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mppt charging

MPPT 100/20 doesn't charge to the right float voltage

Good afternoon,

I am using MPPT controllers in a streetlight application.

5 units of smart MPPT 20A and 3 units of smart MPPT 10A are used.

4 units of 20/100 mppts and 2 units of 10A mppt seems not working properly anymore. The float voltage doesn't reach the right value.

It happened studently last 10 to 15 days and it has been working properly for more than six months. We changed only the operation mode yesterday from batterylife to Conv. Algo 1. Streetlight mode was always active. The lights are programmed to switch ON for 7h per night.

The float voltage is now approx. 24Vdc for 24V system and 12V for 12V system. We don't have problem with the meteo, it's sunny all the time.

You can find screenshot from the Victron APP for one of the signage, We can see the same phenomena for almost all the site.












We updated and restarted the MPPTs 4 days ago for some of them but no change happened.

Thank you for your help. Fist time I am facing this issue.

julienmathurin asked
julienmathurin answered ·

1 Answer

Charge voltage setting MPPT 450/100 running ESS

Hello, I have been having issues with the voltage settings on the MPPT 450/100 running ESS. Switched from VE Can to VE direct ....



Turned on DVCC to a setting of 47.70V .

However the MPPT shows 48.40 charge voltage but no clue where he gets it from



at the victron connect App the voltage settings are set to 48V


So where does the system get the 48.40V from ?

Carlos Carvalho asked
klim8skeptic commented ·

4 Answers

Mppt 75/15 not charging


Hi just wondering if anyone can help me as im a newbie have a 120w solar panel on caravan wich generates 21.4 volt at the wires going in to in to mppt when disconected measjred with fluke multi meter, battery shows 12.5v however charger says its off and also shows in blue tooth app solar lower than the battery volts,

Could this mppt be faulty?


keith5637 asked
offroadflow commented ·

2 Answers

Multiplus and smartsolar overcharging with engine on

On my narrowboat, I have a multiplus compact with engine driven Alternator with standard regulator (mobiletron vr lc111) to deliver charge to a bank of 4x105Ah leisure lead/acid batteries. This works fine on its own. This was already there when I bought it.

I've installed 450Pw of solar through a victron mppt 150/45 and that works fine in isolation too. (wired into main battery +/-).

I believe both boxes are set to default settings.

The trouble comes when I switch the engine on there is an immediate bad egg smell from the batteries, indicating overcharging and the mppt appears to get very hot. I am assuming too much current is being delivered to the batteries or voltage is too high if that makes any sense!?

I can get by, by switching off the mppt charging through the app whenever I switch on the engine, but that's not optimal.

Is there a way to change settings to force the Alternator charging to back off, when there is enough solar charge current being delivered? I can't find anything in a manual or searching this forum.

Is possible I need to buy a smarter regulator for my Alternator to allow it to work in tandem with the mppt, happy to receive product suggestions.

Will happily provide more info as directed.

Thank you


tony-jackson asked
tony-jackson commented ·

2 Answers

150/100 MPPT all lights blinking and can’t connect via bluetooth

Hey everyone, my install has just reached the point of finally being able to put a charge into my batteries. Charging went well for two days. When I tried to Bluetooth to the MPPT last night the app stalled out and 20%. Looking at the SCC all three lights were flashing. I’ve downloaded the Victron toolkit and see there are two possible reasons, the first indicating that the rotary dial is in position 7, the other being “any error, Bluetooth connecting, rotary position 0”.

I suspect that the latter is the right error code based on the fact that I couldn’t connect to Bluetooth. How does a person get out of this error? My process was to disconnect the panels from the MPPT, then the batteries and reset the app. Seems a little extreme.

cory-gould asked
Alexandra edited ·

1 Answer

Initial setup of victron charge settings for Leoch agm 130 leisure battery


I am finalising a camper van conversion and have the below victron chargers I need to set the preferences for charging a Leoch AGM 130 leisure battery -

Chargers to setup in app:

- Orion DC Tr smart 12/12 30 non isolated

- MPPT 100/20 48v

- blue smart IP65 12/25

I have the MPPT load outputs feeding the van/starter battery and MPPT battery outputs, the Orion and IP65 feeding the leisure battery.

Nothing unusual here except the load outs from the MPPT to keep the van/starter battery topped up.

I am struggling to determine the best preset

to use in the Bluetooth connect app. The AGM leisure battery isn’t spiral cell from what I can make out and I can’t make heads or tails of confirming battery values.




Can anyone give me a steer on what settings to use in the 3 chargers please and especially how to setup the MPPT to top up the starter battery please?

