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VictronConnect Settings for Lead Acid

I have just purchased a SmartSolar 100/20 for my 250watt panel and 4 Trojan T105 batteries (12 volt system, 400 amp hours).

I find the VictronConnect App a little confusing:

1. The "Charge voltages" settings within "Expert mode" show "Absorption voltage", "Float voltage" and Equalization voltage". Why is there no setting for Bulk voltage?

(My T105s need 14.8v. Surely I don't set the Absorption voltage to 14.8 do I?)

2. I would have thought that one of the pulldowns for "Battery preset" would be Lead Acid..... Instead I see things like AGM Spiral Cell, Gel Victron Long life, PzS Tubular plate traction(1), (2) and (3). Do I have to change the rotary dial to see the lead Acid option pulldown? Or do I have to go into a custom setting/expert mode to set something as common as a Lead Acid battery?

biff asked
bigbadbob76 answered ·

1 Answer

Midpoint deviation rising

Hello Techs,
I have a 24V system, with 2 closed (mainentance free) Lead Acid battery's of 220Ah, charged by a Quattro, CCGX controlled.
Last years my mid point devition stayed around 0,1 - 0,2 %, currently it is rising to 0,4 - 0,5 %, even when the Quattro is in Storage mode.

Do I need to do something already?


harold asked
harold commented ·

2 Answers

IP22 Charger Boiling Batteries


I have an IP22 3 Output 15 amp charger fitted to my cargo trailer. The trailer is fitted with three 70ah deep cycle batteries connected in parallel. After using the batteries the charger starts to charge at 15 amps during the bulk charge phase. During this stage the batteries start to boil, the batteries does not heat up but I can hear the bubbling when I put my ear close to the batteries. It sounds exactly like when you put you ear to a can of soda after opening it.

From what I have managed to research about lead acid batteries they should be able to charge at 0.3C, seeing that the batteries are 70ah they should be able to safely charge at a current of up to 21 amps. From what I understand the charger also outputs 15 amp which is then equally split between the three outputs, so that means that the batteries should not be able to be charged at more than 5 amps. I have never had this with my Ctek charger which also charged at 5 amps.

Is this normal or should the batteries not be doing this at all? I know the flooded batteries tend to form small bubbles during charing, but this sounds a bit extreme to be just normal gassing.

Below is a diagram of how my system is wired.


I have also attached a screenshot of the settings I currently use to prevent the boiling of the batteries.


Any help or feedback would be appreciated.

Kind regards

Charl Jooste

charlj941 asked
kevgermany answered ·

1 Answer

Recommendations for Battery Upgrade - Lead Acid to Gel

Hi, hope you are all well? I am looking for someone to point me in the right direction of how to approach and where to find some upgraded batteries for my off-grid system please.

I have a BlueSolar MPPT 150v / 70A, Quattro 48i/10000/140 inverter and 20 batteries that I'm told provide 11.98 amp hours at 48v. Also have a CCGX that I use for (basic) remote access.

At present there aren't any issues with the batteries and they seem to keep their charge as well as they have ever done, but they have been in a few years and when I bought this place I knew they would need replacing sometime.

Any help and advice on which batteries to get and where to get them please? I don't have a limitless budget but don't want to do it on a shoestring as I want them to last.

Also, would there be a need to amend / upgrade any of the existing kit if and when the batteries were replaced?

Someone who works on a large hydro project suggested to me that gel rather than lead-acid would be the way forwards.

Any help, advice or general shoving in the right direction would be much appreciated.

Please note though, I inherited this system and I far from a novice let alone an expert, so it will have to be in words of two or less syllables if I am going to grasp it!

Very much appreciated.

Paul (UK)

paul-f asked
seb71 answered ·

2 Answers

input 12 v lead acid starter battery output 24 v electric motor lithium battery

Looking for a dc to dc charger to charge my 280 ah 24 v / 6800wh lifepo4 electric trolling motor drive battery from my 200 ah 12 v starter battery. (50 Amp 12V alternator on main engine)

Can you give me an advice what kind of dc to dc charger would suit my needs ?

something like a orion tr smart 12/24-15a (360w) isolated dc-dc charger should work ?

mikewh asked
justmurph commented ·

4 Answers

Battery is charging - Display shows discharge

I am using a 3 Phase System with a MppT + Smart Shunt + Color Display .

