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AGM Battery

Charge independently 3 12V series battery

Dear you all,

I am writing to ask help for a purchase.
I own 3 AGM 100A 12V batteries, that I need to connect in series to power a DC 36V motor. I would like to recharge the batteries independently, with 3 different 12V chargers, my to obtain the best single-battery charge. I thought to use a system like the LiPo multiple cells recharger work

Which is the best option to do that? May the bpc121544002 Blue Smart 3x12V outputs charger work? I couldn’t find any useful information.

Is there any other solution? Or is it better to recharge it with a single 36V charger?

My kindest regards,

Luca Gilardi

lgilardi asked
kevgermany answered ·

1 Answer

Are my SLA batteries ruined?

I've had them for almost two years. They are generic alibaba type SLAs. It seems like the capacity is getting really bad, such than the SOC is more than 25% off compared to the rated capacity. I never let them go lower than 60% according to the original SOC calculation. I'm not in an area with a lot of daylight hours currently. They're supposed to be 12v 250AH SLAs, and I have 4 of them in a 24v configuration to be 24v at 500AH. Here are my graphs and charge/BMV settings, as you can see it goes to 24v at like 80% SOC. 100% SOC sync happens when the batteries are getting like 300watts. Midpoint looks okay so shouldn't be a bad cell. Is there anything I can do aside from halving the BMV amp hours?




vulture asked
vulture commented ·

2 Answers

Should I use "high" or "normal" mode on an IP65 for this AGM battery?

I have a similar question to this original post, but with some more details to provide. My 100AH AGM battery is a Fusion CBC12V100AH and includes the following information printed on it regarding constant voltage charging:

Standby Use (Float Charge): 13.5~13.8 Volts @ 25C
Cyclic Use: 14.4~15.0 Volts @ 25C
Max Charging Current: 30A

Based on that information when the battery has been moderately discharged I would have thought that using Blue Smart IP65 Charger it would be appropriate to use "high" mode rather than "normal". What is the recommended mode for that information?

aussiebattler asked
Stefanie answered ·

1 Answer

Poor battery performance? New MPPT 100/20 in cold weather

Update: Thanks to @snoobler, I now understand that you cannot trust the measured voltage of a battery system when it’s under load or being charged. Battery specs pertain to measuring voltage at rest. Once I understood this electricity 101 aspect, per the advice of @snoobler, I began to focus on the state of charge (SOC) data to help me home in on the measured voltage that equates to 50% SOC for my system. Once I home in on that value, I’ll be able to refine my charge controller configuration to avoid defer turning off the load terminals until that voltage is reached.

I installed a new outdoor pole mounted off-grid solar system of the configuration shown below in late November 2021. I am trying to determine if the battery performance I’m experiencing should be expected during colder winter months.

The 200Ah dual 12V AGM deep cycle parallel battery system appears to power the ~1.4A/18W 12VDC total load for only a few hours before the MPPT automatically shuts off the load via a 12V relay. The load is reliably switched off and on based on the Load output settings shown below.

Even in our variable winter temperatures, it seems that the battery system should be able to power the load for more than just a few hours.

My goal is to enable this system to run for at least 2-3 days without solar charging.

Several Notes and Questions

  • Over discharge damage? Prior to configuring the Load output settings as shown below, I had been using the BatteryLife setting. However, with that setting, the MPPT did not appear to shut off the load during low battery voltage situations. Before I made the switch to the Load output settings shown below, I had seen the battery voltage drop to ~11.6V. I hope I didn’t damage the batteries by discharging them to that extent.
  • Depth of discharge: Is 50% the right target for AGM deep cycle batteries? I’ve read conflicting advice. My current load switch low voltage is set to 12.24V or 50% DoD. If 80% DoD is reasonable, then I would adjust this setting to ~11.9V. However, I don’t see how that would dramatically alter the battery performance of the system.
  • Potential battery damage due to charging in cold temperatures? We’ve had several sunny days during which the the outside temperature was in the mid-teens F. A few nights dropping into the low teens. It’s not clear to me if the AGM batteries could have frozen overnight and gotten damaged if attempting to charge them during the day. I do not yet have a battery temperature sensor attached via the SmartShunt, but am considering adding one so that I can configure the MPPT to avoid charging at low temperatures. I am not sure if the charging that has occurred to date during low temperature days. We’ve seen several days in the ~20F or so since I installed the system with lower overnight temperatures.
  • Temperature compensation: It’s not clear to me how I should convert the -4 mV/Cell/C as specified in the battery specs in the diagram below to the F unit that is apparently needed in the MPPT settings.
  • Translating battery spec absorption range: I used 14.4 as the rough midpoint of the battery spec’s 14.1-14.7V absorption number. Does that sound reasonable?
  • Purpose of bulk value in battery spec? How, if at all, should I factor the batter spec’s Bulk number into the MPPT configuration?
  • Load switch high value: I currently set this at 12.5V or roughly 75% SOC. Is this a reasonable setting?
  • Switch to lithium? 100ah? Perhaps 24V? I’d hate to have to switch out these new AGM batteries, but if that’s what’s necessary, then so be it. If that comes to pass, would I be best served by going the lithium route? Since lithium can deal with deeper discharges, I’m wondering if 100ah 12V would suffice. Since most of the system components can support 24VDC (I’d swap out the relay and the 12VDC-USB C 5VDC down converter for 24VDC compatible units), I’m also wondering if I should make the switch to 24VDC battery system.

