I may have killed RV deep cycle sealed chassis batteries installed by dealer?

[Bruce S]

Distilled water is readily available.  Anyone who has a dehumidifier in their home is collecting distilled water.  I use this water exclusively since I no longer have ready access to a demineralized/deionized supply.  Never had a problem and my batteries last and last...

[Grey Goose]

On 3/1/2023 at 7:47 PM, Tom Cherry said:

Couple of quick points.

Starting batteries will NOT last as House.  You need Deep Cycle Marine & RV types.

Lithium batteries for the novice may be a financial disaster. Many here believe that the Magnum Inverter is NOT suited for charging or maintaining and there are countless debates. MOST experienced folks that absolutely have to have Lithium and also some solar end up upgrading their charger with a supplemental and a new controller.

Your Magnum Controller is NOT suitable for Lithiums.  The newer ME-RC remote has more options but folks feel it is still inadequate

Flooded cells are STILL the choice (mine) for many experienced users here. AGM required a knowledgeable setup and monitoring and any missteps or abuse will shorten their life as well.  YES, we are the old timey Buggy Whip Guys.  BUT, I know some, like me that are getting up to 8 years of more out of our Trojan T105's.  We MAINTAIN them and EXERCISE them.  We us a relatively inexpensive Battery Miser Cap (Amazon) so the electrolyte does NOT boil off, but condenses and drops back in.  We rarely add an ounce of DISTILLED water every six months or so.  Our batteries after 7 or so years will STILL charge back up to almost 100%.

I have included a Battery "Guide" that I put togehter. Many have read and like it.  It is a few pages long.  BUT, it explains what you need to know and also how to choose batteries and how to get the best life out of them.

If you plan to update (maybe you have) to a Res Refer, your FOUR bank set will do nicely.  Folks that are experienced all conclude that with the addition or replacement of the incandescent lights (we have INFO here) with LED's and also knowing that you need to TURN OFF (unplug or have a power strip) your TV's and such when you boondock, you easily get a full 24 hour cycle and you only run your generator for maybe 2 - 3 hours per day.

That's it.  Learn about Batteries.  Read before you buy.  Sometimes folks have GREAT results from Sams and Costco. Locally, I could buy Interstates cheaper at the Distributor than at Costco.  I use Interstate STARTING batteries.  

BUT, I only use Trojan T-105's for the house....and they last...and IF you happen to abuse them, they are forgiving.  AGM's a little.  LITHIUM....NOPE.  Kid gloves.  BUT if you understand that and take care of them and upgrade the system....they are the nuts.  BUT, not for me....

I uploaded my original copy...but this is the one that is in the files...

 

BATTERY 101 - BECOME AN EXPERT.pdf 320.41 kB · 19 downloads

Any idea why folks feel like the ME-RC is inadaquate for Lithium house batteries?

[Tom Cherry]

2 hours ago, Grey Goose said:

Any idea why folks feel like the ME-RC is inadaquate for Lithium house batteries?

The “advanced” ME is,, or highly recommend for Magnum’s Battery Monitoring Kit.  The BMK is an advanced (complex for some….simple for others) that lets the owner thoroughly monitor and control the charging function.  With the ME-ACR. (NAME ?), YOU have the ultimate in control and instrumentation to let you know the exact SOC.  IT does lack a feature wher you could install Specific Gravity sensors so that you have instantaneous reading on your bank.  This is not my cup of tea.  But others that are very learned and electronically inclined feel they can prolong like and that the batteries are being charged properly.

if I had AGM’s, I would want it. Many use it on larger (8 total) banks as charging issues can be double the cost of a standard bank.

Lithium would be a “must” in my opinion.  If I had an older or original inverter, I would want to know what features the new model has that my 15 year old inverter does not have and which of those might be recommended or required for Lithium.

Many here, that are very technically inclined, have opted to keep their old inverter for inverting, but put in a stand alone system for charging as they feel that Magnum is not sufficiently technologically advanced for properly charging (improper charging will destroy the Lithium cells) them.  Put LITHIUM in the search box and use TOPICS.  MANY hits with many examples of “opps….there went a big $$ upgrade” or, “having researched this, I decided to charge in this manner”.  Lots of great exchanges and quite informative.

simply put.  Going from Flooded to AGM is costly and one’s knowledge needs to be at a much higher technological level.  This is not a panacea to fix problems, but an opportunity to damage a more costly bank.  If one thinks just popping in a set of AGM will eliminate future battery issues and they will last forever and no preventative maintenance nor understanding of the differences….then one will be disappointed.

