGM's.) 

One other tip on trying to reduce parasitic draw. Read and ask questions on your specific rig on an owner's forum. As many rigs have 'uniqueness' in wiring and system's, and the 'collective' of other owner's will probably have others that have chased down these parasitic draws before:)!

Best to you, and all,

Smitty

 

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19 hours ago, Smitty77_7 said:

Super thread, of fellow Escapees all sharing their knowledge. .........................

One other tip on trying to reduce parasitic draw. Read and ask questions on your specific rig on an owner's forum. As many rigs have 'uniqueness' in wiring and system's, and the 'collective' of other owner's will probably have others that have chased down these parasitic draws before:)!

Best to you, and all,

Smitty

 

Hopefully the parasitic draw would be fairly easy to track down, since the OP has a battery monitor which should show the number of amps being pulled out of the batteries.  Assuming only one cable goes to the single negative post on the battery bank that feeds the the shunt and RV.  If there is a load over about 1 amp, start pulling fuses.  If you have pulled all the 12V fuses and disconnected the inverter negative cable, and you still have a load on the battery.  That gets to be difficult and time to do what you suggest, ask that specific question:  "All fuses pulled, but load is still there.  Now what?"

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We have done all our battery measurements and put them in a spread sheet. If you have any questions regarding the numbers(or interpreting the numbers) please let me know. Measuring by amp hours things look better than looking at the volts.

Thanks for any help/assurances you can provide.

No rush since we are in winter camp..............

battery.info.xls

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How are you measuring the AH used and SOC?  Do you have a battery monitor installed for this?

Is the AH used a cumulative number going down the column?  If so, the positive numbers are charging AH and the negative are discharging correct?

Looking at line 13 (micro wave for 6 minutes) you say it used -21 AH.  A 1500 watt microwave should only use about 10 AH in five minutes, thus, the 21 AH seems on the high side making me question how your measuring things.  Plus, the SOC dropped 3% which is a little over 12AH out of your 420 AH bank - more in line with what I would expect from your microwave.  Ya see where I am confused?

Where are you parked at for the winter?  Wish I could swing by and help.

Lenp

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We are heading out the door, will reply tomorrow. We are in north Phoenix for the winter. and yes we have a Magnum monitor.

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We have a Magnum inverter with remote panel ME-RC and a sense module ME-BMK.  That is where we are getting all the numbers.  AH is an instantaneous number (more or less).  Plus is charging and negative is discharging.

rAH is a cumulative since last reset.  It was reset to zero before the testing.

Line 13 with micro wave running for 6 minutes.  After micro wave started, the refrigerator started and ran for a few minutes.  That is probably why the numbers look a little high.

There is still a ground wire from the battery bank to the frame.  When disconnected for a test, several items in the motor home went off so I reconnected it.  I will be looking at the circuit panels to see where ground lines go.  If to frame, I will reroute the to sense module.

We think we are OK, just trying to make sure and understand what we have.

Thanks

 

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Line 13 makes a little more sense now.  Thanks.

To properly measure the charge and discharge of your batteries ALL of the circuits should pass through the "sense" module.  My Pantametric unit has a 0.001 ohm shunt that is wired between the negative terminals of the batteries and ground.  All loads and charging equipment connect directly to ground so everything is passing through the shunt.   If someone rewired your negative side and bypassed the "sense" module (shunt??) all of your charge and discharge measurement are going to be inaccurate.

If your numbers are accurate I don't see a real problem.  As I noted earlier, mine will drop down to around 70% if I run both the frig and the freezer.  Frig alone it drops to around 80% just like your seeing.

Lenp

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Your readings look pretty normal.  As you said, using AH instead of volts, things look better. 

You need to move the cable that goes to frame ground to the Shunt (sense module), otherwise you will not be measuring all the AH going out of the batteries.  It really doesn't matter very much what is being powered by the cable going to frame ground, other than it is nice to know.  What is important is that the monitor measures everything going out and in the batteries. 

The very good news is, that when you connected to shore power at 7:45am your inverter/charger took you from around 70-72% to 92% in an hour. Then at the 2 hour mark you were close to 100%.  The generator would have done the same.  Another thing of note, is that even after the monitor showing 99% at 9:35 the charger sill put in another 16AH over the next 2 hours.  That is normal operation in my experience. 

At the 8:44 time, where you were at 92%,  this is were 400-600 watts of solar would come into play.  Switching off your generator at 90-92%, then the solar would have brought you to 100% on a bright sunny day.  Even a partly cloudy, or light clouds solar should support your fridge and other usage during the day. 

