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MPPT 100/30 showing hauting behaviour when being in absorption mode


I have installed in my campervan a 315W solar panel + victron MPPT 100/30 + AGM battery 190Ah C10. Everything worked properly during nearly a year. It's been a few days that my MPPT is showing a very strange behaviour when being in Absorption mode.

First of all, the voltage is not kept constant during absorption as it should. The received power keep oscillating between 0W and the maximum power that the PV cell can provide. It looks to me that the MPPT cannot find the maximum power point anymore. Eventually the battery started to make a slight bubbling noise.

I lowered the absorption votlage such that the system could go into float mode and still this strange oscillating behaviour shows up.

Below the configurations and some sceenshots of the status;





Could someone help me with this issue? Might it be an MPPT issue, ... ?

Any help woul be very appreciated.


sacha asked
sacha answered ·

4 Answers

12v AGM leisure battery charging from van alternator

Hello, i have a Ford Tansit van converted into a camper and i would like to charge my leisure battery from the alternator. I was thinking of using the Orion-Tr dc to dc charger. Would this be enough, or is this even a good ideea? Or is there another way of doing it.

Thanks alot :)

buryck asked
southsideph answered ·

3 Answers

Is it possible to use shore power as input for a SmartSolar MPPT charge controller to charge 12V AGM battery?

Hi All,

I am designing my electrics for my van. There is already a 230V AC, shore power, network in my van. I would like to add a 12V circuit for off-grid circumstances, for charging laptop, running lights and a fridge. I would like to mainly charge this battery with 200/300W solar power via the SmartSolar MPPT XX/XX charge controller. But I think it would be beneficial to also be able to charge it via shore power if solar power is no option. Would it be possible and safe to charge the 12V battery (AGM Deep Cycle 250Ah) using a laptop charger plugged in my 230V AC network connected to the SmartSolar MPPT XX/XX charge controller? I would add a breaker between my solar panel and SmartSolar controller and solder a plug on my old laptop charger to easily connect it. This way I don't have to buy a separate 230/12V charger.

Thank you for your help and advice!

laurent444 asked
laurent444 answered ·

2 Answers

Mppt charger settings

I’ve got 3 Victron super cycle 12-230 batteries, connected to a victron solar charger (150/60). I use a victron battery monitor, and even when the batteries are at 75%, it’s still in float. I’ve looked, but couldn’t find the right answer for this. What settings should I input for this battery / charger combo? Funny thing, I’ve got the multiplus as well, it works fine right out of the box as a charger ... no setup needed. Anyway - didn’t want to make a setting error, so thought I’d ask. They should have a default for these batteries:)

dylanhale asked
JohnC answered ·

1 Answer

Full charging of AGMs

Hello. I'm asked to use this facility by posting a q.

In a complete 'lecky refit on a 40 y.o. modest sailboat, I'm fitting 3 groups of AGM batteries - start, port domestics, and s'board domestics. These can be linked. All Optima BlueTops, with a RedTop for starting. The new Beta 14 engine has a 75A 'nominal' alternator with fixed, internally-regulated output voltage. This is nominally 14.4V and the AGMs need 14.7V for full recharge.

I've fitted a Victron ArgoFET 100/3, believing that will do the charging biz. for each battery group... but only so far. I plan to fit some PV panels, for use in 'topping up' when the boat is unattended, and I understand I should fit PV controllers which can/will provide the additional higher Float voltage.

Is this right, and what controller(s) should I fit for this purpose?

oldbilbo asked
neoneddy commented ·

2 Answers

AGM charging current selection on Dolphin charger

Hello everybody,

I have 3 x 12V 95Ah AGM's in parallel and plan is to charge the bank with Dolphin charger when connected to shore power.

Which of below modes you'd choose for setup? If I got it right, "Calcium lead" mode would have the right voltages? I'm planning to use one of the posts of charger to connect the starter battery which is a traditional 12v battery so it would need the "Wet & flooded" option but which one you see would be a best option for this combo with 3 AGM and one wet battery?

Cheers, Mikko



mikko-juuti asked
wkirby answered ·

1 Answer

Agm victron 110ah solar charging absorption time

The article say:

"" "full charge is reached when the current decreases to 3–5 percent of the Ah rating. A battery with high

My new victron 110ah, is daily discharged with 15/ 20% DOD(12.6 open circuit voltage).