This is the electric setup in the van:




frazthoms asked
southsideph answered ·

2 Answers

MPPT Solar Charger with ESS external control

According to manual the MPPT follows the VE configure charge curve.

In VE configure the max charge is set to 48V.

However this is not happening.


How to have this fixed as the MPPT keeps increasing voltage when using ESS. If I use hub instead of ESS the MPPT behaves as it should.

Carlos Carvalho asked
Carlos Carvalho answered ·

1 Answer

What mppt to get?

Can you please assist on what size mppt controller I should get:

Solar panel specs

2x 120 w in parallel

Pm 120w per panel

Voc 24.2v

Isc 6.46a

Imp 6.07a

Temp coefficient Voc -0.33%/C

Temp coefficient Isc 0.06%/C

Normal operating cell temp -45 to 80C

Battery specs

13v 108ah lifepo4 lithium 1400wh

Float charge 13.6v

johanr asked
Elimac commented ·

1 Answer

MPPT 150/70 Bulk Charge Current Low

We recently installed an MPPT 150/70 with two Victron Quattro 10kw (split phase), eight 320w 24v solar panels (4 pairs), and two 48v PLBR 9.6kw lithium batteries on a houseboat. The charger should be giving us at least 2,000 watts in full sun.

However, after finally getting it all set up and getting some sun, we are having an issue getting the MPPT to charge. As you can see from the screenshot below, we are getting 74.4v from the solar panels. The MPPT is set to position 7 for lithium batteries and has properly switched to bulk charge when they fell below 54v. We still aren't getting any current though. It goes between 0.5A - 1.5A. We checked the breaker between it and the batteries, the MPPT battery settings, and have the relay set to off. At the time of taking these pictures the houseboat was in full sun and the panels look clean. Any other ideas why we aren't getting a current?


GX Touch Status Pic.png

MPPT Battery Settings.jpg

MPPT Load Settings.jpg

MPPT Relay Off.jpg

ssykes asked
ssykes answered ·

2 Answers

Fronius solar inverter or MPPT controller, if 48V wind power controller is already present?

In our system, we have a 48V battery bank, three parallel-connected Victron Multi Plus II 48V, 3000W inverters and a 48V, 3,5 kW wind charge controller. In some previous posts, I have read about problems, if the wind charge controller works in parallel with the Victron MPPT controller, such as switching to false bulk charging. To add 3,5 kW solar power to our system, is it safer to use Fronius solar inverter, if charging via Victron Multi Plus II causes fewer problems?

aare asked

0 Answers

Adapted plans supporting performance optimizers?

Dear Victron-Team,

PV module performance optimiser get more and more meaning in difficult environments, but also in terms of emergency shoutdown for all PV modules.

Since Tigo is supported in the meantime by a series of inverter manufactures (e.g. Fronius, SMA, Solax, Growatt, Omron, Kostal, Sungrow, Schneider Electric, etc.), I would appreciate, if you could consider the support with Victron MPPTs on near term.

Are there already any plans contrary to your statement from 2019?


thomasw-1 asked
shaneyake commented ·

1 Answer

Smart Solar MPPT 100/20 Not Charging after Firmware update to version 1.56

I have been using the MPPT charge controller since July 2020 with no issues and it, in combination with my solar panel have kept my battery bank charged fully with no issues. Then I did a firmware update via the bluetooth to version 1.56 and it has never worked since. I took the controller back to the store on June 12 where I purchased it and they replaced it.

I installed the new one and I connected it to the batteries and PV and when I connected via bluetooth it performed a couple of mandatory updates one of which was to the version 1.56 firmware. This MPPT controller is behaving the same way and will not charge my batteries.

I performed a full test on the connections and inverter and everything is working flawlessly except for the charge controller.

Has anybody else had issues with this firmware, I have screen shots and the log file from the controller and will share if required.

canoman1957 asked
canoman1957 answered ·

8 Answers

Max charge current setting on MPPT

Setting the max charge current on the MPPT,

Thinking of using a 100/50.

Will that be the max the MPPT will output at all given times?

My battery only has a max charge current of 30a. But my solar capacity would exceed 30a. If the battery is charging at 30a, and I have 50a of solar available what happens to the other 20a? Would be to used by the inverter if a load is turned on? Or would it not be available because of the max charge current set on the MPPT.

I assume DVCC would be helpful in this scenario but it is a small system I am trying to do it as minimal as possible.

Would Smart Battery Sense help identify what is going into the battery and what is surplus solar?

Or do I need a GX and have DVCC enabled.