Recent Day

Mid-30sF day. Data captured via MQTT from the VenusOS-based Raspberry Pi.




The fact that the system is entering bulk charging mode multiple times a day appears to point out a problem with the battery systems. I gather that with a properly sized and well operating battery system, bulk mode shouldn’t be needed more than once per day.


MPPT Settings



Battery Specs


System Overview


ckamps asked
ckamps edited ·

1 Answer

Supercycle battery life used in deep cycle mode

I have 170Ah supercycle batteries in a house bank on a boat. I believe performance is deteriorating after just 15 months use. Can any body share experience of longer life? I was expecting something in the range of 7-10 years as operating life based on other premium AGM deep cycle batteries.

insequent asked
cheyenne7 edited ·

4 Answers

Setting Up Orion TR Smart 12 | 12 - 30A To Charge Aux Battery

I am after some advice/help setting up a Victron Orion TR Smart as a charger for an Auxiliary battery.

-I am using an Orion TR-Smart 12 | 12 - 30A NON-Isolated DC-DC unit.

-It is installed in an older diesel vehicle with a regular alternator, output of alternator is 60A.

-I have a lead acid starting battery that is connected to the Victron Orion Input, and the Output goes to an EnerSys Powersafe SBS-100F 100AH AGM Battery. (Auxiliary/Second Battery)

-There is also a Victron MPPT Solar Regulator connected to the Auxiliary battery.

-My goal is to have the auxiliary battery receiving charge from the DC-DC Unit, which is run off the main battery.

-I will be running a subwoofer, 60LTR fridge/freezer and volt meter off the Auxiliary Battery.

I am not sure what settings I should be using as a base setup (through the VictronConnect app).

Would anyone be able to give me suitable settings for this kind of use?



Kind Regards.


ram13 asked
Matthias Lange - DE answered ·

1 Answer

Victron MPPT 100/30 with FullRiver DC105-12 AGM Battery Bank - Configuration


I am sharing the battery setup information I received from FullRiver Energy.

My setup is as follow:

4 - FullRiver DC105-12 AGM Batteries Connected in Parallel for a total system of 12V / 420Ah.

I am using a VictronSmartShunt in addition to 2 Canadian Solar 250W Solar Panels Connected to Victron MMPT 100/30 charge controllers. Have two of the 100/30 one for each panel.

The configuration I received from FullRiver to configure the battery setting is as follow:

  • Battery Volt: 12V
  • Max charge Current: 105A (you’d have a theoretical max of ~30-40A)
  • Absorption Voltage: 14.7V
  • Float Voltage: 13.6V
  • Equalization Voltage: 14.7V
  • Re-Bulk Voltage offset: 0.6V
  • Absorption Duration: Adaptive
  • Maximum Absorption Time: 4 Hrs
  • Tail Current: 8A
  • Equalization Current Percentage: 100%
  • Automatic Equalization: Disabled
  • Equalization stop mode: Fixed Time (lowest it goes since it’s disabled)
  • Maximum Equalization Duration: Lowest setting it can be
  • Temperature Compensation (mV/°C): -24mV/C
  • Low-Temperature Cutoff (optional): -40C

Hope this helps those of you with this type of setup.

svreverie asked
Alexandra answered ·

1 Answer

Safe to have batteries in cabin?