After various charging tests with different absorption times, these are the results :

absorb 2A at the ond of 1hr of absorbtion at 14.4v. After, the current drop to 0.8/ 1A at the beginning of floating at 13.8v. And after 4hr of floating decrease at 0.4 A.

If I try to extend the absorption time to 3hr (maximum allowed by my mppt controller), the current does not decrease less than 1.5 / 2 A.
In my opinion it means that it is fully charged with 1 hr of absorption, and with 3 hr I am overcharging it by generating only gas.
Other than that, I measured the open circuit voltage after 24 hours of recharging, and it is 13.14v.
Both with 1 hour of absorption, both With 2 hours of absorption, and with 3 hours of absorption.
What should I do?

francesco asked
francesco commented ·

1 Answer

New victron agm battery accurate solar charging parameters
Hello I just bought a victron deep cycle 110 ah agm to replace the old battery after 3 years.
I would like to ask a Victron technician for the correct parameters.
I only use a solar charge with a fully configurable 30A mppt regulator.
Every day the solar energy is more than enuff to charge completely the battery. 
I discharge the battery every night on average about 20 ah.
I would like to know the correct absorption voltage and the correct duration of the absorption for my use (daily discharge of 20 ah).
Currently I have set 14.5v and absorption duration of 120 minutes with temperature compensation of - 4mV / C / cell. Floating 13.7v.
Today for example after the end of the absorption, the battery absorbed 0.8A in floating at 13.7V.
But trying to increase the floating to 14.5v, I saw that it went up to 2.6A. These is strange for me... 
Does that mean it wasn't fully charged? Or is it due to gas generation?
Then disconnecting the solar panel, after an hour the battery was at 13.5v, so it would appear to be fully charged.

The old agm, at the end of absorption, absorbed 0.8a for both 13.7v and 14.5v.
Why these difference on new battery? 
I can see all these parameters on the victronenergy smartshuunt.

francesco asked
francesco commented ·

2 Answers

Victron SmartSolar(150/35) + SmartShunt(500) for FullRiver DC400-6(AGM)


I am reaching out because I really need help configuring the Victron SmartSolar 150/35 and the SmartShunt 500A for my 48V AGM-battery (8 x Fullriver DC400-6).

Since I live in Norway and charging is very limited in the period from November - February this is tricky!

I have a potential for (theoretical) 33,6A solar charge with my six 325W panels (3s2p), but in the mentioned period I rarely see much current (aprox. 4-6A). So if I follow recommendations with 3-4% of C20 (415Ah) for my batteries I will have a problem with SOC calculations in the shunt. As I have understood the shunt will estimate a 100% SOC when 3 conditions are met: Charged voltage, tail current and charged detection time.

In my case the voltage for charging will be high enough to achieve "charged voltage" every day (because of my 6 panels), but the current will in periods be as low or even lower than the tail current setting if 3-4% (C20) is used. I'm afraid this will result in a very inaccurate SOC calculation..

For the Smartshunt I need help configuring the following settings:
- Charged voltage? Here I have seen that 0,8V below float is recommended, while others recommend 0,8V below absorption for Solar - what is correct?

- Discharge floor? For AGM I believe this value should be no lower than 50% based on what I have read - correct?

- Tail current? In my head I would have to set tail to 0,8% - 1% or even lower and adjust this to about 2% or slightly higher as charging gets better from mid February - sounds resonable?

- Charged detection time? For the charged detection time I have read that 8-10 min would give a better calculation than the default 3 min for solar charging with low current - correct?

- Peukert exponent? Here I have no idea what to configure, all my reading suggests different options so please help me.

- Charge efficiency factor? The only thing that is certain is that the standard 95% must be way too high for my system, and maybe 70-80% would be more correct?

- Current threshold? I have no clue what this means and need help

- Time-to-go averaging period? I have no clue what this means and need help

For the Smartsolar I need help with these settings:
- Temperature compensation? my batteries says -4mV per cell, and eight
6V batteries in series would then be -96mV according to my calculations - correct?

