I just replaced mine with a Delco 28SI, it was a 200 AMP with J mount. Battery and ground wiring only.

If you have your old one off and call this place they can make sure you get the right one to convert. https://www.qualitypowerauto.com/

There are a lot of variables so double check. With the 28SI I figure I can now easily walk into any major auto parts store in the US and get a replacement if I need it.

4 hours ago, bobdinsmore said:

Thank you very much to everyone for sharing all this important information. As a result, when on the road, I now will have my water hose connected to the water inlet valve in the wet bay, with the water pump turned off.

I was thinking the same as I usually have a hose on my wet bay faucet. Another good reason to keep some water in your fresh tank when traveling.

3 minutes ago, Tom Cherry said:

This question is now being debated like Chicken and Egg...

First...review the following...

https://saft.com/energizing-iot/charging-your-lithium-ion-batteries-5-expert-tips-longer-lifespan

Then read the Victron Manual - Connecting Other Lithiums...It is a PDF below. There are two "critical" Page(s) in each and they have been printed (PDF) for those that want "the bottom line".    

Magnum says that the older chargers, specifically 5.4 or older should NEVER be used with Lithium Batteries.  Theses are the ones in question here.  Magnum did NOT start addressing Lithiums until the 5.5 Version, circa 2014 or so.

Now with the 5.5 - 5.9 versions, it MIGHT be possible to set the OUTPUT to ZERO....after the BATTERY was charged.  That in effect, turns OFF the Float Voltage... Typically 13.0 or so VDC. There is still a small amount of current...in the 2 - 3 amp range.  Note the Victron says that the FLOAT stage (if you look at the charts and understand) will be 0.05 C...certainly not a few amps.

Magnum warns owners that the misconception of using Lithiums with ANY Magnum Inverter/Charger is misinformation and dangerous...especially to the LIFE of the Lithiums.  Even  versions 5.9 or older will NOT WORK PROPERLY. As in, once a Lithium, once has been FULLY CHARGED, and then changing the Charge Percentage to ZERO % may or may NOT eliminate a tiny amount of current that just "flows" or continues to charge the Lithium.

They ONLY RECOMMEND versions 6.0 or newer, with the newer remotes for Lithiums... They also assume that an owner can properly setup or choose the correct Charging profile. In addition you need the latest version or new remote.

Bottom line...  One CAN, if desired, use any flavor of Lead Acid/AGM to start to charge a Lithium. However, one MUST monitor the current and the voltage....and then know WHEN to pull the plug... SO basically, an OWNER must determine WHEN to quit charging as the electronics that switch from "Bulk to Absorb to Float" are no longer functional.  Then, use or discharge the battery to a state where it requires or needs to "Start Recharging"

If one has a Magnum and thinks that all will work well, then continuing to do that puts the Lithiums at risk and they are ignoring the Tech Support's warnings or caveats... 

NOW, how much damage will occur and how long...  Who KNOWS.  It is like riding your brakes.  Many folks do it and they don't get as much life out of their brakes...  You can name many more situations where you ignore all the YELLOW TRIANGLES with "!" marks... and the manufacturer or the operating manual says that there will or may be consequences.

The mission of the Moderating Staff is to flag or comment or remove specific statements that are NOT SUPPORTED by the manual, the manufacturer's instructions or good or safe operating practices.

We can NOT determine the extent or the amount of damage for using the wrong charger on Lithiums.  BUT, since this site is know for complete and accurate information, we will put a NOTE or warning or remove a posting if necessary.

That's about it....

Read, process and come to your own conclusions...but any statement that says any "Magnum" will charge a Lithium battery and work "just fine" will be subject to editing and monitoring.  

Thanks for understanding....and complying.   

Charging your lithium-ion batteries_PG4-5 Expert tips for a longer lifespan _ Saft _ Batteries to energize the world.pdf 186.93 kB · 0 downloads Victron Charging Manual = Lithium Batteries.pdf 1010.24 kB · 0 downloads Manual-Connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf 283.18 kB · 0 downloads

The link you sent is for charging lithium ION. I think most in this forum would be using or considering LiFePo4. 

Just now, wamcneil said:

Yes. Temperature compensation works by raising the voltage by some small amount per degree below 70deg F. That will crank the voltage ABOVE your set point 

Understood, I assume this was for lead acid battery chemistry and I was not sure if it did the same for what ever battery type you have yours set at. I assume you are using custom or CC/CV?