Problem is: Display shows Discharge on Battery, see Pic1, although the only POSSIBLE way for the currrent to go is to charge the Battery. The LEAD Battery is charging per acid reading.

With the settings of the Battery i know for sure that they might be incorrect - standadized settings.

The smart Shunt is polarized correctly - MINUS to System to GND System with 3 Phase System; Minus to Battery to Minus Pole directly on one Pole.

With this setup I already had a correct Current/Charge Reading once; I did however take too much out of battery (battery acid reading showed enough SOC but Display had a lower percentage saved for safety meassures - so battery was in fact still ok to be used - Display did not activate Grid support as it should have - it now does) and the polarization inverted on its own. It went from low percentage to suddenly 100% with negative currentpolarization.

Another issue I face/question I have is that with disconnected Grid and disconnected Load, the only apparent path for the current to take is to charge the Battery. However as you can see in pic 2 the battery still shows a discharge, the Mppt shows correctly positive 5A and positive voltage ( instead of -1A what Color Display shows). Also there are roughly 600W missing in the System ( PV brought a constant of 700W so there is no fluctuation there either.

To summarize my two issues are: Why does my battery charge but is displayed as discharge when Polarization to Battery should be correct

Why am I missing several Hundreds Watts in Display and why does MPPT show a different Current than Color Grid.

All Loadcomponents from System are hooked up on 3Phase system. Nothing else is hooked up inbetween so I am not sending Watts elsewhere undocumented.

Please Help



vicvic123 asked
vicvic123 edited ·

0 Answers

Charging setup for flooded lead acid batteries using the Orion tr smart charger

I have installed an Orion Tr Smart, 12 12 - 30, DC to Dc charger in my travel trailer. It is charging two 225 ah 6v lead acid flooded “golf cart” batteries wired in series to make a 12 v battery bank. I would like to set up the charging profile for these batteries on the Orion charger, but I see that there is no preset for the battery bank that I have.

can anyone suggest a preset or a manual set up for my batteries?

andrew-heys asked
randy-putnam answered ·

1 Answer

PV throttles after meter added

Good morning!

I've got a client where they have a multiplus 3kva, 2x mppt chargers, lead batteries..

The installation is done in such a way that non essentials are split before the inverter, essentials then go through the inverter and then to it's 'backup db'.

The system was setup up that the dc chargers feed back excess pv, essentially supplying upstream to the non essentials, there was no grid meter so if non essentials was not enough it would actually start feeding back to the grid.

When the client contacted me they wanted to upgrade but have no consumption data as there was no grid meter so non essentials wasn't monitored. I recommended we install a grid meter to get total consumption data and work from there. But now the system stopped feeding back the pv. The pv only keeps the batteries charged, then the non essentials gets fed from the grid and pv gets throttled, this is obviously not right as it should feed the essentials and excess should then feed upstream to the non essentials. The system is set up with ess and batteries to discharge to 90%, then kept for backup. Option to feed excess dc pv to grid is checked and dvcc is on and svs is on. Please assist if someone knows what the issue could be? Attached is a screenshot of where the pv was supplying total essential loads, and since the grid meter was installed it dropped pv yield to only charge batteries. Also an image with summary of current installation.



francois asked

0 Answers

MPPT 100V/15A - Safe setup to set and forget?

Hi all!

I recently bought a Victron MPPT controller and I installed it yesterday at a remote location that gets attened once a month.

I have fed it with two 300W panels in series giving me 80V@10A (Overkill I know but those are the panels available to me)

I have installed 10A circuit breakers on both the Positive and Negative before the PV feeds into the Controller. Cable for the PV is 4mm2

I have the Controller charging two identical lead acid truck batteries in series - their capacity would be 300 to 400AH combined. Setting is at 24V. Cable for the charge cable is 10mm2

Using bluetooth I set the charging algorithim to the "Default 2" setting at the advice of an off the grid electrician.

Can you guys give me advice as to how safe this setup is? I am primarily worried about the Charging Algorithim as the descriptions didn't seem to fit exactly with my battery hardware.

Thank you!

offgridclays asked
offgridclays edited ·

1 Answer

electrolyte quality

Hi readers,

After 9 years, I am not sure my electrolyte is up to norm. To measure it, I intend to a) equalize, b) reach full SOC and end of absorption, c) cut off every load and charge, d) wait at least 2 hours and e) read my electrolyte density.

The difference with the "normal" density should allow me to top up as needed (water or acid).