- Re-bulk voltage offset? Here I have no idea what to set and need help

- Maximum absorption time? My batteries should not be in absorption for
more than 8 hours, so maybe the default 6 hours is ok?

- Tail current? Here again I have no idea what to set because of the
varying charging conditions. My Fullriver batteries only have info of
the state when absorption changes to float: I = 0.012 - 0.02 x C20.

If I understand this correct the tail current will taper down from 8,3A
(0,02x415) to 4,98A (0,012x415). My main concern for this is that I
rarely see 8A charging in the darkest period of the year.. The default
value set on the SmartSolar is 1,0A, will it be OK to leave it at
default and max the absorption out to the battery max rating at 8 hours?
I will let the SmartSolar use "Adaptive mode" for Absorption.

I am really sorry to bother you guys with all my questions, but I know the knowledge is in this community and I haven't been able to get any reasonable answers from the "experts".

I would highly appreciate it if anyone could help me.

Thanks in advance!

kennethknashaug asked
kennethknashaug commented ·

1 Answer

10Ah AGM equalization MPPT75/15

Hey everyone

For a small off grid project (IR movement sensor and a connected 10W led light) I bought a 120W PV Panel and the MPPT 75/15 Controller. Those are connected with a 4Ah WET Lead Acid or a 10Ah AGM Battery.

Seems overkill I assume :-) But the thing is, the place for the PV panel is far from optimal. Direct sunlight for only 3 hours max.

I did some Tests today and I observe things I do not fully understand.

The Battery (yt12b-bs) I took from my motocycle was not charged since October 2020 and was quite low (11.78V). The Battery says normal charging at 1A, fast charging at 5A. I therefore kept the basic settings of 5A on the controller and started the process.

After a short time the controller switched from Bulk to Absorbtion later to float. After I disconnected the battery and gave it some time I could watch the voltage drop way below 12.7V.

I played with the settings and first of all set a max current of 1A. Now it spent way more time in Bulk state, eventually changed to Absorbtion and later to Float.

Once again disconnecting the Battery I still saw it fall back lower than 12.7V.

I read a bit about the equalisation mode and thought I'd give it a try. The settings on the controller are still at default (16.2V EQ Voltage) I put everything together and watched the controller.

I'm confused as the Voltage sent to the Battery never reached 16.2V It was stuck at the Absorbtion Voltage of 14.4V I then set the Absorption Voltage to 14.6V and saw the Voltage rise to exactly 14.6V (low amperage of 100mA in Eq mode)

My first question is: Am I wrong expecting to see a equalization Voltage to reach the configured 16.2V? Did I get the Idea wrong?

Secondly: The Voltage on Battery was constantly falling until it hit 12.35V where it stays right now.
Do you think this block is still usable? Oder might it be over with this one?

Thanks in advance

Best Regards

mauam asked
mauam answered ·

3 Answers

Which battery preset to use


I just purchased a 75/15 mppt for my solar panels. I am just wondering what the best preset of settings i should use with my twin century C12-105DA agm batteries.



Edwin Petersen asked
Fahad Khan answered ·

2 Answers

Super Cycle Smart Shunt Settings Advice

Hello there,

I have recently purchased a Victron 230Ah Super Cycle AGM battery and hooked it up to a Victron Smart Shunt. I am wondering what settings are best in the app for the shunt. Any advice would be helpful.

From what I have learnt from the Victron advice video:

Battery capacity: This is set correctly to 230Ah

Charged voltage: This should be set to the "float charge" voltage as per the Super Cycle data sheet which is 13.5-13.8V minus 0.2V (for all 12V batteries). So, it should be set to 13.3V - correct?

Discharge floor: 50% is correct for a AGM

Tail current: Is okay to remain at 4%

Charge efficiency factor: Since, I will be discharging this battery mostly to about 80% or so most of the time. As per the mentioned above video should be changed to between 80-85%.

Any other settings seem to be fine to keep as they are.

What do you think? (current settings in pic below)


nightryder7 asked
nightryder7 edited ·

0 Answers

Battery preconfiguration choice


I'm using a 75/15 Smart in VW California 2020 which has 2 Varta AGM batteries (see pic below).

What battery preconfiguration should I select? The default one is "gel Victron deep discharge 2" but I see a "AGM spiral" option. Should I change it?? Many thanks!



cebonvieuxmaxou asked
Stefanie answered ·

1 Answer

Mid-point voltage deviations occasionally when discharging, but not always?

