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charging battery

BlueSolar MPPT 75/15 - strange behavior after update (1.50)
  • BlueSolar MPPT 75/15 Charge Controller 12/24V 15A
  • 2 * Solarmodul 100 Wp 52 x 115 x 3,5 cm monokristallin
  • 2 * Varta Professional Dual Purpose AGM 840 095 085 (LA 95)
  • Pössl Camper

Dear Victron fans,

after the last update of the firmware to 1.50 and with factory values, I noticed a strange bulk behavior: The curves are rising and falling (jumping) in seconds, sometimes down to zero (see screenshots). As a result, it took a long time to charge the battery. Oddly enough, the charging process seems to be normal when the engine is running and the battery is being charged (at the same time).

  • does anyone know the phenomenon?
  • maybe it has something to do with the upate?
  • maybe this is normal?



  • the engine is off


  • the engine is running


H.E.K asked

0 Answers

Charging batteries,service,start,thruster


Hi everybody , above is sketch of charging circuit on my boat (without breakers , fuses etc..)

I would kindly ask for some advice.Service battery is AGM and start and thruster normal lead acid high current batteries.

1) is it OK to use alternator(via argofet) and solar charger together(especially on AGM battery) ?

I am planning to add one more 220Ah battery in parallel for service and install more solar panels(about 500 - 600W in total)

2) is it OK to use same 3 years old battery with new one , or should i install both new batteries?

3)Would it be better to use GEL batt instead of AGM for service use?

4)I have to install higher power solar charger, should i charge only service batteries , is it mistake to charge start and service from solar?

5)Is it OK to charge GEL batt with alternator(via argofet) , or with alternator and solar together?

Thanks a lot for any help

mikula asked

0 Answers

Question on Wiring Diagram for Phoenix Smart IP43 (3)

I'm planning to use a Phoenix Smart IP43 with 3 Outputs to charge one starter battery, one service battery and a bow thruster battery. There is already installed a Argofet 100-3 to charge the batteries with the alternator.

There is a download of a sample wiring diagram for the IP43 which comes very close to the one that i need.

But there's one thing which is not clear to me:
In the wiring diagram the Phoenix Charger is directly connected to the 3 Batteries but the Outputs of the Argofet are connected behind the Main Switches of the Batteries, so that they are disconnected when Main Switches are off.
What is the sense of wiring it in that way? The Outputs of the Argofet could also go directly to the Batteries, or not?

The background is that the connection from the Argofet to Starter and Service Battery would only be an few centimetres but when connected behind main switch it will be much longer.

Many thanks in advance for answers.

mjuergens asked

0 Answers

Alternator Charge Current Estimate at 13.8 Volts


I am planning the upgrades to lithium for my motor home. And I'm trying to estimame and budget for whether I NEED a battery to battery charger or if I can get away with just alternator charing through the BMS.

Looking to start with:

1 x Victron Lithium 12V - 100Ah Smart and CL BMS 12/100

I know i can limit the current using fuses on this BMS to protect my alternator.

Reading the litrature for the battery it recomends charge voltage of 14V to 15V. 14.2 being needed for cell ballance.

I'm only getting 13.8 volts from my alternator and I'm worried I wont be able to charge (or top up ) by lithium batterys without adding a B2B which can boost the voltage.

My question to anyone who can help me is:
My alternator only puts out 13.8 volts.

Will I still be able to charge the lithium pack at a sensible rate with a marginal voltage difference and below the recomended charge 14.0 charge suggetion?

I'd like to be able to top off the batteries at 50Amps from the alternator - is this feasable without boosting the voltage using a b2b?

Not knowing the internal resistance of the lithium pack I can't calculate the sort of charge current I could expect.

Does anyone have some first hand guidance of charging from alternators of lower voltage ?

thanks for the help



TonyJobson asked

0 Answers

Victron Phoenix Smart IP43 12/50 (3)

Can I charge lithium and AGM batteries simultaneously or do all the batteries have to be lithium or AGM/Gel etc? I have good AGM but want to start replacing with lithium as they fail. I am looking for a charger that will allow me to do this.

Barry Venter asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

How to force charging batteries at night from grid on an EasySolar with an ESS configuration ?

Actually, my problem was that my SOC was toping at 89% and the EasySolar didn't accept to charge the batteries anymore.

After a little discharge, (SOC at 84% this morning) it finally accepted to charge them.

Now the question is "Why does the EasySolar don't realize that the battery is full ?"

Is there a way to reset the soc at 100% ?

Please tell me if I am in the wrong way of thinking.