Any other bright idea?

Lionel SEYDOUX asked
Lionel SEYDOUX answered ·

2 Answers

Lithium/Lead Acid battery bank

Hi, I have a narrowboat with 4 x 110ah lead acid batteries monitored by a BMV 702 and connected to a MPPT 100/50 Victron controller and a Multiplus 12/3000/120 Charger/Inverter.

I am looking to optimise the performance and life of the batteries and came across the combination of Lead Acid and Lithium Batteries in parallel which appear to complement their charactistics for optimum performance and Lead Acid battery life.

It appears that the recharge for the batteries is where this system falls down. Am I correct?

If this is the case, has anyone tried to separate the batteries during charging then reconnect for discharge? Would this overcome the problems in charging?

Your advice gratefully recieved


mr-frankie asked
mr-frankie commented ·

1 Answer

Battery Voltage drops when there is no PV power/voltage/Current

The battery voltage drops when there is no available PV power.

Is the battery already faulty/defective?

Battery is a lead-acid AGM.


harry-chavez asked
Guy Stewart (Victron Community Manager) answered ·

1 Answer

Battery voltage drop when high load is connected


I have installed the following off-grid system, which has been working pretty good for one year.

  • 4 300W solar panels
  • SMARTSOLAR MPPT 150/35 48V
  • 8 Acid Lead batteries of 6V each (Deka GC15)

However I'm wondering if the behavior I see when I plug a 1200W water heater during the central hours of the day is expected.

As you can see from following graphs the battery voltage drops when load is active and jumps back to an higher value afterwards.

Reading other posts on this subject I've got this is expected indeed, but my question is: do I have to worry about this voltage drop? In other words: should I power on the AC generator if the battery voltage goes down to 46V like in the picture below?

Thanks a lot,




the-salmon asked
the-salmon commented ·

2 Answers

Cant sync batteries and soc not accurate pls help

Hi i have a set up that consist of this

quattro 15kva

2x smartsola mppt 150/100


Lynx shunt and lynx distributor

Old 800ah lead acid battery 48v (16pcs 12v 200ah)

Can someone help me? I will be replacing the lead acid batteries with pylontech, but for now i have to use the lead acid batteries while waiting for the pylontech. Cant seem to get accurate soc and sync batteries

running on ESS, battery monitor is lynx shunt

gabo asked
hummingbear commented ·

0 Answers

Victron lead carbon operating temperature

Dear All,

There are big differences regarding the operating and charging temperature of lead carbon batteries across different manufacturers. I couldn't find any info on the ones sold by Victron.

Can someone tell me how is the typical cycle count in relation to the temperature? What should be the highest operating temp for these batteries?



eliott asked
eliott edited ·

0 Answers

How harmful is short/transitional overcharging for lead-carbon battery?

I noted that my MPPT charger is rather sluggish to cut solar power down when the sun suddenly comes out of another cloud and so the power input sharply goes up. This causes the voltage to temporarily (5–10 seconds) reach about 15.0–15.5 V (which results in gassing) where the configured maximum is 14.3 V.

I know that overcharging / gassing is harmful, especially that the batteries are sealed (although they are lead-carbon with pretty good spec — 4000 cycles at DOD 50%).

But how harmful are those short/transitional instances of overcharging? Should I be worried to the extent to start searching for a better / more agile charger that will hold maximum configured voltage firmly no matter how quick/high the input power jumps?

greendrake asked
greendrake edited ·

0 Answers

Best setting for lead battery (Varta car battery) and MPPT 100/30


While saving for a good agm battery, I am testing with a Varta car battery, but I am not sure which setting to choose to charge it via the 8 position rotary switch.

At the moment I am in position 2, default setting, but every day in less than an hour it is fully charged, I am using a 375w panel.

Best regards

tosteitor asked
nico934 answered ·

3 Answers

Multiple charge profiles in single smart device?

I was looking at the ip22 3 output charger as a potential solution for my need to charge both a standard lead acid starter battery and a lithium auxiliary battery but have read in other posts that it follows the same charge profile on all outputs. Is there a Victron Smart device that can deal with two battery types in a single unit or should I just get 2 independent chargers?

rich21044 asked
Paul B answered ·

1 Answer

multiplus 12/2000/80 ac power dropouts

I have a MultiPlus 12/2000/80 with VE bus multi control which indiscriminately drops out the AC shore power. Output at the power bollard appears to be normal and nearby boats have no problems. Obviously when it decides to return the power it goes through a new charge cycle. How can I stop these dropouts.



brad-mulholland asked
brad-mulholland answered ·

2 Answers

Orion and Sealed lead batteries

Hi everyone.