I have 4 12v AGMs wired in parallel/series for 24v bank with their midpoint monitored from my BMV-712. In the past month or so, once or twice a week I get a midpoint voltage alarm when I discharge below 74%.


The batteries are less than a year old and I think I've taken care of them pretty well, never getting them below 60%. It's very weird that the midpoint voltage doesn't deviate /every/ time my bank is discharged, only some times. For example, in that graph the midpoint voltage was totally fine on the deepest discharge on february 12. In addition, I am sampling from one of the two series midpoints, and it is not linked to the other one because I read here that it could be bad if one of the batteries totally fails. Should I try connecting the two midpoints? Or is there anything else that might be causing his behavior? The batteries never get below 45-degrees.

vulture asked
neoneddy answered ·

2 Answers

Best settings - getting confused

I have completed my install of

  • MPPT 100/30 controlling 2 -170 watt panels wired in series
  • BMV-712
  • And 4 Victron 6V/240Ah AGM Deep Cycle BAT406225084

My problem is figuring out the best settings on the MPPT and BVM. In all my reading I am more confused, much less the fact on the MPPT there are two options for the Victron deep discharge and an AMG. Not to mention on the BVM things like Peukert, charge efficiency, ect.

I just spent a lot of money on all of this and want to get the most out of it and the best battery life.

timdoring asked
timdoring answered ·

2 Answers

AGM with Orion Smart TR 12/12 18 charge current and temp compensation

According to the datasheet of the AGM batteries the charging current without temperature compensation must be limited to 0.2C. When charging a 60Ah AGM with the smallest Orion Smart Tr 12/12-18 the chare current will be 18A or even higher at normal temperature. This corresponds with at least 0.3C. The system will be put in a relative small compartment so I expect that during charging the temperature will rise to 30-40 degrees. Because the Orion Smart does not support temperature compensation and adjustable charge current this seems a less optimal combination. Is there a better solution?

My current thougts are to use a MPPT charger and connect a 12-24V DC/DC converter to the PV input. The Smart MPPT has options for temperature compensation with an external sensor and adjustable charge current setting.

campervan asked
yann-berry commented ·

0 Answers

Field Test on PV Romania: Problem ?


This month there is too much problem on the PV field test. As seen on the image Mono, Split, Poly production is reasonable but Perc is total failure.

Because of this problems it is hard to believe Total Solar Yield field is correct or not ?

I think there is a data integration problem .

Maybe resetting it for this time period and starting over can be more helpful.

Monthly Periods can be more sensible

Also if you supply monthly total stats for past months.

This is a good real life study one of a kind hope it continues.

In my opinion. Thnks. Victron.

heraktitus asked

0 Answers

AGM Supercycle temperature compensation settings


I have 2 brand new AGM supercycle controlled by a Tristar TS-60 in diversion mode (Windmill + solar).

I want to set the temperature compensation in the controller, but I didn't find any data in the one page datasheet of the supercycle batteries.

Could you tell me the median temp for no temp modulation (I used usually for flooded or gel 20°C or 25°C) and the Temperature Compensation (default in controller -0.030 volts)

The batteries does not seems to charge easily (very often in bulk, need very strong power to get in absorption and float), but with the same charging power I successfully used for 8 years 2x victron Gel...and I suspect temperature comp. to be badly set for theses new batteries.

Thank you


oliv56 asked
oliv56 edited ·

3 Answers

Battery Protect 12/24 220A - No Settings to support AGM typical low voltage cut-off recommendations?

We need to protect an off-grid solar system that is primarily used to power an 240VAC 80W sewerage system aerobic pump that is supposed to operate 24/7 and at least 4 hours per day in unattended use (private camp-ground). The battery is a Eclipse Power 280AH Deep Cycle AGM. We have purchased a Battery Protect BP220 to provide a low voltage cut-off to inverter however I notice that the highest low voltage cut-off on the BP220 is only 12.0V [Setting 8]. This is way too low in my research which should be 12.5 to 12.8V. When there is poor light or after use at night, we need the battery protect to kill the load until the batteries are charged sufficiently. Am I using the right product? Are there alternate settings?