Same goes for Lithium.  Except maybe 5 times more the Med for understanding.  We are fortunate to have very knowledgeable members.

AGM and Lithium have many advantages, but a simple error or setup or a glitch in the charging system can damage them.  Likewise Lithium is even more frag8le.

But properly installed and knowledgeably understood and monitored (BMK), They perform well.

The question come up….do I need an ME-ACR is asked.  The advice is stick with the ME-RC UNLESS you feel the need for state of the art measurement….or an insurance policy on a high quality ($$) bank of AGM’s.  Read the following for a better understanding…..

 

 

 

 

 

[cbr046]

To monitor SOC I installed a pair of these -

https://www.amazon.com/gp/product/B07V8S9PCX/

They'll monitor FLA / AGM or Lithium (programmable) and percentage or volts.  I like percentage as it minimizes thinking, and I can glance at them while driving or stepping in/out of the coach.  They stay on all the time . . . . and remind me I need to shut off the chassis battery! 

I nibbled out an aluminum sheet for a holder then connected them to the coach battery test switch.  For $12 each it was a GREAT investment. 

- bob

 

- bob

 

 

[Tom Cherry]

28 minutes ago, cbr046 said:

To monitor SOC I installed a pair of these -

https://www.amazon.com/gp/product/B07V8S9PCX/

They'll monitor FLA / AGM or Lithium (programmable) and percentage or volts.  I like percentage as it minimizes thinking, and I can glance at them while driving or stepping in/out of the coach.  They stay on all the time . . . . and remind me I need to shut off the chassis battery! 

I nibbled out an aluminum sheet for a holder then connected them to the coach battery test switch.  For $12 each it was a GREAT investment. 

- bob

 

- bob

 

 

Interesting.  At least you got past the “instructions”.  A verification draw down test would confirm their accuracy as well as functionality.  Draw down the house to 50% SOC.  Since this is a voltage measurement, 50% should read when the voltage at 5he battery reads around 12.0 or bounces between 11.9/12.0.  You can do this on the fly. Remember that the load voltage will be lower than the real, recovery voltage. Typically 0.0t-0.15 VDC….

OK.  NOW complete the recommended exercise of your batteries, assuming FLA.  I always measure SG & VOLTAGE.  If you don’t have a SG meter, then use your VOM.  Now measure your voltage after removing surface charge and a 5 minute rest with the jumpers removed.  That is the true SOC.  See or record the voltage immediately after you reinstall the jumpers.  
Use the Trojan tables.  Interpolate as needed.  If the SOC from the chart matches the % on the house meter, right after you reconnect the jumpers, then it is measuring SOC.

Let know.  Thanks.

[cbr046]

To be honest @Tom Cherry their accuracy isn't important to me.  Please don't flip out but with these batts I'm not concerned with exacting details.  I'm more interested in relative SOC, not absolute.  It's a good 'nuff system. 

My batteries are in poor condition and should be replaced.  When we bought the coach 2 yrs ago the electrolyte was so low the plates were exposed, and no telling how long or how much of the plate surfaces were exposed.  The FLA's have slight swelling, another tell-tale sign they're short timers.  The chassis AGM's don't hold a charge for long.  The photo above the AGM's dropped 20% in 48 hrs (ECM draw?).  But I'll keep using both sets until I get the last coulomb out of them.  I can run a few lights, and watch TV all night without going below 50% and recharge the next day, which is usually a travel day (engine generator recharges coach batts).  I can't run the microwave and in theory I should (1200W uwave on a 2000W inverter) but for $500 for Sam's Club / Costco Duracells vs starting the generator . . . . I'll start the generator! 

I have a set of "floating balls" SG tester.  It's pretty flaky.  I do like the idea of something with a real SG reading.  👍

If you want a real laugh my in-dash voltmeter drops from 13-14 to 9-10 if I turn on the headlights!  It's all in the poor connections (or grounds) under the dash.  Getting in there is near impossible.  Laying on my back and getting 2 hands / arms in there without being a contortionist *IS* impossible!  Hence the real drive for the aux voltmeters. 

Does it sound like I'm ranting?? 

No worries.  Someday I'll buy new batts, install a water recovery system and get detailed about my new investment.  Heck, I may even spring for Trojan T105's!  But until then . . . . .

Best,

- bob

[Tom Cherry]

2 hours ago, cbr046 said:

To be honest @Tom Cherry their accuracy isn't important to me.  Please don't flip out but with these batts I'm not concerned with exacting details.  I'm more interested in relative SOC, not absolute.  It's a good 'nuff system. 