Not having solar, would mean you really are going to need to run your generator for another 2 or more hours in the late afternoon or evening to get your batteries back up to the 90-93% level to support your needs though the night.  Also in the morning you will need 2-3 hours of generator time. 

A word of caution about dry camping or boondocking.  With your up coming trip to Alaska next year you could easily go for a week or three without hooking to shore power.  For good sustainable battery life you want to get your batteries to 100% every 4-7 days.   If you go for 2-3 weeks w/o getting to 100% you reduce your battery life somewhat, but not hugely.  Repeatedly not getting to 100% except for once every 2-3 weeks, over a 4 month period, will have some amount of negative impact on your battery life.  How much?  I have not see any figures.  With so many variables it would be hard to measure.  If you only went down to 75% SOC and back up to 92% that is one thing.  Going down to 50-60% SOC and back to 92% would have more impact.    Reduced battery life means that over a the 4 month period, I mentioned above, your total battery capacity may be reduced from 400AH to some lower number.  Maybe 375AH or even 350AH capacity. 

Also keep in mind if you only get to 92% and then that night you use another 100AH, as you did in your test, your batteries will have dropped lower than the 70-72% you had in the morning in your test.  Now you have to run your generator longer, or the next night you are even lower in the morning. 

When you do start to use your batteries for dry camping, plan on running an "equalize cycle" on your charger about once a month.  This helps reduce the sulfating of your battery plates.  Consistently not getting to 100% causes sulfating which reduces battery capacity.

More info about equalizing AGM batteries here:  http://lifelinebatteries.com/2015/10/can-i-equalize-agm-batteries/

Bottom line, you are on the right track to knowing your usage and charging needs.  As my mother used to say, knowing is half the battle.  :D

 

Edited by Al F

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We are thinking of adding another solar panel to help things along before Alaska. We had read someplace about needing to get to 100% charge at least once a week and will be doing a commercial cg at least once a week(we are not dedicated boondockers) for laundry, rest day etc. We just want the flexibility of boondocking when we want.

Plans to rewire are on the list.

Looking at the amps has calmed us down. Historically, everything talks volts so naturally that is what we looked at.

With all your patience and guidance we are more comfortable with what we have and how we use it.

Al, you mother was very wise. Knowledge is power.

I hope this thread benefits someone else in the future.

 

 

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On your trip to Alaska you should be charging the batteries every day your driving and you will probably be getting them close to 100% after a few hours of travel.

Another thing to keep in mind is to try not to let them get below the 50% level.  I read an article several years ago claiming battery life would be greatly enhanced by keeping them above that level.  Article stated a batter taken from the 90% to the 10% SOC would last roughly 200 cycles.  Keeping them between 90% and 50% will result in a 2000 cycle live - ten times longer.  Fact or fiction?  I can tell you the last set of six Trojan T105 batteries (in my last rig) lasted over eight years and were still going strong when I replaced them.  Only reason I replaced them is I made a mistake when topping them off and grabbed the white vinegar instead of distilled water.

Lenp

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Thanks Len, we must have read the same article.

With everyone's help we are now comfortable with what we have and know better how to manage it. Plan to rewire in the next few weeks but need to tackle a hydraulic problem first.

RVs are just like houses, something every day to fix.

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If I remove the cable from battery negative terminal that currently goes to the frame, do I change the connection to battery negative to shunt load side or a cable from shunt load side to frame?

 

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All the negative battery leads should be tied together and then connected at the BATTERY side of the shunt.  You could wire all battery negatives together and then one cable to the shunt or all three batteries negative terminals could be connected to one side of the shunt and then ONE lead goes from other side of the shunt to the chassis.  All current must travel through the shunt.  Here is a diagram of mine:

Lenp

 

BatteryWiring.jpg

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17 hours ago, SWharton said:

If I remove the cable from battery negative terminal that currently goes to the frame, do I change the connection to battery negative to shunt load side or a cable from shunt load side to frame?

 

The cable needs to go to the house side of the shunt so whatever current is coming from the frame of the RV goes through the shunt and then to the battery. 

 

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I am reporting back. We have moved the wire and now are seeing a higher amp hour than previously. To me this represents a more realistic usage. We won't do any further testing at this point but feel we have a handle on the battery situation,

Thanks to all for all your help.

 

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I am reporting back. We have moved the wire and now are seeing a higher amp hour usage than previously. To me this represents a more realistic usage. We won't do any further testing at this point but feel we have a handle on the battery situation,

Thanks to all for all your help.

 

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Next step could be to start pulling 12V fuses and unplugging 120V AC devices while watching the battery monitor on the amps setting to see what is using power.  Hopefully you will find things you can unplug or disconnect when not needed to reduce your usage.