Config : EasySolar 3000VA 48V - 500AH LeadAcid Batteries - 2000W solar panels - set up 1 month ago.

StephDuyns asked
Girbar answered ·

4 Answers

Connecting Victron BlueSolar PWM Light 12/24V-10A input to AC/DC converter

I tried to connect Victron BlueSolar PWM Light 12/24V-10A input to 24V,5A AC/DC converter, instead to solar panel.

I came upon a problem. My 12V,40Ah battery is being charged really slow. After 4 days, it was still charging in bulk mode. It should be charged in 8h or so.

Is it even possible to quickly charge battery this way?

Vladimir36 asked

0 Answers

Can PV power from a grid tied inverter be regulated to optimally charge batteries if connected on AC input.

Good Day

I have been looking through the various manuals and assistants on the Victron website and forums but i am still not sure if the configuration i desire is achievable .

I currently have a Solaredge 3 phase grid tied inverter which has 7kw of panels connected to them. This was my initial setup which did not have any battery backup and any additional Pv produced was fed back into my local grid for which i received a credit . ( installation was November 2018).

Load shedding has become a serious issue in South Africa and the need for backup became increasingly important. I then installed 2 x off grid 5kva Axpert inverters with an additional 6kw of panels and 7 x 3.5kw pylontech batteries (24.5kw in total ). We separated all loads requiring backup to a single phase and the inverters were connected in parallel. Pumps , underfloor heating , water heating elements are connected to the other two phases still.

To cut a long story short i was extremely disappointed with the inverters performance and functionality and i have decided to replace them with 2 x Multiplus ii 5000 inverters. I will purchase the other additional items like the MPPT , cables , ET340 meter, etc. From my understanding the Cerbo ( still due to arrive in SA by end of May ) would be used to control the whole system and everything links into them.

Would the Victron system be able to differentiate between Power that is bought from the grid and PV power from my Solaredge inverter on the AC In side of the Multiplus to regulate the amount of power used to charge the batteries . Ideally no power from the Solaredge inverter should be fed back into the grid if it can utilize the PV power more effectively to charge the batteries.

I have noticed that the Victron inverters can receive PV data from the Solaredge inveter. Can this info be used to optimize self consumption or would the data be purely for viewing .




Khalied asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

Why does charging voltage need to be higher in lower temperatures for lead-acid batteries?

I came across this blog entry which basically says that, for lead acid batteries, lower temperatures require higher charging voltage. Can anyone please explain why this is true, or point to an authoritative source?

I did ask this question on Chemistry SE a while ago, and those guys seem to be of the opposite opinion: higher temps need higher voltage.

Intuitively I disagree with them and agree with the blog post: lower temps need more power to move molecules around, remove sulphate crystals etc. But I seek a definitive authoritative explanation.

Greendrake asked
Daniël Boekel (Victron Energy Staff) commented ·

1 Answer

How to download data from SmartSolar MPPT 150/70-TR VE.Can?

Sinc I could not use the VictronConnect on Android 4, I had also problems with my Huawei Y6s because it did not show the dialog, where I have to enter the PIN... Was solved, by changing the text size!

OK, now I can see all data from my SmartSolar, but how can I download it to my Huawei Y6s, Lenovo TAB4 8 or my Thinkpad T400?

Thanks in advance


linux4michelle asked
linux4michelle answered ·

1 Answer

Mppt 100/15 charging problem

Hi Community,

I have some problem with my new Mppt 100/15 blueSolar charger. The charger doesn't charge my battery ? Can you help me ?

Follwing parameter.

2 Büttner Panel MT SM 110 MC

1 Battery 180Ah Lithium LiFePO4

1 MPPT 100/15 BlueSolar charger

Solar volt: 20,93 v

a = 0a

Battery volt = 13,19 v

setting in mppt charger: i use the default profil: Lithium Iron Phospate (LiFePo4).

12 Volt setting

max ah: 15a

The last 3 days, my camper war parked in sun.. But the battery is not load for a second.

Thanks for your help


spokiter asked
spokiter answered ·

3 Answers

BlueSolar PWM-Light doesnt auto reconnect

Dear Victron support,

I have set the BlueSolar PWM-Light to Load = battery following (mode C).

After the battery is <11.2V the load is disconnected, but when the battery is > 13.1 V its not automatically reconnected.