My batteries are in poor condition and should be replaced.  When we bought the coach 2 yrs ago the electrolyte was so low the plates were exposed, and no telling how long or how much of the plate surfaces were exposed.  The FLA's have slight swelling, another tell-tale sign they're short timers.  The chassis AGM's don't hold a charge for long.  The photo above the AGM's dropped 20% in 48 hrs (ECM draw?).  But I'll keep using both sets until I get the last coulomb out of them.  I can run a few lights, and watch TV all night without going below 50% and recharge the next day, which is usually a travel day (engine generator recharges coach batts).  I can't run the microwave and in theory I should (1200W uwave on a 2000W inverter) but for $500 for Sam's Club / Costco Duracells vs starting the generator . . . . I'll start the generator! 

I have a set of "floating balls" SG tester.  It's pretty flaky.  I do like the idea of something with a real SG reading.  👍

If you want a real laugh my in-dash voltmeter drops from 13-14 to 9-10 if I turn on the headlights!  It's all in the poor connections (or grounds) under the dash.  Getting in there is near impossible.  Laying on my back and getting 2 hands / arms in there without being a contortionist *IS* impossible!  Hence the real drive for the aux voltmeters. 

Does it sound like I'm ranting?? 

No worries.  Someday I'll buy new batts, install a water recovery system and get detailed about my new investment.  Heck, I may even spring for Trojan T105's!  But until then . . . . .

Best,

- bob

sounds like you have the basics.  as to the "SOC METERS", I wouldn't call them that.  They are just an adjustable VOM that you set the scale for the "advertised" voltage of what you want to measure.  So you choose 12 vdc.  IT READS IN VDC or PERCENT. Technically, if your inverter is workin and your float charge is 13.5%, the meter should read 113%. You've let the cat out of the bag, these will not replace the Magnum $450 or so BATTERY MONITORING KIT....  LOL

As long as you understand what they measure....use them. Most folks opt for Trojan T105 and usually Interstate starting.  both Lead Acid.

[96 EVO]

I'm looking into replacing my house bank with Roll's 6v FLA batteries.

About 40% BETTER, than Trojan's.

[Tom Cherry]

2 hours ago, 96 EVO said:

I'm looking into replacing my house bank with Roll's 6v FLA batteries.

About 40% BETTER, than Trojan's.

Nice looking batteries.  Trojan also makes the higher capacity “Two Men & a Boy” 16” battery.(100 pounds).  The heavier Trojans were never a bargain.  Last time I did the math, you spent at least 30% more per AMP HOUR.  BUT, you do have more Amp Hours in your stable.  

Four (4) of the Rolls will be, without tax, $2,000.  Monaco pulled out the trays when they went to the higher Trojans as the rollers would not support them.  It as a “add on” if you got a Res Refer in the Camelot/scepter.  You also got a supplemental or separate standalone 1,000 watt inverter for the Res refer.

OK….  THE MATH.  428 AH X 2 = 856 AH   Or $2.34 per AH.

REGULAR TROJANS.  225 Ah X 2 = 450 AH.   Set of 4 is around $750 or cheaper.  That is $1.67 per AH.  The Rolls is 40% MORE per AH.  A PRICEY UPGRADE.  That is not surprising as the taller Trojans were at least 30%….usually higher as most Golf Cart shops didn’t stock so you paid extra shipping.  

The Standard Magnum puts out 100 A DC.  MAGNUM tells folks that the older the units might need to back off on charging.  Some still run 2008/09 @ 100§….I don’t. I stay at 80 and drop back to 70 during high temps as the FET’s get hot and you get warning lights. Now some Dynasty and upper ends have 8 batteries so a complete 50% drawdown will take twice as long.  I guess I’m frugal and paranoid….  My T105 works for my needs and I can swap them out.  The larger ones are a back breaker to pull and you scar and scuff up the floor making it more prone to corrosion and more maintenance. Here is an equivalent Trojan, the same series Monaco used.  If I Eyeballed the math, the Rolls and the Trojan would be the same.  411 AH for $442.  Most here would opt for the Trojan….based on life and experience and history.

https://www.bigtimebattery.com/store/trojan-l16e-AC-replacement-battery.html

Something to consider…..when you are spending 2.5X the cost of an ordinary premium bank of Trojans.  Several Camelot owners put in trays and went back to the OEM design due to ease of service.

interesting…..thanks.