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We have a problem with doing this. Most of the circuits have circuit breakers, push to reset, no way to break the connection. Very few fuses. We will look into it more in January, life is beginning to get hectic.

Thanks

 

Edited by SWharton

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On 11/8/2017 at 4:30 AM, Al F said:

Your readings look pretty normal.  As you said, using AH instead of volts, things look better. 

You need to move the cable that goes to frame ground to the Shunt (sense module), otherwise you will not be measuring all the AH going out of the batteries.  It really doesn't matter very much what is being powered by the cable going to frame ground, other than it is nice to know.  What is important is that the monitor measures everything going out and in the batteries. 

The very good news is, that when you connected to shore power at 7:45am your inverter/charger took you from around 70-72% to 92% in an hour. Then at the 2 hour mark you were close to 100%.  The generator would have done the same.  Another thing of note, is that even after the monitor showing 99% at 9:35 the charger sill put in another 16AH over the next 2 hours.  That is normal operation in my experience. 

At the 8:44 time, where you were at 92%,  this is were 400-600 watts of solar would come into play.  Switching off your generator at 90-92%, then the solar would have brought you to 100% on a bright sunny day.  Even a partly cloudy, or light clouds solar should support your fridge and other usage during the day. 

Not having solar, would mean you really are going to need to run your generator for another 2 or more hours in the late afternoon or evening to get your batteries back up to the 90-93% level to support your needs though the night.  Also in the morning you will need 2-3 hours of generator time. 

A word of caution about dry camping or boondocking.  With your up coming trip to Alaska next year you could easily go for a week or three without hooking to shore power.  For good sustainable battery life you want to get your batteries to 100% every 4-7 days.   If you go for 2-3 weeks w/o getting to 100% you reduce your battery life somewhat, but not hugely.  Repeatedly not getting to 100% except for once every 2-3 weeks, over a 4 month period, will have some amount of negative impact on your battery life.  How much?  I have not see any figures.  With so many variables it would be hard to measure.  If you only went down to 75% SOC and back up to 92% that is one thing.  Going down to 50-60% SOC and back to 92% would have more impact.    Reduced battery life means that over a the 4 month period, I mentioned above, your total battery capacity may be reduced from 400AH to some lower number.  Maybe 375AH or even 350AH capacity. 

Also keep in mind if you only get to 92% and then that night you use another 100AH, as you did in your test, your batteries will have dropped lower than the 70-72% you had in the morning in your test.  Now you have to run your generator longer, or the next night you are even lower in the morning. 

When you do start to use your batteries for dry camping, plan on running an "equalize cycle" on your charger about once a month.  This helps reduce the sulfating of your battery plates.  Consistently not getting to 100% causes sulfating which reduces battery capacity.

More info about equalizing AGM batteries here:  http://lifelinebatteries.com/2015/10/can-i-equalize-agm-batteries/

Bottom line, you are on the right track to knowing your usage and charging needs.  As my mother used to say, knowing is half the battle.  :D

 

Al,

FYI. We have been researching equalizing and our batteries should not be equalized. This seems to be unique to Lifeline AGM batteries. We are Duracell(Deka or East Penn) and Magnum does not allow them to be equalized, only the Lifeline. There is an option to select what battery you have on the Magnum control panel, AGM-1 is for Lifeline, AGM-2 is everyone else.

We are very happy with our system right now and will get another panel, brings us up to 370 watts. Can't quite rationalize a third panel at this point.

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18 hours ago, SWharton said:

Al,

FYI. We have been researching equalizing and our batteries should not be equalized. This seems to be unique to Lifeline AGM batteries. We are Duracell(Deka or East Penn) and Magnum does not allow them to be equalized, only the Lifeline. There is an option to select what battery you have on the Magnum control panel, AGM-1 is for Lifeline, AGM-2 is everyone else.

We are very happy with our system right now and will get another panel, brings us up to 370 watts. Can't quite rationalize a third panel at this point.

Congratulations. You have come a long way from your original concerns and problems of several months ago.  With your additional solar panel and good monitoring of your battery amp hour usage you should have good experiences with dry camping and/or boondocking.  

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Thank you very much. I am sure in our being educated we have taught others who followed along.

Love the support of Escapees...............

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I've been watching this thread but it seemed like everything was getting sorted just fine so I kept my mouth shut.

Just to clarify some myths and misconceptions, though. Not specifically from this thread, but in general information you might have run across as you were doing your homework.