1 minute ago, 96 EVO said:

Flooded lead acid.

So it does what it is supposed to do in your case.

1 minute ago, 96 EVO said:

My Magnum BTS will raise float charge voltage to 14.0- 14.1V at about freezing temperature.

But what are your settings? Battery type/voltage etc.

And what battery chemistry?

7 minutes ago, wamcneil said:

When docked, I actually don’t use the magnum  “lithium” profile for this reason (mainly…). I have the float voltage set to maintain about 50% and once the battery voltage falls to that point, the charger supplies whatever the load is. 
Something important that I forgot to mention earlier…. The battery temp compensation should be turned off, or if it can’t be turned off (ie- magnum charger), then unplug the temp sensor. Otherwise in cold temperatures it will crank up the voltage set points.

By "crank up" do you mean exceed the settings or just go to max voltage setting? I assume you are using CC/CV or customer settings.

16 hours ago, Ivan K said:

I know that lithium are happiest with below top voltage when unused but yes, the Victron charger has a default setting for lithium to include float, of course it also has custom option to change it all to whatever else.

54 minutes ago, Tom Cherry said:

Per MAGNUM, float is defined as “continuous” current AKA Voltage.  Float connotation is “LOW” current. Magnum said that in some cases, turning off or setting the charge rate to ZERO might work, but there were reported instances (Lithium batteries failed or were damaged) with just 3 or 4 amps.  Therefore, they say all their Inverters, up to a certain level should NOT be used with Lithiums.  Any voltage, sustained….as in”float” is not recommended.

See the Q&A post with Magnum’s tech support input.  This also mirrors Victron’s  FAQ.  Two stage is fine….preferably with a charger designed for Lithium….but not any float or maintenance cycle.

 

My point is Victron uses the float term for its second stage of charging. 

It basically uses bulk to 80% charge (also known as constant current) and then it goes to "float" (second stage) which is constant voltage. Assumption is this second stage would maintain charge to offset a load on system and or time out and stop charging at a certain period of time if there is no load. But either scenario would prevent the battery from being overcharged.  Of course it depends on how the user sets the parameters  for the second stage/float voltages and will vary depending the manufacturer of the LifePO battery.

My main point is that "float" may be configurable based on the battery chemistry/charger and not necessarily taboo as far as LifePo is concerned. 

16 hours ago, Ivan K said:

Interesting, even my Victron solar charger has a float of 13.5V for LiFePo4 setting and Battle Born indicates that while not necessary, 13.6V and below is OK for float:

• bulk and absorption: 14.2-14.6 volts (aiming for a sweet spot of 14.4 is recommended) 
• float: 13.6

"Float" seems to be sort of a generic term depending on the manufacturer. I assume in your case a lower voltage (float) would prevent over charging the battery while still maintaining the SOC.

1 hour ago, Tom Cherry said:

Again….my “simple” solution was that …

1… A 20 odd year old Magnum is on it’s last legs and the high dollar investment in Lithiums was NOT worth the risk of being improperly charged.

2…. The “charging profiles and parameters” of the older Magnums, like my 2009, do NOT support Lithium.  The AGM parameters are elementary and were an AFTERTHOUGHT.  So, I doubt my Magnum can be upgraded.  YES, the newer remotes, assuming the Inverter might work…

3…It was my understanding that using an older Magnum was a recipe for disaster.  Has Magnum added a function to “permanently” disable charging.  There is no “big diode” that will block the Magnum from charging a Lithium by mistake.  We have had scads of posts where even the simple “AGM” settings…failed and ruined them.

4. BTW….factoid.  If the Magnum Remote goes flaky and gets intermittent….IT WILL change the settings and it WILL reprogram the Inverter.  I had this. Magnum helped me troubleshoot it,  It was changing the bank size to 1000 AH and the various cutoff points and control parameters.  ONLY FIX….new remote.

Maybe the experts have figured out how to “FOOLPROOF” a Magnum…but from my experience and that covers maybe 50 members that I have helped and probably 25 cals to Magnum to test an idea or get information…. The Remote failing is a common thing and then Magnum says…”Don’t worry”….as in it will REVERT to the Factory Default.  The Factory Default is Bulk, Absorb, Float and the voltage will be well into 14 VDC. The Factory default for a bank is 450 AH.  So…based on what I know and have learned and such….a Magnum failure, underected…and some folks don’t understand or pay attention….WILL DESTROY or DAMAGE a Lithium bank.