[96 EVO]

Well, I may not be desperate for a new house bank after all!

Gave my 7yr old Interstate GC2 bank a 2.5hr equalize charge, followed with a couple of cycles down to 12.0v using my coffee maker, which put's a 90A drain on the batteries for about 10-12min a shot.

After these two cycles, I was able to brew 5 pot's of coffee back to back (short cool down for the inverter between brews), to get the bank down to 12.1v resting.

Not too bad!

I guess just keeping your FLA batteries on 13.4-14v float charge for many weeks, doesn't mean they are ready to go to work!

Edited March 13, 2023 by 96 EVO

[Tom Cherry]

3 hours ago, 96 EVO said:

Well, I may not be desperate for a new house bank after all!

Gave my 7yr old Interstate GC2 bank a 2.5hr equalize charge, followed with a couple of cycles down to 12.0v using my coffee maker, which put's a 90A drain on the batteries for about 10-12min a shot.

After these two cycles, I was able to brew 5 pot's of coffee back to back (short cool down for the inverter between brews), to get the bank down to 12.1v resting.

Not too bad!

I guess just keeping your FLA batteries on 13.4-14v float charge for many weeks, doesn't mean they are ready to go to work!

Correct.  FWIW, Trojan advises against equalizing.  If you want to know why, exactly, call their tech support.  Magnum discusses it.  However, my gut feeling is that equalization should only be done over strict controlled conditions.  But, if you are inclined to do it, then stringent controls should be used.  For inverters that are 10 + years old, I would set the charge rate to 50/60% and add supplemental cooling like leaving both doors of the bay open and a fan blowing.  

As to exercising, the recommended practice is to pull down the batteries to 50% SOC, which equates to an actual load voltage of 11.8/9.  Then let them rest. Check the electrolyte and recharge.  If you don’t want to know what the real condition of the battery is, do the cycle 3 times…use about a 25/30 A (DC) load.  Then whatever you get, you get.  Taking them down partially to say 60% to be safe is false economy as they only have so many cycles.  Deep cycling to a load voltage of 11.8/9…READ directly at the batteries under load is perfect.

Glad you have some life in your bank.  You and you camping needs and your pocketbook and maybe back can make the call once they will not charge back up to but 12.0 VDC, AFTER you knock off the surface charge and let them sit a few minutes with the jumpers removed. Then they are gone, or you know they are half depleted and can’t deliver full voltage.

[96 EVO]

What do you use to put a 20-30A DC load on your batteries?

I was thinking 'maybe' a large box fan I have in the house may do it, but just went with the coffee maker which was already in the coach. As I said, it draws 90A.

BTW, it's amazing how quick an equalize charge will get a bank of FLA batteries boiling! I watched the amps go up on my display, by the time I got to the battery tray, they were already bubbling!

Edited March 14, 2023 by 96 EVO

[Tom Cherry]

30 A DC X 12 = 360 Watts.  Watts is Watts.  There are a variety of quartz halogen work lights out there.  I have used a 250 & have a 450.  The recommended “load” would be 300 Watts for a bank of 4.  Obviously double that for a bank of 8.  A lower wattage will work, but takes longer.  Don’t oversize it as the drawdown is not good..  Look at small hair dryers…. If you still have old incandescent bulbs, hook up an array.  4 of the 75 watt spotlight/floodlights would work fine.

 

[cbr046]

On 3/13/2023 at 8:54 PM, Tom Cherry said:

30 A DC X 12 = 360 Watts.  Watts is Watts.  There are a variety of quartz halogen work lights out there.  I have used a 250 & have a 450.  . . . .  Look at small hair dryers…. If you still have old incandescent bulbs, hook up an array.  4 of the 75 watt spotlight/floodlights would work fine.

Or the infamous wet bay heater!

- b

[96 EVO]

1 hour ago, cbr046 said:

Or the infamous wet bay heater!

- b

Pulled the 12v Cargo Heat years ago, and replaced with a 250W space heater.

It would probably do the job but I'd have to crawl around the basement to remove the thermo cube switch from the circuit.

[Tom Cherry]

15 hours ago, cbr046 said:

Or the infamous wet bay heater!

- b

Not really. Those heaters are misstated as to their load. They test 14 amps at the factory when new.  If they work, the are not designed, I think, for continuous running and you would have to Jimmy the thermostat 

look for a common hair dryer or maybe a heating pad. An incandescent light is the best as there is nothing mechanical to run or become overheated.