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Topic: Changing flooded lead acid batteries to lithium batteries (Read 2190 times) previous topic - next topic

Re: Changing flooded lead acid batteries to lithium batteries

Reply #25 –
My Victron equipment has been reliable and I like the way it talks to one another and has a feature rich app. I have two B2B chargers, shunt, charge controller and battery smart sense that all show up on one screen in the app. I was able to tailor my solar charger to the exact specifications of my house batteries through the advanced settings.

Lots of good videos on YouTube and many fellow rv owners using the equipment. I like the way you can start off rather simply but over time expand into a sophisticated system that integrates well. There are also firmware updates without charge delivered through the app. I recommend that when you add solar you leave yourself some "room to grow" when choosing a solar charge controller.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Changing flooded lead acid batteries to lithium batteries

Reply #26 –
I have 3 charge controllers. Each handles a pair of panels. This keeps the cable loads low and will still charge if one set has a failure.
It's a. Little messy but runs well inside of the load parameters.  The 2300 watts runs the li iron batteries at as high as 90 amps 12 volt.
 I seldom plug in.

Re: Changing flooded lead acid batteries to lithium batteries

Reply #27 –
So I talked to Elliot's guy Dan Henning with Rv Solar Consulting. He is going to design my lithium solar system and doing it in 2 phases. FIRST PHASE Lithium batteries, victron b2b 30amp charger, victron bmv-712 smart battery monitor. SECOND PHASE victron 3000 MultiPlus II inverter charger, solar panels, 2 solar charge controllers etc. I discussed with him the possibility of running my front rooftop a/c off the inverter going down the road. He said it was possible but would probably dip into the batteries some. So would work 4 or 5 hours depending on solar input. I can always run the generator as needed. The thing that he told me that I don't fully understand ,and hope you guys can set me straight. Is that with the victron 3000 multiplus II inverter all ac power for the coach passes through the inverter. I understand that. The part that i can't quite get my head around is he said that the generator power because ( I'm probably going to butcher the terminology) the 2 hot legs off the generator are in phase instead of out of phase. That the victron 3000 multiplus II would only pass through 1 leg off the generator. Which would cut the usable output of the generator in 1/2. Which I think is unacceptable. He said there are some work arounds but we didn't get into the details. Please help me understand what needs to happen for this not to cut my usable generator output in 1/2. Sorry this is so long. I know Dan will explain it to me more, but I know a lot of you have already plowed this ground.  Thanks Tom
Tom and Michelle 2004 U270 36WTFS

Re: Changing flooded lead acid batteries to lithium batteries

Reply #28 –
I watched a YouTube with RVing with Tito where he had the same issue and installed a jumper, it kept popping a breaker with to much draw on one side
1999 36 ft U270
Build 5465

Re: Changing flooded lead acid batteries to lithium batteries

Reply #29 –
Quote from: T and M Long –
So I talked to Elliot's guy Dan Henning with Rv Solar Consulting. He is going to design my lithium solar system and doing it in 2 phases. FIRST PHASE Lithium batteries, victron b2b 30amp charger, victron bmv-712 smart battery monitor. SECOND PHASE victron 3000 MultiPlus II inverter charger, solar panels, 2 solar charge controllers etc. I discussed with him the possibility of running my front rooftop a/c off the inverter going down the road. He said it was possible but would probably dip into the batteries some. So would work 4 or 5 hours depending on solar input. I can always run the generator as needed. The thing that he told me that I don't fully understand ,and hope you guys can set me straight. Is that with the victron 3000 multiplus II inverter all ac power for the coach passes through the inverter. I understand that. The part that i can't quite get my head around is he said that the generator power because ( I'm probably going to butcher the terminology) the 2 hot legs off the generator are in phase instead of out of phase. That the victron 3000 multiplus II would only pass through 1 leg off the generator. Which would cut the usable output of the generator in 1/2. Which I think is unacceptable. He said there are some work arounds but we didn't get into the details. Please help me understand what needs to happen for this not to cut my usable generator output in 1/2. Sorry this is so long. I know Dan will explain it to me more, but I know a lot of you have already plowed this ground.  Thanks Tom

Two things to keep in mind, one is if you have the second transfer switch nothing goes through the inverter when on A/C power. Second thing is the factory wiring doesn't put both legs through the inverter, the A/C units are on a separate leg than the inverter. You would have to rewire to get the A/C to come out of the inverter. Others have done it. Keep watching for replies from members that have the multiplus I don't.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Changing flooded lead acid batteries to lithium batteries