NOW….that is my thiughts….so any comments on how to totally foolproof a Magnum, since you can’t reprogram the main board would be helpful…so chime in….but understand why the idiot proof or KISS, as I understand Magnums and Lithium….put in a new Inverter charger snd don’t be penny wise and mega pound foolish…

I did not realize that the Magnum products had such a bad reputation. 

I do know they make a remote that supports a lithium profile as well as custom settings to set up specific CC/CV to match your batteries.

Magnum also makes a BMK (monitoring kit) which is must if you want to get the most out of a lithium battery bank. Not a must if you are not a high demand user and spend most of your time with FHU.

As you already know I have a 2007 vintage Magnum inverter with a late release remote. 

As far as defaulting to 14V that should not bother my Lithium batteries as they are supposed to charge at 14+ and have a BMS that will stop over charging. As far as I know most Lithium batteries are similar is this regard.

I have considered getting a Magnum BMK kit but I am on the fence about spending more money on Magnum products because I know utlimately I will end up with Victron seeing how they have more control/monitoring and charging products available that seem to be more future proof than Magnum.  I am guessing all are made in China these days anyway. I do question Victrons factory support as I hear they push it all down to their retailers.

Do you still run your Magnum or did you upgrade/change to something else?

15 minutes ago, Frank McElroy said:

I think Victron now makes a dual in dual out inverter charger.  Would need to study it a bit more but it looks like it would be a direct replacement for a Magnum on a Dynasty and above coach with an inverter sub panel.

Victron Energy MultiPlus-II 12/3000 Inverter/Charger - 2 X 120V Model

Rating:

0%

Another feature that some of the late model Victron Inverters have is a hybrid mode (Power Assst) it basically allows the inverter to draw power from the battery bank if the shore power is not enough. So if you were plugged into 20 amp and needed a bit more it would make up the difference. I am sure there is a limit but if it worked well it would be good for short periods of time and hypothetically could provide a more stable 110 voltage in those situations that were pushing or exceeding 20 amps. Of course Magnum has a similar feature as well.

7 minutes ago, MJ.STIGER said:

GreyGoose i will tell you i have the same issue with bluetooth from Victrons stuff in the engine Bay. Likely due to all the metal and heat shielding. And the Lithium batteries with bluetooh BMS in the Metal battery compartment. Range is horrible. 

But i live with it and trust the $$ system that i chose to do the job. It would be nice to see the data while in motion. Now if the Cerbo has bluetooth connectivity to devices like Chargers and such. That would be one way to get the data to a display. 

I cannot make an excuse for Victron because of the location when I can buy a very inexpensive, AA battery powered temp sensor and place it in the same location and get at least double the range that the Victron has. 

10 minutes ago, wamcneil said:

IMO that's a compelling reason to upgrade to the bluetooth version of the DC-DC converter. I didn't think about that before I got the plain version and the only setting is output voltage. It would be really nice to set cut-in and cut-out voltages.

Yes, you could basically mimic the BIRD/Big boy system as far as charging logic goes. And in this case enhance the logic to support lithium. And in my mind you would not need much capacity (charge rate) for the house to chassis charging function as you should just be maintaining the chassis batteries in most scenarios. 

5 minutes ago, wamcneil said:

That was my first approach before installing a dc-dc converter. In general, I like this approach, but I wound up replacing it with a dc-dc converter.

My first attempt was to upgrade the small "smart" battery charger I keep in the garage and use that old noco "smart" battery charger zip-tied overhead and plugged into the block heater port to maintain the chassis battery. 

That "smart" battery charger would periodically get confused and decide the chassis batteries were bad and shut down. And of course I wouldn't discover this till the battery was dead... So I replaced it with a bigger fixed-mount 10a noco "smart" charger, which worked better, but every now and then would get confused and shut down... and the battery would go dead again...

If you're going to do this... don't use a noco "smart" charger. Maybe it's just my luck. I don't know. Hopefully the victron chargers won't be like that. The victron dc-dc converter doesn't try and outsmart me and it just supplies the voltage that I tell it to and that's all it needs to do. 

One problem with this setup is what happens if the chassis battery goes dead. That block heater outlet is controlled by a relay, that is powered by the chassis battery. So if your chassis battery is dead you can't use the charger to charge it...