Thanks in advance.

Isaac Shannos asked
Mike Dorsett answered ·

1 Answer

MPPT 100/30 producing 0 watts 0 amps


I set up my solar system a week ago and have not been able to receive any watts or amps from the system.


2, 100 W panels wired in series

100/30 MPPT charge controller, wired to + and - bus bar

2, 200 AH AGM batteries - 1 year old

Victron battery monitor

The battery voltage will drop below 11V and the panels still do not produce any power. I have disconnected the wires and reconnected, checked all the connections, and checked the fuses on each end of the system. Here are some pictures of the current readings.





It also will read the battery voltage at 13.8V on the Smart Solar, but on the battery monitor it reads 10.8V.

kking asked
wkirby answered ·

2 Answers

Problème de puissance de charge MPPT 75/15

J'ai une installation basique sur mon van avec panneau solaire souple igreen 175W + régulateur MPPT 75/15 + batterie auxiliaire VARTA: 80Ah au plomb.

Jusqu'à présent tout semblait bien fonctionner (puissance fournie jusqu'à 80W en mars et avril, suivi en réel avec l'application Victron connect) mais depuis 1 semaine cependant, j'ai un soucis de puissance (de courant de sortie PV plus précisément) et pourtant le soleil est au rendez-vous.

Depuis 1 semaine donc le courant de sortie du panneau était très faible (0,1, 0,2 A) pour une puissance également très faible 1 à 4W. La tension affichée de sortie PV était de l'ordre de 16V (via application VictronConnect). Le régulateur restait en mode bulk et la batterie n'était jamais totalement chargée du fait de la faible puissance.

J'ai fais le test de tension (voltmètre) directement au borne du Panneau (à vide) j'ai bien une tension de 19V/20V.

Je fais le tests de la tension au bornier du régulateur, panneau branché, j'ai une faible tension (16V) correspondant à l'affichage de l'application Victro Connect.

Je fais le tests de tension aux bornes de la batterie 12,8V

Je fais le tests de tension au bornier batterie du régulateur; 12,8V (donc pas de perte entre la batterie et le régulateur).

Ce matin, pire, la tension aux bornes PV est la même que la tension au bornes de la batterie (12,8V), l'application Victron Connect m'indique une erreur de puissance (en effet 0A PV) alors qu'il fait grand soleil.

La led bleue clignote.

Test à vide du panneau de nouveau: toujours OK 19/20V mais dès que je branche le panneau sur le régulateur, je repasse à une tension de 12,8V.

Je ne sais plus quoi tester, est-ce un pb de batterie ? de régulateur MPPT ou de panneau ?

Merci par avance pour votre aide.

jmaugendre asked
Thierry Cortassa (Victron Energy Staff) answered ·

4 Answers

MPPT doesn't keep high output after power sweep

I have an SmartSolar 150/35 MPPT charger connected to 3x 24 370 panels. The charger is connected to a single 25.6V LiFePO4 battery, Which is connected to an victron Phoenix VE.Direct 24/1200 Inverter. I am making screen recordings of the victron connect from both the mppt & inverter. The first week the system performed well.

Now the system is outputting very low power (<120W) in bulk charging but going up to the normal 300-600W every 10 minutes for a bit before going down to <120W again for the next 10 minutes. I assume the algorithm is doing a sweep every 10 minutes. The image shows the PV voltage & yield over 2 hours. It can be clearly seen that the power is good during the sweep but drops of in between.

My question is why it doesn't keep any of the high output it clearly finds during the sweep? Could it be anything with the Load output settings? I made changes in an attempt to protect the battery bms from over discharge and put the restart voltage too high (>28V). I found out a few days later when it first reached the indicated low voltage point (20.5V). I changed it, but only to keep the above mentioned behaviour, I have tried resetting the factory settings and to set it to always on, but it doesn't want go back to normal charging.


2 hour history

martijn15 asked
martijn15 answered ·

1 Answer

MPPT 75/10 Setup optimization (unique use case)

I am using a MPPT 75/10 as a charge controller for a marine application that might be kind of unique.

Essentially I run two 20 watt solar panels to keep either a ten or a fifteen amp hour Lithium ion battery charged. In full sun the two panels will generate between 2.3 and 2.6 amps. I may add a third panel in which case I would guess peak output is somewhere in the mid 3 amp range.

The battery is then used to power a seven inch depth finder which draws roughly 1.2 to 1.4 amps, and I also have a usb charge port that will draw up to 1.2 amps with a phone or other device plugged in and charging.