How is this possible?

nelis1990 asked
nelis1990 edited ·

0 Answers

ENtstörung Victron 75/15 MPPT

Guten Abend,

ich Betreibe ein 120W Modul und eine 100Ah Solarbatterie gemeinsam mit einem Victron 75/15 SMART Laderegler. Den Lastausgang habe ich auf einen Philipi Sicherungskasten aufgelegt. Hier gehen dann entsprechen die 12V Steckdosen, Lichter, und Autoradio ab. An der Steckdose habe ich heute eine Verstärker (Teufel Rockster) angeschloßen und über diese Verbindung wurden sehr starke Störungen eingeschleift das dieser erst brummte und dann anschließend abschaltete. Gestern bei bedecktem Himmel gab es keinerlei Störungen bei gleicher Konfiguration. Kann es sein das auf dem Lastausgang nicht entstört ist und das pulsen der Batterie hier übertragen wird?

Gestern war die Last höher als die Einspeisung am Solarmodul. Ich überlege gerade hier einen großen Kondensator aufzuschalten um diesen Lastausgang zu entstören. Kennt jemand diese Phänomen oder hat schon einemal jemand den Lastausgang im Oszi betrachtet?

Andere Vorschläge?

Liebe Grüße


PV_AxElli asked
PV_AxElli answered ·

2 Answers

Is it possible to connect two DC chargers in series to charge at a higher voltage?


Is it possible to connect two 24VDC chargers in series to charge a battery bank at 48VDC?

There are apparently no 48VDC chargers with Universal input of 90-265V, 50/60Hz.

I thank you in advance for your assistance.


Blue sails asked
Harold answered ·

1 Answer

Why MPPT is overcharging

MPPT 75/15 overcharging

It was working all fine for 3+ months but then I saw that it charges the battery in 16v+ range. Few days before that I used the same controller to charge another battery and then switched back to the main battery. I don’t know if that triggered some problems because it was cloudy on those days.

But now, if it’s sunny, it goes to 16v range and always stays in a BULK mode (flashing fast), never going into Absorbtion or Float. I tried disconnecting everything and connecting to another Victron battery and the same thing, as if the charger thinks that the batteries are 24v, but they are 12v. Could that be a problem? I don’t have a dongle to check it out, can’t buy one because shops are closed. Is there anything else I can do to find the cause of the problem or temporarly fix it?

My set up:

2x 120w solar panels connected in series.

MPPt 75/15

130ah battery.

As I said before, it was working perfectly for few months and then suddenly the problem occured. Currently my solution is to disconnect the panels if its a sunny day, but my campervan fridge drains it quite fast. I tried partially covering the panels but strong wind blows anything off the roof…

Thanks for help.

Andzei asked
Andzei commented ·

4 Answers

LifePo4 Charge Profiles

Hello, I'd love to get some input from the community regarding how they are setting their charge profiles for LifePo4 batteries across Victron equipment.

The standard profile seems to be; Absorb - 14.2V and Float 13.5V - These seems to contradict various articles and research I have done.

Any input would be appreciated.

mrdanielmh asked
klim8skeptic answered ·

2 Answers

BMW i3 Charging on an Victron Quattro + ESS LifePo4 system

Hi everyone,

My about to go live system, is comprised of a Victron Quattro 48V/8000VA + Smart Solar MPPT Charger 250/100 MC4 and 24KWh of LifePo4 batteries. My question is;

What's the proper way to configure my system, so that during Winter, the i3 wont use stored energy from the ESS Batteries to charge it self ?

In other words; its ok if during summer it charges from the ESS available power but during winter it should charge exclusively with evergy from my electricity provider.

would love to ear your thoughts. Thankx !!

Cadoxa asked
DayAndNight edited ·

4 Answers

multiplus 3000va / 12v inverter/charger / generator charging leisure batteries

Have a 3000va 12v Multiplus inverter / charger. Looking to purchase a 3kw generator as back up power supply as well as charging for batteries. Recommendations of generators that will work happily with multiplus.

Peter Groves asked

0 Answers

Quattro Stops Charging at 75%

I have a 5kW Quattro on my sailboat, along with a MPPT 150/100, for my 1200Ah 12V lithium battery bank. For a while now, the charging, regardless of source (generator, shore power, solar) will stop at 75% when the battery voltage is 13.5V. Previously it would charge fully. The battery bank capacity and charged voltage (14.2V) are set correctly in the VictronConnect app. Any ideas what I can try? Please let me know what other information I can provide about my system and settings to help answer this question. Thanks!

svgalatea asked
JohnC answered ·

1 Answer

How can Multiplus 1 be used to increase charge power in ESS system with Multiplus 2 and GX

Hi, I have installed an ESS system with MP2 5000VA/48V, 40kWh battery bank and 5kW PV solaredge inverter on AC-IN. I have an additional MP1 5000VA, how can i use this only as charger to increase the charge power of the system up to 5kW?