Are you using the bluetooth Victron DC/DC charger? If so how is the range? I cannot connect to mine unless I am in the rear of the coach. I have other blue tooth devices located in the same compartment that have much better range.

2 minutes ago, wamcneil said:

That was my first approach before installing a dc-dc converter. In general, I like this approach, but I wound up replacing it with a dc-dc converter.

My first attempt was to upgrade the small "smart" battery charger I keep in the garage and use that old noco "smart" battery charger zip-tied overhead and plugged into the block heater port to maintain the chassis battery. 

That "smart" battery charger would periodically get confused and decide the chassis batteries were bad and shut down. And of course I wouldn't discover this till the battery was dead... So I replaced it with a bigger fixed-mount 10a noco "smart" charger, which worked better, but every now and then would get confused and shut down... and the battery would go dead again...

If you're going to do this... don't use a noco "smart" charger. Maybe it's just my luck. I don't know. Hopefully the victron chargers won't be like that. The victron dc-dc converter doesn't try and outsmart me and it just supplies the voltage that I tell it to and that's all it needs to do. 

One problem with this setup is what happens if the chassis battery goes dead. That block heater outlet is controlled by a relay, that is powered by the chassis battery. So if your chassis battery is dead you can't use the charger to charge it...

You are right on about the block heater but you can always just run an extension cord if you get to that point.

9 hours ago, John C said:

My understanding is DC to DC charger doesn't need to get inverter involved, you can bypass all the middleman

1) To charge the house battery from chassis battery

     a) Connect chassis battery bank to DC to DC charger,

     b) connect DC to DC Charger to Lithium battery bank

    you can setup the DC to DC charger (from Bluetooth) at certain voltage point (say 14v or so) to allow the DC to DC charger to kick in, since the Chassis battery voltage will be higher when the engine is running, it will charge the Lithium battery).

When the engine is not running, the chassis battery voltage will be low. DC to DC Charger won't charger the Lithium battery, that way it will never drain the chassis battery.

2) To charge the chassis battery from Lithium battery bank

     a) Connect Lithium battery bank to DC to DC charger,

     b) connect DC to DC Charger to chassis battery bank

    you can setup the DC to DC charger (from Bluetooth) at certain voltage point (say 14v or so) to STOP the DC to DC charger to kick in, since the Chassis battery voltage will be higher when the engine is running, it won't charge the chassis battery when the engine is running.

When the engine is not running, the chassis battery voltage low than preset value (say 14v). DC to DC Charger will charge the chassis battery from Lithium battery bank.

Because the chassis battery bank is in the same compartment as house battery bank, that should be very easy to setup.

Agree, no need to touch the inverter wiring if you are doing a dc to dc charger. I connected mine to the batteries directly with a dc breaker to protect the wiring. I am contemplating making the connection at the big boy so the Alladin will pick up the charge current. But I am currently getting the voltage reading so I can tell if it is charging or not, so it is low on my priority list.

1 hour ago, Tom Cherry said:

OK…followup.

FIRST…the 2005 Exec and the 2007 Dynasty, MAY have the same #6 board controlling the big boy….would have to check. But i think so…just different chips.

Also got some offline feedback…..one minor correction….so here is the “wrapup”

My solution, per an expert is simple and cost effective and will work….and is the EASIEST to install…. I also had a thought this morning on an improvement.

House - Replace the Magnum.  One detail was …you will need a Dual 30 IN & Dual 30 OUT. Then the wiring will be simple. You will still have the same internal inverter capacity and no mods anywhere. Four AC line moved and new DC 4/0 cabling from the New Inverter, presumably Victron, to the Lithium bank.the recommendation is a 3000 Watt unit. Basically a clone of the existing inverter/charger.

Chassis. Keep the Magnum inverter. Since it is only charging the Chassis….use the 20 Amp Block heater. Even with the charge rate set to 100%, it will only use 1,400 watts. Even a 15 amp 120 A circuit would work. Simple. NOW when  you are on Shore or Genny, the Chassis is being charged…so they will be fine.  When driving, the Alternator takes over.