Generally speaking the battery would be more than enough to get me by on a four to six hour fishing trip and most likely would even be fine over a longer 8 to 12 hour day, but once a year I do an eleven day trip where we do not see electricity once, so the sun is the only way I can keep everything going for the entire 11 days.

Sometimes I have had issues with the system not charging because the margin in voltage between the battery and PV is not greater than 5 volts. Is there anyway around this? Bottom line, if that sun is giving my panels anything, even if its .02 amps, I need that to be going through my system so the depth finder or the usb charger is being offset in usage by the sun as much as possible.

One reason I moved to the MPPT is because the low sun power delivery is so much better than PWM, but, if the system won't turn on, then I am getting no advantage.

So ultimately I wanted to see if there are any other setup options either within the unit itself, or if anyone had any ideas in the physical wiring setup as to how I might maximize the use of this controller for my situation. Bottom line, if that sun is giving anything, I need it, whether to trickle charge the battery, or to hedge reduction on the battery that the depthfinder might be causing.

Here is an example - If I run that depthfinder 8 hours a day, that is 105 amp hours of usage needed over eleven days. Even if that sun is only giving me .4 amps, over eleven days that would reduce my total amp hours of usage needed to 70. So on a trip like this where electricity is non existent, anytime the charger won't start is essentially a lost opportunity to gain more energy for those super grey days where its going to be all battery.

absentx asked
absentx answered ·

5 Answers

Parallel/Serial - Excel V4.0 spreadsheet (Beginner question)

Good morning all,

I'm just starting out on my foray into solar and playing around with the v4 and looking at small systems. I think I'm being daft, but I don't understand the spreadsheet when it comes to parallel and serial strings, I'm only looking at a two panel system to start with but:

Going from one panel to two in parallel doubles the current as expected

Going from one panel to two in serial doubles the voltage and the current (?) Is this unexpected current increase because of how MPPT works as I'd expected voltage only to increase?

I hope I'm not missing something obvious

keiron asked
Vance Mitchell commented ·

0 Answers

100/20 MPPT + 12-12/30 DCDC + Control Box Wiring Diagram

Hey all!

I’ve gotten myself into a little bit of a spaghetti of a mess trying to rely on my memory with everything coming in and out of the control box for my setup...

basically, all wiring and devices are mounted and wired in and out of the control box, making itself and the device easily removable if required because, both my 100ah deep cycle and the control box will be in the wheel well in the back of my Outback.

I’m hoping someone who is kind enough to help me out with putting together a diagram with the appropriate midi holders in place with what I’m trying to achieve here, I’ll be posting up photos shortly also with how far I’ve gotten so far.

Ultimate goal is to have it looking simple but, fully functional with the ability to show customers what’s possible as well as easy access to its fuses if required.

cheers and thanks all!





I’ll note that -

A. Yes I’ll have ventilation added through the box for the MPPT via a Load controlled fan.

B. I haven’t added a Anderson for the Auxiliary Battery as of yet to the box, however - it will be located on the opposite side to the Fridge output

Rick asked
Rick edited ·

0 Answers

solar controller 75/15.. floats below set point

all of a sudden my smart solar controller 75/15 is set to 13.8volts in float setting, but will only float at 13.6 volts, why is this? i see a few ppl having same issue

garddogg asked
pwfarnell answered ·

1 Answer

Using BMV712 SOC to trigger Multiplus DC Input Low Shutdown without GX Device

Hi I'm looking for some help to understand the best way to trigger the DC Input Low Shutdown on my MultiPlus 3000VA from the BMV712.

I am off grid, solar charging Lithium Smart batteries with an MPPT 100/50, and use a small inverter generator to feed the MultiPlus when solar charging is insufficient.

I would like to limit battery discharge to 15% to maximize the life of the lithium smart batteries.

I've tried tuning the DC Input Low Shutdown voltage settings in the MultiPlus but found too much variability in the actual SOC when the DC Input Low Shutdown is triggered. For example, when a relatively short duration, heavy AC load is applied to the MultiPlus, the DC voltage will drop, triggering the DC Input Low Shutdown at a SOC much higher than if a small continuous AC load is being fed by the MultiPlus.

Attempts to use the battery monitor function of the MultiPlus and the corresponding SOC functionality to trigger shutdown did not work because the MultiPlus SOC is not accounting for the MPPT charge current.

Thank you

abegweit asked
jordash184 commented ·

2 Answers

2 x MPPT Controllers - 1 goes onto absorption earlier than the other, HOW TO STOP THIS?

I have two of the same MPPT 75/15 Controllers, one of them goes to absorption mode way before the other, which means I get to my batteries being full at a slower pace.