Hi! On my boat, the batteries are currently mounted in the engine compartment. To get a better weight distribution, I am thinking of moving them forward in the boat. I was thinking of a space between the mid-cabin and the toilet. Is there any risk of having sealed Victron AGM batteries indoor? In a year or two I am planning to install a Victron multiplus in the same compartment. I don't think the multiplus is ignition proof?

andreholgersson asked
harold answered ·

2 Answers

Need advise on a system

I'm replacing the inverter in my tractor with a Multiplus-II and am looking for advise for the best way to go with my current battery banks. The truck came from the factory with 2 battery banks, The "truck" side consists of (4) Lead Acid group 31 batteries. The "house" side has (4) AGM group 31's. I'm sure you see the problem already.... I'm changing out the "truck" bank to AGM's.

They are connected through a solenoid, or combiner, controlled by a battery management system (BMS) that consists of shunts on either battery bank. When I am driving down the road the BMS closes the solenoid and charges both banks through a 300 amp brushless alternator. When I'm parked the system runs off of both banks until the truck side falls to 12.6 volts. At that time the BMS opens the solenoid, disconnecting the truck bank, and continues to run off the house bank until they are depleted. Once depleted the BMS then auto starts the truck, bumps the idle and runs for approximately 1 hour to recharge the batteries as much as possible and the process starts over.

Besides the obvious mixing of battery chemistry that I am resolving by switching out the truck batteries with matching AGM's does anyone see any other issues I may have? The reason for all this is I have frequent issues with the lead acid batteries and my original inverter (Xantrex Freedom HFS 2000) just fried. I'm concerned with the house batteries being depleted far more than the truck batteries, then through either the alternator or the shore power of the inverter, overcharging the truck batteries.

Thinking of:

(4) Group 31 Interstate AGM-7's

Rewire both battery banks to Inverter with 4/0

MultiPlus-II 12/3000/120-50


GX Touch 50

safe-harbor-haulers asked
safe-harbor-haulers answered ·

9 Answers

Quality of leroy Marlin Xunzel agm battery?

Last week I bought an agm solar battery from leroy Marlin.

Name solarix, brand Xunzel.

Is leroy Marlin brand for all solar accessories.

I will use it to support my agm victronenergy, either separately or in parallel as needed.

It has charging and internal resistance characteristics very similar to the victronenergy and this is good for parallel.

In fact, measuring with a schunt the current was divided almost perfectly (in relation to the capacity).

What do you think of these batteries and this brand?

They are medium quality batteries ... Not at the level of agm rolls or troyan, but not bad either.

The price range is about that of victronenergy agm batteries.

The data sheet is very interesting:

It performs worse in cold weather than victronenergy.

It has performances similar to victronenergy in terms of capacity in relation to the C rate, but victronenergy is slightly higher.

But it has performances of duration in cycles and in years much superior to the agm victronenergy.

100% DOD: unknown victronenergy, xunzel 400 cycles.

80% DOD: victronenergy 400 cycles, xunzel 600 cycles.

50% DOD: victronenergy 600 cycles, xunzel 900 cycles

30% DOD: victronenergy 1500 cycles, xunzel 1300 cycles.

10% DOD: unknown victronenergy, xunzel over 2000 cycles.

Standby use at 20 C°: victronenergy 7/10 years, xunzel 10/14 years.

Basically it appears that these xunzel agm have high DOD performance, similar to victron agm supercycle.

Victronenergy deep cycle AGM years or cycle duration is not exceptional for a solar battery at these price.

Here the two datasheets: AOvVaw0AWZwMcTcRp-3RcREF_PXQ

francesco asked
Paul B answered ·

1 Answer

MultiPlus ground wire overheating in an RV

I'm trying to diagnose an issue on a van that was brought into my shop. I'm pretty good on the electrical side but it's not my wheelhouse so I wanted to run this by the group for some super pro thoughts. The issue is the ground from the MultiPlus is overheating and has started to char. System is now shut down till the issue can be resolved.

Specs on the system are: Small home built camper van with 3 AGM batteries and a 2000W Mulitplus has a #14 ground from the Multiplus to the DC fuse box which in turn is run to the negative battery with a #10 wire and then to the chassis with a #2 wire. Positive & Negative from Multi are #2. My guess is that the negative wire from the multi was loose somewhere forcing current to run through the undersized ground wire. Does this sound reasonable or is there something I'm not seeing here?