BOOST.  BINGO…a Eureka thought as I woke up. Disconnect the 8 Pin connector from Board 6. Run a 5 Amp fused line from the Chassis and a 5 Amp fused line from the House. Need a simple SPDT selector switch. One side will be HOUSE and the other CHASSIS. The center or output wire from the switch goes to one terminal on the BIg Boy.. thus, you can select which side. This is important as one side may be “dead” so you need power from either. That is the SAME logic that the #6 Board has.  Then, locate, the prints tell you, the signal from the Up FRONT existing Boost switch. On the Dyansty and such, that is a NEGATIVE or GROUND. Splice into that wire and run it to the other control or coil terminal on the Big Boy.

BINGO….your front boost switch works and you go back to the RRB and chose the positive….HOUSE or CHASSIS. You now have a functional BOOST.

No need for special DC-DC chargers or maintainers. You have a Lithium House system..  The Chassis now has a premium Charger (Magnum) and will never overcharge….and you can charge with alternator whilst driving.

Boost switch works.  I’d leave the simple selector switch set for HOUSE.  You have one cable from the Lithium House to the Big Boy and one from the Chassis. The frot Boost switch is SPRING loaded…once you start…you release. No damage to the Lithiums.

If I had a Dymasty, that would be the simplest….other than the cost of the Lithiums, the only additional outlay is for a NEW Inverter….and you are replacing an almost 20 odd year old unit and now have a HIGH TECH LITHIIUM HOUSE SYSTEM…the stated objectives….plus maintain a BOOST.  Magnum eventually dies….then a much cheaper 30 - 50 Amp high end 3 stage charger/maintainer…

That’s it…and my expert mentor says it will work and is easy, relatively speaking, to install.

I think this is the solution. As an aside, I said  I was NOT a Lithium expert….but I knew the basics….some of our experts are more familiar with the equipment out there….that is where I was not….but a little thought and research….and then, I have a solution….find the right replacement House Inverter….

Edit - I missed the post from John C, it looks like he already covered this. 

Sorry I am not following on the bold. Why replace the Magnum inverter? Magnum has the capability of charging lithium (depending on the release level). 

And it is relatively easy to charge the chassis that really need nothing other than a maintance charge when the alternator is not running.

Solutions for chassis charging -

1. Solar

2. DC/DC charger from house to chassis - low amperage unit would work and with the Victron you can program it to activate at certain voltages and control the charging profile as well.

3. A small battery maintainer plugged into 110/charges when on shore power - the logic of using the block heater works if you remember to flip the switch otherwise a smart charger wired to a 110 source permanently would maintain the chassis batteries whenever the alternator is not running.

On 2/18/2024 at 6:29 PM, Frank McElroy said:

See page 92 for the low voltage high current wiring diagram.

 

 

If you need to have the engine running to extend the slide outs that's NOT how the coach was wired when it left the factory.  Someone has modified the low voltage high current circuit.  Please post a picture of the interior of your RRB (Rear Run Bay) electrical box.

Thank you for sharing the wiring diagram documents. It will save me a lot of time fumbling through the hard copies I have that do not have an index.

12 minutes ago, Frank McElroy said:

The positive cable passed through a current sensing coil just on the other side of the battery box.  Look between the large and small battery boxes where cables for the battery disconnect switches are located and you should see it.  The small wires go to the Aladdin module.

 

Perfect! Thank you so much.

Good news! It appears the small coolant leak was the issue. The alternator started working normally again today after about 10 minutes. I am cautiously optimistic at this point that it is fixed.

1 hour ago, Paul J A said:

Tom Cherry; What does/is ; MFSTS a acronym for; Chocked full of custom boards and MFSTS and other proprietary boards that are no longer available.

MOSFET...I assumed. 

MOSFET is the most common type of transistor today. Their primary use is to control conductivity, or how much electricity can flow, between its source and drain terminals based on the amount of voltage applied to its gate terminal.

1 hour ago, Tom Cherry said:

THANKS A BUNCH for clearing that up. I did EDIT my post to make it specific to your MH.  I talked to Frank McElroy off line to verify my logic and we went over the prints.  The edit is in italics....

I think that you and are on the same page....my comments are fundamental about how the system works.  The Lithium upgrade and additional equipment is a discussion point and I don't intend to go there.  BUT, it is important for folks to know how everything works and then draw up a circuit and fully understand....then make the mods and then redline or update their prints.  I often fail to do that and then say "NOW how or WHY did I do that..."  LOL

 

One additional qustion. I know that the Alladin on my coach picks up the dc voltage level from the solar panel and the house batteries at the solar controller. I verified this physically and with the wiring diagram for my coach.