The settings are both on factory default.

Is there a reason why this is happening and is there a solution to have them both keep running until my batteries are full.

**One controller has 2 panels conected in series

**The other controller has 2 panels connected in parallel

andrew84 asked
pwfarnell answered ·

2 Answers

Mppt and charger

MPPT and charger

Im using an mppt in parallel to an dc charger, the charger is going into standby without the batteries 2 x 220ah are full loaded. Think the charger looks for the voltage only and goes into standby, because the Voltage from the MPPT . Any idea idea how to work around this issue?

in the Victron MPPT I can set stop loading…but for maintains only, can I use this without issues for a longer time, so let working only the charger if I have power available?

MPPT 75/10 setting
Load 14,4V
Float 13,8 V

Charger setting Gel
Load 14,4V
Float 13,2V or 13,8 not sure from the manual…

Gel Batterie 440ah

achim-1 asked
achim-1 edited ·

1 Answer

Max Charge Current setting for SmartSolar 150|70 MPPT ?

I'm having some trouble understanding the "Max Charge Current" setting, for my MPPT. I have 3x LiFePo4 Battleborn 100 A/H Batteries in parallel, for a total of 300 A/H. I saw a post here (From Stefanie) suggesting that the Max Charge Current should be set at 10% to 20% of that total Battery A/H value. If that is the case, then I'll assume that I can set the parameter to anywhere between 30 and 60 Amps - Is this correct? If this is correct, I will also assume that if this setting value is higher than the current my PV panels can deliver, there is nothing to be concerned about (The MPPT will only charge with the max current that the PV panels will provide)? Thanks !

john-fraser asked
john-fraser commented ·

1 Answer

Charging a 12V Lithium battery from a 48V system

As I understand it, an MPPT Controller could be used to charge a 12V Lithium battery bank (250 Ah), from a 48V system: 4 * (12.8v, 200Ah ) in series.

Question: How do I determine the size of the MPPT for this application?

hookem asked
Matthias Lange - DE answered ·

1 Answer

Mppt 150/85 Not Charging

Hello world

I have 3 phase with 3000/48MPII, 400Ah 48v sonnenschein s12/230 Battery Battery Bank. BMV700 and Venus GX installed 4900W panels. everything is updated to the last firmware

The problem is that my mppt often stop or not start charging when the battery is near full around 85% and even when there is a big load its take from the battries then when the SOC really drop and the voltage is around 49 48v its start charging

and when looking to VRM Graphs is its in Bulk with 0W output

in the [normal] days it goes from Bulk to absorbtion but in float is stays for about 5 to 10 mn then back to bulk

i attached some screen shots of my VRM and its in Vrm world

Thank you




redsam asked
redsam edited ·

3 Answers

Can I use a common negative bus in a 4 MPPT & 4 PV installation?

Hi All. I'm going to install my set, having 4 100/30 each one connected only to a single 450W PV, in a 12v installation. This is already discussed in a previous discussion, and this approach is for the shadows managing and also for the cost and redundancy, beeing better 4 than 1 regulator.

I wonder if, in order to save cabling from 4 to 1, and routing and path (it is thin and strechy), I can connect all the PV negatives to a single 1 cable negative in the PV side, with a section 4 times AWG previuosly selected, and way this to reach all the regulators site, where I will spread again each negative to every regulator PV- input

Positive cables will run independiently , 4 .

Can be possible?

Is there any cons, apart from that if I added new panels I must to run new negatives?


combatdiver asked

0 Answers

Controlling the charge power of a MPPT250/100

Hi all,

Looking for many years at these nice blue boxes of Victron and finally having a good reason to buy one or two: two 4,3V European batteries 48V 16S2P LifePO4 batteries from a luxury yacht.

Since I have wired each of my solar panels seperately I am able to make a nice 3x4 configuration that can be connected to the MPPT250/100 that will charge the 48V 8,6kWh battery. BMS will probably be a Batrium.

A Multiplus 2 (FX) will run on mains power and fall back on batteries when the mains are disconnected.

Normally, the Multiplus charges the batteries at will when there is power availabe from the grid.

I, however, want to control the charge of the batteries in order to have a full charge at the end of the day. The stress on the fully charged cells will be for a shorter time before I disconnect the mains to drain the battery till 40%, where the mains is connected back again in the morning.

In this way I can harvest all my solar energy into the batteries and use the solar energy for our household too.

Is there a way to tell the MPPT250/100 or Multiplus at what speed the batteries can be charged?

offgridd asked
offgridd answered ·

2 Answers


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