Reply #30 –
I installed my multiplus in between the transfer switch and the breaker box. The original inverter is disconnected and removed. It passes both legs when on shore power, but I can't say I've actually checked when on generator power. I would keep the multiplus in the circuit at all times. It will auto transfer to the inverter function if shore power is lost or dips. It can also split the load between the batteries and shore power/ generator if needed. It's a really nice unit. I love mine.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Changing flooded lead acid batteries to lithium batteries

Reply #31 –
I checked mine this morning and the generator powers both legs of the AC.  The standard transfer switch handles the shore power/generator connection and the Multiplus switches to inverter mode to maintain power to the coach while the transfer switch is changing over. I can run everything without interruption while swapping between shore power and generator without issues. Depending on your HVAC load, you might get enough power out of the alternator while the engine is running to support that without needing to run the generator.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Changing flooded lead acid batteries to lithium batteries

Reply #32 –
Kgrover thanks for checking that out on yours for me. What generator do you have in your '91? Not sure if that matters or not. I did some research on the subject and what Dan told me seems to have validity. I was reading on a victron forum there was a lot of discussion about it. Did not see an easy solution there was talk of adding transformers, and such. Really getting out of my comfort level, of knowledge.
Tom and Michelle 2004 U270 36WTFS

Re: Changing flooded lead acid batteries to lithium batteries

Reply #33 –
Additional questions for consideration.

Generator power thru Multiplus only recognizing one hot leg.

1.a.  What we don't understand what limitations in real world scenarios, such as, running both ac's and charging batteries, at 120amps (potentially) or similar scenario...would one leg of generator be able to power all that?

1.b.  Would running that large of off-balanced load between the two lines, cause any problems with the generator or any other components?

1.c.  We are just trying to understand what the limitations of the system would be in real world use, with the solar added to the equation.

2.  Would there be any additional equipment that might help in the scenario?  We do not HAVE to run one air conditioner thru the inverter, just would be nice, but if it really simplifies things, we can choose to design the system with that in mind.

3.  If all the power for the motorhome is run thru the multiplus as pass through, and only one leg of the generator is recognized, would all the electrical system work, but only have 5kw or less of usable power (off 10kw Powertech)? And does the solar power "stack" with the generator to "add" that additional wattage?
Tom and Michelle 2004 U270 36WTFS

Re: Changing flooded lead acid batteries to lithium batteries

Reply #34 –
Keep in mind that unless modifed substantially, shore power and generator are direct to the Aircon/heat pumps, washer drier, and electric element on the Aquahot (if so equipped). So the inverter is not involved in any way with those heavy loads. I do not believe it true that those loads are passed through the inverter. I think one of my ACs is on leg 1, one is on leg 2 (I'll have to look to make sure my memory is correct).

The inverter does power the convection microwave (heavy load depending on use) and all 110 volt outlets (except washer/drier, and there "may" be 2 choices for plugging in fridge/ice maker (inverter or not).

Check your breaker panels. One panel for all loads, and one subpanel will show you exactly what the inverter powers.

I have the Victron 3000 MultiPlus II

Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Changing flooded lead acid batteries to lithium batteries

Reply #35 –
Dan. Thanks for the input I was looking at what I have; the air conditioners are on separate legs. It is very possible that I am confused. I might have complicated the conversation I had with Dan  at Rv solar consulting. When I asked him the possibility of running the front air conditioner off the multiplus, with the solar and b2b charger. It might have taken the conversation down a rabbit hole I don't need to go down. We were talking about my desires for my system, so he could design something around that. I emailed him the same questions I posted on here. Waiting for his response.    Tom
Tom and Michelle 2004 U270 36WTFS

Re: Changing flooded lead acid batteries to lithium batteries

Reply #36 –
After learning a lot in a few days I have found out there are a couple different ways to install the Multiplus II inverter. After talking to Mike ( Pamela and Mike) , Elliott and texting with Roger I am more educated, than before. Also have done a lot of reading on this. I will wait till  I get my plan and go from there.
Tom and Michelle 2004 U270 36WTFS

Re: Changing flooded lead acid batteries to lithium batteries

Reply #37 –
Here's the tag on mine generator.  I'll have to check the voltage and see if I get 240v from l1 to l2
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Changing flooded lead acid batteries to lithium batteries

Reply #38 –
I checked my setup and I have power on both L1 and L2 at all times. I have 240v from L1 to L2 when running on shore power or the generator. When the Inverter is running in inverter mode and there is no external power, it does not have 240v. But I do have 120v from L1 to N and L2 to N. So the Multiplus II does not provide 240v but it does power both legs.