Where does the Alladin pick up the DC current charge and discharge amp reading for the house batteries? 

12 hours ago, Tom Cherry said:

@Frank McElroymight chime in.  The USUAL bulk charging rate on most inverters or at least on the Magnum is up to 100 Amps.  So a totally dead house bank, with the Inverter set to 100%, then you will pump out the 100 Amps max.  Your alternator is, probably, 200 A.  

Now, pardon me for NOT understanding..….You appear to have a Lithium battery house bank.  Then, I don’t know, but assume that there is NO BIRD charging system….so your Chassis Bank is charged by the Alternator and the House by the 30 A DC/DC charger???

As long as you haven’t been charging a conventional House bank, like a Magnum would, then the Alternator would not have been abused. BUT, if you lost the conventional inverter and was using only the Alternator to charge a dead set or bank of FLA batteries, that 50% draw, plus the Chassis and the engine might have shortened the Alternator’s life…

Hope that makes sense….and folks need to fully understand the current draws for their battery banks and such…

 

Let me clarify a few things.

Inverter - Magnum MS2812 - 2800W 12/125A max charge rate

House Batteries - 230AH Lithium x 2

Chassis batteries  - 3 month old - SLA

Big boy selenoid disconnected 

Chassis batteries charge by the alternator and 1 rooftop solar panel. I have never had an issue with the chassis batteries being undercharged/dead.

House batteries charged by Magnum MS2812 - when on shore or generator power - 

I installed the lithium house batteries in early November and only charged the batteries via the Magnum inverter/charger. This worked okay but when traveling and spending a night here and there without shore power I needed to run the generator periodically to maintain the charge. Obviously when I was in a site with FHU it was never an issue. I spent the entire months of December and January with FHU.

In late January of this year I installed a Victron DC/DC 30A charger to allow me to keep the house batteries charged or at least maintained without needing to run the Onan 10K generator.

In my mind I would think the most current the Lithiums could have pulled from the alternator was 30 amps via the DC to DC charger. Based on the recent issue of the alternator not working I could tell the chassis/engine with headlights on was pulling about 50 Amps based on the charger and alladin readouts. I would think 50 amps to the chassis plus 30 amps to the DC to DC charger should not have abused a 200 amp alteranator. Keeping in mind before the lithium changeover the Big Boy was providing charging to the 800AH lead acid battery bank.

I do think the alternator is the original. It has a little over 50K, which is not a lot but I did notice the small coolant hose that is right above the alternator was dripping right into the alternator. This just started recently as I inspect my engine bay often when traveling. I will be curious to see what it looks like when I remove it and crack it open. I know alternators can take a lot of water but I am not sure what coolant could do in the wrong place. I did notice the voltage was a little off on my last leg from Mississippi to Missouri.

Anyway it all reminds of saying we used to use when we rode and modified snowmobiles. "Once the hood goes up it never stops going up". Basically saying that once you start modifying it never ends, either because we wanted more or we impacted reliability in some way.

I will go on to say, I think lithium has its place in a coach but dont do it to save money. The price of the batteries is just the start. Chargers, heaters, inverters, controls and monitoring etc. It could go on an on and for what gain? My alladin system is aging but it gives me a lot of pertinent information for monitoring the electrical systems. I can tell if the ac compressor units kick in, if the dryer is cycling properly, if the aquahot primary and secondary heating elements are working etc etc. It really depends on how you use your coach and IF you have other systems such as the inverter that is compatible and or needs replaced anyway. Dont get me wrong, I love new technology and I have worked with DC power systems for years but if I could go back in time I think I would have just replaced my 800ah lead acids with about 400ah lead acid and saved a whole lot of hassle because I really dont "need" a lot of house battery capacity based on how I currently use my coach. If you are boondocking a lot and NEED as much capacity as you can get then of course it makes more sense...then you are likely adding solar panels as well. At that point you would likely scrap the alladin and go with some other way to monitor tanks plus the electrical. 

Sorry for rambling on. I dont mean to come off as negative on lithium either. I just think people tend to overbuy capacity on a lot of things that really dont matter. But it gives them some kind of gratifcation to "have it". 

11 hours ago, MJ.STIGER said:

Well in light of this topic that has grown. I did complete my swap to Lithiums for my house batteries. 

- Installed 2 x 12 230ah lithiums 

- Removed 1 wire from Big Boy Relay to disable old school bird from charging. 