Cycle Use Initial Charging Current less than 75A.
Voltage 14.4V~15.0V at 25oC (77o F)
Temp. Coefficient -30mV/oC
Standby Use No limit on Initial Charging Current
Voltage 13.5V~13.8V at 25oC (77o F)
Temp. Coefficient -20mV/oC

andrew-heath asked
andrew-heath edited ·

0 Answers

Battery balancer 24v install


Hello I have looked around but cannot quite find the answer. I have a battery balancer to install on my bank its 8 12v 220ah agm in 24v config

My question is how to connect it up to the system. I have looked at the documents and am still some what lost

I assume it connects to plus on one side and negative on the other and then there is a mid point

From what I can see the mid point is a daisy chain along the plus on the 4 batterys

The plus and negative are as that connected to plus and negative no chain down the bank? If some one could help out I may still be sane by new year

ystwyth1 asked
Matthias Lange - DE commented ·

2 Answers

Victron AGM Deep Cycle battery bank not reaching float.

I have two Victron AGM Deep Cycle 60Ah batteries wired in parallel and connected to a SmartSolar 75 | 10 and a SmartShunt.

It all works pretty much ok, apart from the batteries not always reaching float stage.

As suggested in this support forum, the battery profile I am using is "Gel Victron deep discharge(2)" as it matches the voltages indicated by Victron (float: 13.5/13.8).

Some time ago I used the batteries (down to ~90% as indicated by the smartshunt). Then they recharged to 100% over a few (relatively sunny) days and I could see the charge controller happily flashing as float.

If untouched, normally it goes to bulk a few hours after sunrise and then switches to float.

I recently re-used the batteries (down to ~97%). Again, they recharged back to 100%, but the charge controller doesn't reach the float stage.

The batteries are at about 13.5v.

Just, as a note: weather has been terrible lately, so all this time the charge controller is not going into float we've had rain/fog, etc. so there is extremely low light hitting the panel.

Also, in the history, the controller is indicating some daily consumption, but I haven't been using the system in the past few days and there is no loads attached... not sure why this is happening.

Will low light prevent float?

Shall I lower the float voltage, as the preset keeps it at 13.8?

Is just that indicated consumption preventing it all?

These are some stats from today:



History from this week and last week:


Last week, all seems ok here:


Just to add some more variables :-D

Up to a few weeks ago I was using only one battery, and everything was working perfectly (float and all).

This behaviour started when I connected the batteries in parallel. Also, I don't remember seeing any consumption (unless I was actually using the system) with a single battery.

I added the second battery later on. I know it is not ideal, but the batteries are same model, from the same shop, they have about a month-ish usage difference in time (and zero cycles both).

er-minio asked
er-minio edited ·

3 Answers

Victron Energy Deep Cycle AGM 60Ah - First Charge

I bought a Victron Energy AGM Deep Cycle battery, 60Ah, for a small solar set-up.

I received the battery boxed, but there is not manual/leaflet with it.
I wanted to understand what to do about the first charge, and if it is needed?

In the solar system the solar controller is a Victron MPPT 75|10.

I can charge (if needed) the battery at home before installing it in my solar setup. But I only have an automotive charger I can use (CTEK 5.0).

How do I proceed?

Thanks in advance.

er-minio asked
er-minio commented ·

2 Answers

125Ah AGM Super Cycle tail current


I am using a BMV-712 to monitor my 125Ah AGM Super Cycle battery and charging with a BlueSmart IP67 25A charger.

The BMV is telling me that the battery is at 100% when the charger is still in the absorption stage.

My current BMV settings are:

Charged voltage: 13.2V

Tail current: 3%

Charge detection time: 10m

Peukert exponent: 1.14

Charge efficiency factor: 95%

Please can someone tell me if these are correct or what I should change them to. Datasheets and manuals don’t seem to have all the answers.


markcx asked
doug-morford answered ·

2 Answers

blue charger ip67 - No AGM mode

I have bought the Blue charger ip67 model with 25 amp for a 210 ah AGM set from Varta.

There are no AGM setting. Just "normal", "high" and "li-on". I've been using the "normal" but a bit sketchy that it ramps the voltages up to 14.7, where i thought AGM wasn't happy about going over 14.4

Any advice?

kevinped asked
thorvald commented ·

3 Answers

Do I need a larger Centaur charger?