My inverter is not replacing the existing one. The original inverter is removed. My wiring goes from the Transfer switch -> Watchdog surge protector -> Victron Multiplus II -> Breaker box. I can run any 120v circuit anytime no matter what power source is available. It's usually just keeping the fridge running, but I have run the AC unit while driving.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Changing flooded lead acid batteries to lithium batteries

Reply #39 –
Jumping in here.  I am in the middle of a major 920 amp hour lithium/power distribution upgrade.  On the B -B issue, Victron has a 50mamp coming out in April... smaller, more efficient, less heat.... I couldn't wait so I went with a Sterling 70 amp that has reverse charge capabilities.  They have units that go as high as 200 amps if you have the alternator to support it.  Sterling is an old UK company (with distribution in the US) that started as a marine electronics supplier.  Now, many NA RV manufacturers use their stuff.  I had their 30 Amp B-B in my last coach.  Not quite as sexy as the Victron, but very well made, great, direct from the owner support.  Because of a certain level of paranoia, I installed a new 200 amp Victron FET isolator....just in case.  cheap,insurance at about $120.00.  The B-B is being installed between the house side of the isolator and house side of the boost relay...replacing the short piece of 6AWG.  A 100 amp breaker will be in front of it and another 100 amp breaker will be installed on the far end at the new power/fuse distribution panel.

I am completely undoing the FT "mess" at the house DC panel in the bay.... No protection of any sort...can't live with that.  All major feeders and distribution will be isolated and fused as it should be.  Each battery (4) will have separate terminal fuses and identical length + & - feeders to common buss bars.  All batteries will be paralleled to maintain battery to battery balance.  Battery buss output will run through a 500 amp ANL fuse and then to a "whole house" disconnect and then back to a 1000 amp buss with 6 high current fuse positions....

As a side note, there is good reason to use the Victron 1000 amp smart shunt....it has the ability for multiple connections on the outbound side, thus eliminating the need for a separate negative buss bar beyond the shunt.

Lots more to this, but as an electrical engineer who works with the NFPA and NEC, it's getting built "by the book".  And just an FYI, there is an actual section of NFPA 70 (ie NEC) that pertains to RVs and RV parks....Article 551 if you are interested.

I will post some pix in the coming days of the panel and process/progress....  Questions/comment welcome.  PM for deep details if you like...

2002 U320
3620 PBDS
Build 5985
2021 Equinox Toad
Motorcade 19006 & all those "other" clubs too!

Re: Changing flooded lead acid batteries to lithium batteries

Reply #40 –
rusczyk56, thanks for the lead on the Sterling B2B chargers. I see that they have a 120A one.  With the big alternator in my coach and the second AC wired up to an inverter I was needing to put around 120A into the batteries while going down the road.  I  have been trying to figure out how to go about getting enough amps into the batteries going down the road and it looks like that will work. Have not done much research on them but it looks like it can be used as a battery boost and when on shore power it can keep the chassis batteries up.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Changing flooded lead acid batteries to lithium batteries

Reply #41 –
Thank you for the responses to this thread.  I will Pm you in the near future. So it is my understanding at this point that A) you can remove the old inverter and replace it with a victron multiplus. Wired as it was from the factory. You would  be able to run everything your current inverter runs now. The generator would run as it did from the factory. No problem.  B)  If you want to run all of your 120 volt loads through the multiplus.  As pass through power and take advantage of all the capabilities the multiplus has to offer. Mainly power boost feature. You have to wire it differently and upgrade the size of the wire going from the inverter to the main panel box as the wire is under sized I believe 10 gauge. Evidently wiring this way is where you would run into the problem such as running an a/c off the the inverter without upgrading the wire size. Also where you would run into the problem with the generator. That I mentioned previously. I still have much to learn and I realize I can't explain the details as well as I would like. I am really working on educating myself as much as possible. Before I get knee deep in installing the inverter and solar aspect of this project. There is some description on The Victron Forum about the problem with the multiplus not recognizing both legs off the generator.
Tom and Michelle 2004 U270 36WTFS