- Installed DC-DC Isolated Charger with 2x60amp resettable fuses 1 for incoming other for outgoing. 

- Unplugged Block Heater. Plugged in Victron Blue Smart Charger. Since this is controlled by switch on dash. I will use it when plugged in to shore power or Genny Running to keep chassis batteries topped off. 

( i did find out both engine and generator use chassis battery to start. Worst case if coach will not start. I should have enough poop to start generator and flip my switch to start charging the chassis batteries.) 

I will see how things go with new batteries. Dont expect any changes. But now i think i know why someone mentioned moving one of the output lines on the Inverter to power the AC units. Those dont seem to run when on Battery. Something to dive into and tackle down the road if needed. 

What is the plan for charging the lithium house batteries? Does your current inverter/charger have a CC/CV or custom profile to adequately charge lithium?

Will you be traveling and or operating in colder climates? The reason I ask is lithium batteries need heat/warmed when it gets below 35 degrees.

Also if you have a solar panel that may be enought to keep your chassis batteries topped off. It certainly has for me at least.

28 minutes ago, Frank McElroy said:

Don't know if this was your situation but pne thing to keep in mind is that the engine alternator system was basically designed to maintain house and chassis battery power.  If you used the alternator to in effect bulk charge house batteries you will significantly shorten the life of the engine alternator.  Bulk charging house batteries is to be done with the generator and the inverter/charger.

It is a 30 amp dc to dc charger so I assume it should not have been over loaded regardless.

I also just noticed today that there was a small coolant hose located right above the thermostat housing that had a very small leak that was dripping right into the alternator. I tightened the clamp today but I will find out more when I remove the alternator.

On 2/16/2024 at 10:00 PM, MJ.STIGER said:

Never thought about 24V. but for my simple upgrade 12v it is. 

I will be completing the swap tomorrow on my 05.  Installing a DC/DC converter and a Charger for the Coach Batteries from the Engine heater plug. And will be removing the Trigger Wire on my Big Boy Relay. 

I will think it though if i change out my Inverter Maybe do another upgrade to 24v. But i dont boon dock much and the wiring is in place. 

Good luck! I found out yesterday it was good to have a DC to DC charger on board. I was just ready to pull out of a campground and my low battery light went on. A quick check with my voltmeter verified that my alternator was not charging. I flipped the 30 amp DC to DC charger wiring to charge my chassis batteries from the house and in parallel with a 110/20 amp charger running off my block heater switch I was able to generate enough charging to complete my 400 mile trip home.

Is it a coincidence that my alternator went out about 1000 miles after adding a DC to DC charger?

48 minutes ago, JDCrow said:

Well I’m not sure how you charge a battery from two different sources at once. I mean, I never stick 2 chargers in a battery. 
 

I don’t have two bad a range in the charger, but will be upgrading to the touch screen inside this spring. 

Two chargers in parallel is theoretically possible and is not uncommon in large dc power plants. Also many DC to DC  chargers advertise that you can you multiple units in parallel to increase capacity.

6 hours ago, JDCrow said:

Yes, but what does your Xantrax have? Sorry I not responding quickly. If you quote me in your response, I’m alerted that I need to get off my butt

So the only issue I have run into with the DC-DC charger is for those who run their genset while underway to power the ACs. You will have to turn the Dc-Dc charger off if you run the genset and engine at the same time. You would be essentially charging the batteries from 2  different sources at the same time. My Victron shut completely down and stated I had a “ripple” which I dug into but really only understood that the two chargers interfered with each other and the System just shut down to protect its self. 
 

Turning Dc~Dc off is easy in the Victron App

Disappointing that the two Victron chargers do not play nice with each other. I will say that I am very disappointed with the bluetooth range on the Victron DC to DC charger that I have. I have several battery powered bluetooth temp monitors that have much better range.

2 hours ago, MJ.STIGER said:

That makes sense the wire that triggers the relay. So Everything  is intact incase you had to revert. Smart thinking. I think was over thinking this. 
Did you change out your Inverter/Charger or are you using the Xantrex one that was existing on your coach? 

 

I am using the factory Magnum MS2812, with a late release ME-ARC remote that includes a lithium as well as CC/CV and custom battery profiles. But I am not happy with the charging cycles and plan to add a Magnum BMK when I get home from Texas in a couple weeks.

I also took the factory solar controller and wired it so it only charges the chassis batteries.