I cannot find any information resources, i know that those different models cannot be used in parallel. I know that i could set up an additional gx and make an independet addtional system, but i am looking for a solution as one system with one monitoring?

thank you for your help.

gnagflow asked

0 Answers

Different charging sources

I have a Victron MPPT 75/15 with a 100W solar panel and 66Ah (2x33 actually) lithium battery. All works fine. I'm about to install this in an adventure-style trailer (based on small utility trailer with tent on roof of trailer). I'm driving a Golf Bluemotion w/ start-stop (i.e., bigger alternator, but voltage all over the place). I'm looking to be a bit sustainable and would appreciate any feedback on a couple ideas:

1. Power from the car should run the fridge and give some charge while driving. Power via the trailer wiring harness is 2.5mm2 (14 ga) and I'd like to limit current to say 4A (~50W). For sure there are DC-DC chargers out there that will manage this for a couple hundred $ or € or £ (Victron indeed makes a nice one), but my needs (current speaking) are so limited. On ebay, there are dozens of CC/CV boost converter starting at $5 if only wanting 2A. For $20, easily up into the max 6A in / max 100W out range (and they're adjustable, so I can choose the amps I'm comfortable with). I don't see these being discussed much in these circles... is it just because their power is too limited for most people?

2. While the power from the car (above) would keep things running + charging while I'm on the road, I would like the option to charge from AC at a campsite / in garage. I've recycled an old 250W desktop computer power supply (PS) into a 12v (18A) DC power supply. Again on ebay (etc.), there are cheap 12-24v 10A step up converters. This seems like a perfect fit for me. Am I missing something fatal?

3. While a CC/CV boost converter can directly charge lithium batteries without a charge controller (if I had lead acid, I'd worry less about cost of screwing up), is there a reason why both the power from the car (3A@20v) and the power from the PS (10A@24v) couldn't both go through the MPPT 75/15. All within MPPT ratings, and I just need to give some thought as to whether I need a 3-way switch (to ensure only 1 charge source is ever connected) or use diodes to prevent current randomly going backwards into places it shouldn't (e.g., don't want to have my solar panel pushing current back into the car and screwing up electronics) Am I missing something fatal? If I didn't have a 3-way switch and had the craziest situation where I had my 100W solar panel out (say 5A@18v), car running, and trailer plugged in for AC charging, this is effectively like the "can I hook up 3 unmatched solar panels in parallel" discussion, no? (I'll read more into this one, but I think 16-20v from solar panel and 10A@24v from the AC charging is too far off? i.e., equivalent to very unmatched solar panels...)

I know a few questions. Thanks for any input!

archean1 asked

0 Answers

Can MultiPlus Compact 12/1600/70 firmware be updated through VE.Connect?

Hello everyone. I have a MultiPlus Compact 12/1600/70-16 on firmware version 154. Is this firmware out-of-date? Can this Multi's firmware be updated using VE.Connect, or do I need to use the (deprecated, dangerous(??)) VEFlash method?

Reason for wanting to update:

In addition to the Multi, the system has a BMV-702, CCGX, and 2x MPPT 100/50. The MPPTs charge a 12 volt ReLion lithium-ion battery bank from two separate solar PV arrays.

I would like to tell the MPPTs that the battery voltage is what the BMV-702 measures, and not what each MPPT senses at its "battery" output terminals.

This is because in bulk charging there is a discrepancy of as much as 0.7 V between MPPT and battery voltages, depending on charging current. Under float conditions, the discrepancy tends slowly towards 0.1 V. The voltage drop from the MPPT output terminals to the battery's terminals is presumably due to the cabling, fuses, and isolator switches, none of which can be changed.

I want the MPPT to receive battery voltage data from the BMV-702 (or maybe the Multi) to solve this problem.

I read here that I can do this with the CCGX using DVCC and SVS. However, when I tried this I got an error message saying that there is a firmware incompatibility issue. Since all firmware in the CCGX, the BMV, and MPPTs is up-to-date I conclude it must be an issue with the Multiplus' firmware.

Any help greatly appreciated!

glasses asked
ejrossouw answered ·

1 Answer

Simultaneous charging with a grid tied PV inverter & MPPT charger in parallel possible?
Page 40 of the Wiring Unlimited guide states:

Voltage sensing in an Energy Storage System (ESS) with DC Solar

In an ESS system with an MPPT the charger of the inverter/charger is disabled.
This is because the MPPT charges the battery and excess solar power is being fed back into the grid. This process is controlled by the CCGX. To make this work, the CCGX will set the MPPT at a higher DC voltage than the inverter/charger’s DC voltage.