Also what size should the ground be on this? I feel like #6 at minimum, possibly same size as negative? I'm also going to upgrade this to busbars so all connections are made there instead of on the battery terminals.

Thanks for the help!

Woody asked
Paul B answered ·

1 Answer

Another AGM battery settings question

To correctly configure a BMV-712 and Smart Solar 100/50 with Motomaster Eliminator Ultra batteries I tried to configure the settings as far I understood, but as I am not sure how to deal with the ranges being given I would be happy if somebody could have a look and check.

Shall I go lower end, midrange, upper Limit?

Also, would you cutoff heavy load based on SoC or Voltage (@ what values?)


Manufacturers spec says:

Reserve Capacity 409 minutes

AmpHours (@20 hours) 190

Charge/Absorption/Equalize between 13.8-14.6 @25°C

Float/Standby 13.4-13.6 @25°C

The Peukert’s coefficient for this battery is 1.24.

We do not recommend equalization charging for sealed AGM batteries such as this one.

We would recommend a maximum charging current of 60 amps.



vicky asked
kevgermany answered ·

1 Answer

BMV 702 zeigt falschen Batteriestatus an

Guten Abend Ich habe zur Batterieüberwachung einen Victron BMV 702 black mit Shunt 500A eingebaut. Die Verbraucherbatterie 150ah agm wird via Laderegler MPPT 75/15 über 2 Solarpanel à 130Watt geladen. Der Shunt ist meines Erachtens korrekt angeschlossen, alle Minuspole inkl. der Laderegler MPPT 75/15 sind über den Shunt geschalten. Nun zum Problem. Ca 3 Mte nach der Installation zeigt der Batteriewächter einen kontinuierlichen Verlust in % des Batteriestatus an. Heisst nach dem Reset geht es ca 10h und er zeigt 0% Batterieladung an, auch wenn keine Verbraucher in Betrieb sind und via externes Messgerät die Batterie als voll geladen angezeigt wird. Hat jemand Erfahrung damit? Vielen Dank für die Antworten!

milo-oo7 asked
Stefanie answered ·

4 Answers

How to wire two camper AGM batteries in parallel

We have an Airstream with two 12v AGM batteries in parallel. Presently there are connections to both battery‘s positive and negative terminals- my plan has been to run all the negative connections through the shunt and to one battery‘s negative terminal, then all the positive connections to the opposite battery‘s positive terminal. Is this corrrect?

pgrogan5326 asked
kevgermany answered ·

1 Answer

Victronenergy AGm deep cycle performance and boost voltage

Hello, I have a 110 Ah Victronenergy AGm deep cycle, from April 2021.
-It is managed by a 30 A epever 3210AN mppt charge controller. With a 300 watt panel.
-It is discharged daily on average of 15 / 25AH, which is with DOD 15/25%, which is ún SOC 85/75%.
- has about 260 cycles
- it is recharged to 100% every day (in the Canary Islands the sun is good even in winter) with the parameters of the victronenergy datasheet, boost 14.4v, float 13.8v, temperature coefficient - 24mV / C, boost time 1-3 hours .
- once a month I do a slight equalization at 14.7v 3 hours.
-I collect all data from victronenergy smartshunt and epever module for statistics, in particular I record the open circuit voltage every night after discharge.

I noticed that for the first 2 months the ocv for each SOC rose slightly.
Instead, since November, I have noticed a drop in ocv for each SOC of 0.07v.

For example after a discharge of - 12AH before it had ocv 12.88 / 12.91,
now after a discharge of - 12ah, it has an ocv of 12.82 / 12.85v.
At 100% before it had an ocv 13.20 / 13.25v, now it has an ocv 13.12 / 13.18v.

Instead the capacity remained the same.
Only the ocv dropped by 0.07v.

I did dozens of tests and collected the ocv after 30 minutes of the discharge 270 times, every night.

Do you think this is normal?
Could it be the temperature?
From April to October the battery was discharged at around 26/28 degrees Celsius. 

Then I have another question:
The victronenergy datasheet says: boost 14.2-14.6v.
What does it mean?
I am using 14.4v because I have done various tests with smartshuunt and between 14.4v and 14.6v, the current does not change. So I prefer a not too high boost voltage.

I'm doing well?