I have connected my Orion 12/12 30a to my car/fridge setup and was wondering if anyone can give me some tips for the setup of the battery in the settings menu.

Battery is a Supersafe SBS190F sealed lead battery. Do I select the AGM Algorithm?

And should I adjust the float and absorbtion rate ect?
sorry I am new to all this and really don’t want to cook my batteries.

thanks in advance





caspa24 asked
Matthias Lange - DE commented ·

2 Answers

DC DC charger settings Deep Cycle Lead Acid

I have just installed an Orion-Tr Smart 12|12 - 30 Isolated DC/DC charger to my Mercedes Sprinter van to charge a West Marine Lead Acid 105 Deep Cycle 'House' battery when underway. I was surprised there was no charge profile available for this device/battery match in Victron Connect.

The Merc has a 270Amp Alternator and my house battery spec is:

105 Amp

20 Ah Cap

MCA @ 32°F = 800

185 RC

Can anyone advise me on a charge profile?

Ted Thornton asked
Alexandra answered ·

1 Answer

MPPT 75/15 Multiple Battery Types

I am installing a Smart Solar MPPT 75/15 on my boat, and will wire it to an AGM battery (Deka 8A4D). My engine starting battery (lead acid Deka 904D). The AGM will power the house loads and the starter battery starts the engine - they have separate positive cable runs. However, when my engine is on or when I am connected to shore power, I combine the positive cable runs so both batteries will charge from the engine or shore. This also means that the Smart Solar charger will now be charging both batteries. Are there settings on the MPPT that will work for this scenario? What are the drawbacks? Or should I not do this at all? (I suppose one work around would be turning off the charge controller when the engine is on, but that's not ideal.)

kyleolmstead asked
spirou commented ·

1 Answer

Cyrix-Li-ct with lead acid house battery

Hi, Just wondering if it is possible or advisable to use the lithium version of the cyrix-ct with a SLA house battery.

Im considering this because adding a lithium house battery soon. I understand I would need to control the BMS wire of the relay to enable the relay to close.

Looks like the enable / disable voltage would work with lead acid being 13.4-13.2v

Thanks, Mike

nzmikec asked
nzmikec answered ·

3 Answers

Overload L1 on VE bus system

I often have that alarm cleared about 30s later. Last time yesterday at 18:47, maybe at the starting time of my washing machine, but not sure. Does not alarm me but I woul like to understand! My setup:

- Off grid, 2kWp on my roof + 23kWh lead batteries.

- 2 solar MPPT 150/65, 1 multiplus 24/5000/230

- BMV712, CCGX

Around the time of alert, exact time to be checked I am normally on my local sun time (UT+28m) but VRM may have some other tim:

  • 17:39: -0.40
  • 17:48: -121.00
  • 18:06 -7.07
  • 18:24 -24.90
  • 18:33 -5.90
  • 18:51 -3.60
  • 19:10 -6.7
  • 19:19 -124.60
  • 19:37 -128.00
  • 19:55 -8.10

Any idea?

Lionel SEYDOUX asked
ejrossouw commented ·

3 Answers

Are my MultiPlus II VE Config charger settings correct for 4 x Omnipower 200Ah batteries?

Just want confirmation on my settings. Help will be appreciated. The ones in bold I'm most worried about.

Stop after excessive bulk checked

Lithium batteries unchecked

Storage mode checked

Use equalization (tubular plate traction battery curve) unchecked

Charge curve Adaptive + BatterySafe

Absorption voltage 57.60 V

Float voltage 54.60 V

Charge current 35 A

Repeated absorption time 1.00 Hr

Repeated absorption interval 7.00 Days

Maximum absorption time 8 Hr

Temperature compensation -72.0 mV/deg

Battery Specsheet: Omnipower-240.pdf

The system is a MultiPlus II 48/3000/35-32 with 4 x OmniPower 240AH batteries as a backup system. I'm using the BMV700 as a battery monitor. Venus GX.

jond asked

0 Answers

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

Charging AGM and lead acid battery simultaneous with Victron Centaur 12/60

I recently bought a preowned boat and i noticed that the charger Centaur charger is connected to AGM consumer battery bank and also the lead acid start battery. Jumper setiting on charger is set to AGM.