When building my boat we increased the size of the battery bank significantly from the base spec (from 324 Ah to 1,000 Ah) and also upgraded to Victron Super Cycle AGM. The charger was upgraded from a 12/30 to a 12/60. The thinking was that shore power is generally limited in amps but usually there is plenty of time. However it seems that we're having trouble getting the bank fully charged on shore power. Now reviewing the Victron spec sheet I see that not reaching full charge may be caused by undersizing the charger presumably because the second stage is on a 4 hour timer. Any thoughts on this? Should I replace the Centaur 12/60 with a 12/100? If so will shore power typically be adequate to power the charger?

wings45 asked
jwfrary commented ·

2 Answers

Which preset profile should I use for a 12V 22AH AGM Deep Cycle Battery


I am using a BAT212200084 reference which is a 12V 22AH AGM Deep Cycle Battery.

My charge controller is a MPPT 75/10.

I would use a preset profile in VictronConnect but I am not sure which one I could use.

I saw "AGM Spiral Cell" profile with : Absorption voltage at 14,7V, Float Voltage at 13,8V and Equalize voltage at 16,5V.

Would it be ok with this profile ?


Best Regards

averhaeghe asked
Marnix Keesmaat edited ·

1 Answer

Victron Deep Cycle 12V/200Ah max number in parallel


I often use the Victron Deep Cycle AGM 12V 200Ah battery (telecom style batterie BAT412181164) in a 24V battery bank, consisting of 14 batteries. So 2 Batteries in Series, 7 in parallel. I have no problems with it, works since years perfect.

Now I was told that the maximum number of batteries in parallel is 5. Is this is that true and is there a reason for it? There is nothing written on the Victron product page. There is only the brochure to download, but no manual for this battery.

I am a little concerned because I have planned systems with 10 batteries in parallel for the future.

Best regards and thanks for the help.

offshore asked
warwick commented ·

2 Answers

Max Temp compensated charge voltage for Victron deep Cycle AGM Batteries

I have a max charge voltage setting on my charge controller . I have temp compensation set up at -4mv per cell as per the data sheet . Is there a max charge voltage the batteries will take when very cold ? I note the Absorption range is up to 14.6volt or 14.9 volt fast charge , should 14.9v be the highest even at low temperatures of 5 degrees and under ? or does it not matter and I should set at 15.5 v or something ?

Simon Phillips asked
Alexandra commented ·

0 Answers

AGM Super Cycle Four Bank Significant Reduced Capacity

I installed 4 x 145ah Super Cycle AGM's 18 months ago (Still under Warranty). They were marvelous giving us days service before needing charge. Usual discharge to 12 volts.

This week suddenly we have extremely low capacity and using our normal charge methods (Sterling shorepower 40A charger set to AGM) or the boat engine alternator. Absorption charging at 14.6V and 14.4V respectively. The shorepower drops to 13.6V for float.

I only seem to be able to get 50ah storage into batteries (using NASA Marine Clipper BM2 battery monitor) and then the charge current is down to 1 or 2 Amps within 4 hours or so.

Why would this have happened to four new batteries and so suddenly?

Help very much appreciated.

tom-slattery asked
billknny edited ·

3 Answers

Lithium Service bank and AGM starter battery setup


I have a system with 2 service batteries 100A each one starter battery and one battery for the bow thruster.

The system now is charged with a charger that supports 3 separate banks and 2 alternators from the engines. I now want to replace the service batteries with LiFePO4 from Victron, add a solar panel, a battery bank monitor and be able to see all that from the Simrad MFD.

I have concluded that I need these items:

-Victron Smart LifePO4 100A 2x

-Victron Multiplus 2000W charger/inverter

-Victron MPPT solar charger 100/15 (100w solar panel)

-Victron BMV 712 battery bank monitor

-Victron VE Bus BMS

-Victron Battery protect BP-100

-Victron Cerbo GX

I would like to hear your comments about this setup and your suggestions.

My concern is how is the LifePO4 bank be charged by the alternator and at the same time charging the AGM batteries?


spyros-damigos asked
Paul B answered ·

2 Answers

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