The Rolls battery technical service told me that I'm wrong and that I have to recharge with boost at 14.7 v and fixed boost time of 4 hours independent of the DOD. Otherwise my battery will sulfate in less than 12 months.
He also claims that the victronenergy adaptive boost time is not good, because the boost time must always be the same, regardless of the DOD, because it always serves to recharge the last 20%.
But I prefer to follow the victronenergy datasheet.

Could the 0.07v drop in ocv be a sign of sulfation?
(I don't believe because the capacity hasn't changed)

francesco asked
francesco commented ·

0 Answers

Victronenergy Agm deep cycle voltage drop after 7 months
Hello, I repeat a question that I have already asked in a simpler way, because I did not get an answer.

I have a Victronenergy AGm deep cycle 110ah for 7/8 months.
Since November I have noticed a drop in ocv (OPEN CIRCUIT VOLTAGE) of 0.07 / 0.08v for each discharge.

For instance:
Previously with a discharge of - 6ah it had ocv 13.00 / 12.97v,
Now 12.93 / 12.94v.

 before with discharge of - 12ah it had ocv 12.88 / 12.91v
Now it has 12.80 / 12.83v.

Previously with a discharge of - 20ah it had 12.73 / 12.75v ocv.
Now 12.66 / 12.68v.

This decline happened in November. For the first 6 months in the summer, the ocv remained constant.
The battery is recharged every day to 100% with the parameters of the victronenergy datasheet (abs voltage 14.4 / 14.5v, float 13.8v, abs time 1-3 hours, temperature coefficient - 24mV / C °).

The only thing that has changed is the temperature. Before it was on average 27/30 C °.
From November on average it is 20 / 22C °.

For more detailed information on the conditions of use of the battery read here:

Is this voltage drop normal? Is it the temperature? Or is the battery sulfating?


francesco asked
francesco commented ·

2 Answers

Choosing / editing a battery preset for Rolls S12 series

I have 8x 12V Rolls S12 230AGM-RE in two 48V strings charged by 6x300W PV panels via EasySolar 48/5000.

The Victron Connect App factory Preset 2 seems fine except for the Absorb Voltage 14.4/57.6 whereas the Rolls user guide gives 14.7/58.8. (Float is same as the Victron Preset 2)

Should I edit the Preset 2 Absorb Voltage to 58.8 or use the Spiral AGM preset?

Is the higher Absorb setting necessary?

Is the Rolls S12 series a spiral AGM?

Thank you.

hastings asked
francesco answered ·

2 Answers

AGM settings

Hi All.

Sorry for another setting question.
I have just had to replace my second 120ah AGM in 14months and short of getting 2 faulty batteries I need to know why. Both batteries had very little use. last one sat in my shed connected to the controller for 5 months and failed on my first camp 2 weeks ago.

I have a 75/10 set to agm and thought that was all I needed. Left it connected to a small panel thinking I was doing the right thing keeping it topped up.

What am I doing wrong?

Thanks, Darren.

razzle308 asked
kevgermany answered ·

13 Answers

Zeigt die Solarhistory der mppt-App wirklich die min. Spannung der Batterie?


ich habe meine kleine Inselanlage (2x 340W Panel und 4x140Ah Batterien => 24V 280Ah) jetzt seit einigen Tagen in Betrieb.

Mir ist aufgefallen dass in der Solarhistory bei Min.Battery immer ein Wert angezeigt wird der eigentlich bedeuten würde dass die Batterie total entladen ist(laut Datenblatt 12,2V)... auch wenn sie am Tag davor voll aufgeladen war.

Da ich aber fast keine Last dran habe ... evtl. 15W bei 230V Led-Licht für 3h ... kann das eigentlich nicht sein auch wenn das Wetter nicht toll ist...

Daher meine Frage ob das wirklich die Spannung an der Batterie beim start des Ladevorgangs ist, bzw. ob das jemand schon so gesehen hat.

Hier meine Solarhistory seit Start vor 14 Tagen...