Can the AGM charge mode damage the lead acid battery in any way? I just had to replace the start battery (4 years old) as it would not recieve chargning any more and i am wondering if the charger can have anything to do with the short life span.

mr-t asked
neoneddy answered ·

1 Answer

How to determine the time it will take to charge a battery with an MPPT or PWM charge controller


I am developing a solar battery system to power actuators in remote areas.

I have investigated both MPPT (SmartSolar) and PWM (BlueSolar) charge controllers for this application. I have a few questions concerning exactly how these work and what settings are possible. My objective is to determine how long it will take to charge my chosen batteries with my chosen solar panels.

It is my understanding that the most common effective method for recharging lead acid batteries is to use 3 phases – bulk, absorption and float. In the bulk phase, the maximum amount of current available from the panels is supplied to the batteries. In the absorption phase, a constant voltage is maintained whilst the current is progressively stepped down. Finally, in the float phase, a small current is supplied at a constant voltage to overcome self-discharge. An MPPT charge controller uses a DC-DC converter to match the batteries voltage during the bulk phase, increasing the current to ensure all the power available from the panels is supplied to the batteries. It then uses pulse width modulation to step down the current progressively during the absorption phase. A PWM charge controller supplies the maximum current from the panels during the bulk phase and, like the MPPT charge controller, uses pulse width modulation during the absorption phase. The charge controller switches from the bulk phase to the absorption phase at ~80% fully charged and sets a timer for the absorption phase based on the initial voltage of the battery before charging began. Is this explanation correct?

For lithium ion batteries, it is my understanding that the absorption phase is not required and that they can be charged entirely within the bulk phase with charging ceasing at a set voltage limit. Is this correct?

Finally, in direct reference to the SmartSolar and BlueSolar products, can an output current limit be set? This may be useful in a situation where the recommended charging current of a battery is less than the output current from the solar panel.

Thank you in advance for your advice

ahayes asked
JohnC commented ·

1 Answer

Replacing Lead Acid service battery with Lithium on a boat.

Hi all,

I am currently running on two 100Ah lead acid batteries on my boat. One is solely used for starting the engine and the other one is the "service" battery for all other loads on board. A blue power charger 12V/30A/3 outputs is used to charge both batteries when the boat is connected to shore power. I also have a automatic charging relay to combine batteries during charging, isolate them when discharging and when starting engines. Basically it looks like this:


On top of that I have a SmartSolar MPPT 100/20 charge controller to charge the service battery from a 200W solar array.

I am now looking into replacing the service lead battery with a Lithium battery of the same or double Ah. If I'm not mistaken, the SmartSolar MPPT controller will be able to charge the Lithium battery but I am not sure about the blue power charger. There are multiple scenarios that I'm not sure about:

1. Charging from the engine only (ex. during night time when the solar panel doesn't work).

2. Charging from the engine and the solar panel (ex. when the boat is running during day time).

3. Charging from the solar panel only (ex. when the engine is not running during day time).

4. Charging from the shore power only (ex. when docked during night time).

5. Charging from the shore power and the solar panel (ex. when docked during day time).

Can anyone enlighten me on how I can properly charge both batteries under all possible scenarios?

Thank you in advance,


nicholas-gouloussis asked
ejrossouw commented ·

1 Answer

Off-grid installation used only during the weekend: best MPPT weekdays configuration


I recently installed the following off-grid system in a country house that will be used only during the weekends:

  • 4 300W solar panels
  • SMARTSOLAR MPPT 150/35 48V
  • 8 Acid Lead batteries of 6V each

Normally I switch on the MP II only when I'm onsite and I need power (once a week so far), during the other days I leave the MP II off. The solar panels and the MPPT are always active (see the screenshot below taken from VEConnect).

I see from the App that every day of the week, even if the MP II is OFF, the batteries are exposed to a charging cycle (bulk, absorption, float). The voltage is raised from 51V to 59V everyday.

That is the behavior suggested from my Victron and battery re-seller.

I'd like to have the confirmation from you that my settings are the best ones in order extend the life of my batteries as much as possible.

Is the daily charging cycle really needed? Wouldn't be better to disconnect the 4 panels during the weekdays and to connect them to the MPPT only during the weekend?

Thanks for your suggestions!


the-salmon asked
Mark answered ·

2 Answers

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