1. Not everything you read on the internet is accurate. ;) In relation to batteries and chargers, much of what you might read is often outdated and or just folks "regurgitating" what "someone" read "somewhere" or spoke directly with a C.S. rep who told them "such and such" where the C.S. folks have no practical experience outside of what they've been forced to memorize from their companies own sales cheat sheets. That might also be outdated or "published information" that is many times edited for considerations outside of a particular companies actual battery performance specifications.

If you look.. you will often find that actual owners manuals and company tech sheets will contradict what their own brochures or other information that is routinely disseminated to the masses says. Between battery mfg. and controller/charger companies? Well... they aren't exactly held to any standard of what to disseminate to whom under what kind of time frame... or even that those companies have any obligation to update their algorithms in a timely fashion.

Getting specific. Magnums "AGM 1" and "AGM 2" profiles. Magnum is attempting to follow the charging profiles outlined by the manufacturers. The numbers they are given are OFTEN a culmination and compromise between lifespan, taking in to account user error and safety standards that come down from "somewhere or other" within their respective companies. The charge profiles are RARELY geared between a balanced lifecycle and performance standpoint in any given application. You also need to take into account that lifeline AGM's are not solely used by the RV world and rarely fed by a solar controller. Lifeline does not provide "suggested charge profiles" based on application.

So AGM 1. Magnum is saying that lifeline has told them that the optimal absorption charge is 14.3vdc. If you go to the lifeline website or call their C.S. department they say their AGM's optimal charge rate is 14.4-14.5vdc, and completely seperate from that, their tech manuals state 14.6-14.8vdc w/temp compensation.

Float charges? Magnum AGM 1 is set for 13.1vdc. Lifeline says 13.4-13.5vdc. Equalization? Magnum AGM 1 is set for 15.5vdc. Lifeline says 15.6-15.7vdc.

Of course... those are all "blanket" setting with also no regard to 12v AGM vs. 6v batteries.. which are able to accept higher voltage as well as a specific ambient temperature of 60-70 degrees.

Equalization. Lifeline (concord) is one of the very few AGM battery companies that has come "out of the closet" about equalizing an AGM. The truth of the matter is that AGM's are wet cell batteries and are subject to many of the same conditions that can shorten the life of a standard wet cell. IOW.. AGM's "CAN" be equalized. However... lifeline has gone "way" overboard by recommending regular equalization, but that's just my own opinion. It stresses "any" type of battery (AGM's even moreso) and should be used as needed.. not as a matter of course.

Why? I dunno. Maybe it's a "look at us.. we're different.. we can do what no other AGM mfg can" deal. 

No other companies are openly encouraging equalization so that means magnum is going to create an AGM 2 charge profile. What's especially funny about that is that their AGM 2 profile (for every other AGM) is a VAST improvement over the rather anemic AGM 1 (14.3/13.1) set aside solely for lifeline AGM's. AGM 2 is 14.5v/13.5v.

So, let's make this "practical". If you're running solar... and your array and charger is properly sized for your battery bank... it would seem to make sense that you would try to maximize the amount of energy production going back in to your battery bank within the limited amount of time of actual solar production.. would it not?

Don't get me wrong. There is "nothing" wrong with Magnum's gear. I run one myself. Their profiles are.. let's say... conservative (aka reflecting industry confusion).. but that's why they invented the "custom" option. ;)

To each their own in how everyone chooses to run their battery banks, but in my house my magnum and controller use custom settings and I run mine (lifeline 6v AGM's) temp compensated at 14.7/13.6 and only run manual equalization cycles as needed. One consideration also needs to be what ambient temps you generally camp in. I "goldilocks" and have temp comp so I can "push" my bank a little harder. Even without it though I would be running my lifelines at 14.6/13.5. With almost 5 years on my current bank.. I've run an equalization 3 times.

Probably needless to mention this but there may "also" be a variation (due to current bleed) of what you set your controller/charger to output and what is actually hitting your battery bank posts. Adjust output accordingly. That's the main issue I have with stock converters and wiring. The monitor says 14.4v, but you may actually only be getting 13.8v at your battery.

All that said... I rely on solar as my primary energy source. Maximizing output is paramount. If you mainly rely on your battery bank to get you from point A to B and then on shore power the majority of the time, it's not necessary to "push" your battery banks. There are a number of other considerations to factor in... loads, duration, etc. that may have more impact on your battery banks health than someone else's.

I'm not saying, "DO THIS". I am saying to do your research and make an effective power management plan specific to your needs and lifestyle.

There! I think my rant box is empty now. :lol: 

For the curious.. the Concord tech specs I used in the above is Doc. #: 6-0101 Rev.: E from 02/02/17 

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