Assume there's a grid tied PV inverter connected to a MultiPlus II on AC-Out-1 with an MPPT charge controller connected to the same MultiPlus II. We'll use this diagram as an example:


Does this mean that the power output from the grid tied PV inverter will not be used to charge the batteries and only the power output from the MPPT charge controller will be used to charge the batteries?

As far as I can tell, the ESS guide doesn't make any mention of this inability to provide simultaneous charging from MPPT's and other energy producing units connected to the MultiPlus, in fact, it seems to imply that this is possible?

gyrex asked
Margreet Leeftink (Victron Energy Staff) answered ·

2 Answers

Argo FET 200 capacity

Hi, In my boat I am adding a Delco 28Si alternator which supposedly is capable of giving up to 250A. I could reduce its output to around 180A-200A, but it might when starting and for a couple of minutes nevertheless yield up to 250A. Is the Argo FET 200-3 capable of handling this current? I.e. is it OK to exceed its rated specification of 200 A for either longer or shorter periods?

There will be three battery banks connected: 600 Ah LiFePO4 House bank and 200 Ah +105 Ah AGM banks for thruster and starter, respectively.

Thank you.


Eirik asked
Eirik edited ·

0 Answers

Multiplus-II in Hub-1-3 stuck in Float

Der All,

following issue,

My AGM 48 Volt battery system is not following the routine charge routine (Bulk-Absorb-Float) but basically stack in float mode and the corresponding voltage.

Maybe someone can tell me why the system is not starting the day in the normal bulk mode and increasing the voltage until absorption voltage is hit?

The weather is usually allowing this voltages and the batteries are in the morning down to SOC 70%.

In ESS the system was working properly, in HUB 1-3 it isnt.

My system:

My Multiplus-II in Hub-1-3 configuration (normally disconnected from the mains).

Previously I used ESS but I prefer islanding due to legal reasons, In ESS i did not have these problems.

Venus GX, AGM 48V 6 Kwh battery system.

FYI i played already with the "repeated absorption interval" setting, no changes.




SeemannJanek asked

0 Answers

On the MultiPlus II, is it possible to completely disable charging batteries from the grid and only use solar?

I'm currently planning the following configuration below


In this scenario, is it possible to completely disable charging batteries from the grid via AC-In and only use the solar panels connected to the BlueSolar & excess power from the PV grid-tied inverter connected to AC-Out to charge the batteries?

Many thanks in advance for any help.

gyrex asked
Rob Duthie commented ·

2 Answers

Can anyone explain synchronized charging?


I have just installed two 315w panels each with its own MPPT 100/30 charge controller and a battery temperature sensor. I have pretty good sunlight and the batteries are fully charged. Using Victron Connect, I see that one panel is putting out about 120W, and the other is zero. The panel with zero output shows voltage, but no current. If i put a load on the batteries, both units kick in. My guess is that synchronized charging may shut down one controller if there is excess current? Is this correct? I cannot find an explanation in the user manual.....but mayme i am looking in the wrong place. Tomorrow, I will sail the boat and see what happens when the batteries are put under load and discharged some.

ndavies asked
ndavies commented ·

0 Answers

Generator unable to connect (Easysolar 24/3000 -70)

Hallo !

I have an Easysolar 24/3000 system with 10 kW lithium and 1800 wats of panels that work fine. However I need a backup source of energy to charge my battery in October/November since the sun is low/absent in Norway then....

I have a 2,2 kW generator that works fine for tools, lights etc. if I use it directly -but I can not use it to charge my battery through the multiplus in mye Easysolar (from 2018).

I can see it connect and it shows 100-150 wats of charging for a brief moment before it disconnects.
I have tried to lower input current and I have also hooked off for "Weah AC" in VE.Configure.

The generator is a fairly cheap, but good and very common generator -see picture. I have considered buying a Honda 2.0 i generator -could this generator work better?

(I might only need the generator 2-3 times a year so I want to get away with a small and cheap generator)


Eric Heiberg asked
Eric Heiberg commented ·

1 Answer

BMV-712 not showing the correct state of charge? How can I reset it?

My smart BMV-712 is telling me that my batteries are at 40% and that the time left is just a few hours. The problem is that I know that the battery are fully charged. How can I fix this? I think it should be an adjustment somewhere, but I can't figure out what. Help please. Thanks

Inhabor asked
Tony Alba answered ·

2 Answers


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