Bin Dankbar für jede Info/Hilfe...

richard70 asked
richard70 answered ·

6 Answers

Blue Smart IP22 Charger 12v 30A UK Plug Fuse

Hi - I have a Blue Smart IP22 Charger 12v 30A charger hooked up to 3 95aH AGM batteries in parallel. This has been used on shore power without issue to charge batteries from around 95% to 100% without issue, however when I've used this at home to charge from 85% it seems to have blown the 5amp fuse in the UK plug, has anyone else had issues with this, or can suggest any reasons why it would be blowing this fuse? To me it seems like 5amp for this fuse is small on a 30amp charger but I'm trusting it's right as that's what came from the supplier? Thanks!

kylec-03 asked
idunne answered ·

2 Answers

Battery settings in VictronConnect

Hi folks. My system was set up using 4 12v 200ah batteries. The installer told me that this made the system a 200ah system at 48v.

within the victronconnect app, it displays my aH as 400 - is this wrong? Do I need to change it?

also, dynamic cut off was off. I want to switch it on. Is it best to leave the voltage settings that are there as default?

thank you

magicdesign asked
magicdesign edited ·

1 Answer

Batteries voltage falling rapidly?


I have the following configuration:

  1. Victron Energy Multiplus 12/800/35-16
  2. Two Omnipower OPR120-12, 12V 120Ah Deep Cycle AGM/Gel Hybrid VRLA Batteries (connected in parallel)

I use the system for my desktop and TV set during power outages, they are quite common where I live. I have specced the system to last at least 2 hours as that's usually how long our power outages last. The average power draw for my desktop and Tv set fluctuates from 260W to about 310W. I use the Victron MK3-USB interface on my laptop to monitor the system.

The problem that I have been having is the voltage dips very quickly under this power draw, it typically starts at around 13.5V-13.7V (Float Voltage) and within 20min falls to 11.5V. I have my shut-off setting set for 11.5V but I know the minimum voltage for these batteries is 10.5V. At 11.5V the State of Charge according to the Victron App is still 97%.

The only thing I can think is wrong is one of my settings have to be wrong? I have added screenshots below of all my settings. Any advice will be greatly appreciated.








Thanks again!

ruben40870 asked
ruben40870 commented ·

2 Answers

Information about cyrix-li-ct function

Victron hive mind. I have two questions re: Cyrix-li-ct.

1. Will this device work like the Cyrix-ct if not connected to a BMS?

2. Will this device work with Lynx BMS?

Thanks in advance, R

rupez1 asked

0 Answers

Presets on MPPT 75/15

We have two Lifeline 6v 400 Ah AGM batteries connected in series with a 210 Watt solar panel and a MPPT 75/15 controller. While setting up the controller what presets should I use? There is one for spiral AGM, is there much difference?

clueless asked
kevgermany answered ·

1 Answer

Interested in forum views regards bank configuration.

Actual bank comprising 20x 55ah agm.
Been coming across lot of articles. posts etc regards actual available capacity depending upon how configured.

Had intended to just go 4 in series then combine the 5 strings in parallel.

Other option thinking 10 in parallel x 2 strings series to produce 2 x 24v banks of 10 then combine those. In this setup running across a lot of differing opinion as how to configure. Two straight end to end of 5 in series or 5 x 2 in series connected parallel.

Basically all configurations make sense for differing reasons am leaning towards cross string grouping as apparently provides better charging balance across the entire bank but will hold my hands up and admit just dont know so many conflicting opinions.

jamesinwa asked
seb71 commented ·

2 Answers

MultiPlus 12/1600/70 - DIP setting for AGM batteries

I recently changed to AGM battery and accordingly changed the charging programme using the DIP settings on my MultiPlus 12/1600/70 which I operate together with the multi control unit. Following the instructions I used the device only with the inverter on and unplugged from the shore line. I set DS1 off and DS2 on and toggled DS3 one time. According to the manual this should provide an absorption voltage of 14.7V. However, I never can see this voltage on the batteries which are continuously monitored using a voltmeter provided with the solar panel controller. Without sun - thus only the MultiPlus charger - the max voltage is about 14.2V and then the device goes into float (13.8V). The solar controller (with sun) goes up to 14.75V as set.

Is the setting as provided in the manual correct? Is ON where the DIP says ON? Is the DIP changes not been stored with the Control Unit connected? Thus - do I need to unplug the Control Unit before toggling DIP3 to store the setting? Maybe somebody has an advice.

drmberger asked
drmberger answered ·

3 Answers

5% mid-point voltage deviation in final 10% of charge


I'am using two serial 12V 122Ah AGM batteries to get 24V. I'am measuring the Mid-Point Voltage via a SmartShunt and a Multimeter.

Between the Batteries there is a thirdparty balancer which measures the voltage of each battery and charges the one with less voltage with up to 2A to equalize.

Also the Battery are AGM of the type "China" :)

+ ---[BAT1]---[BAT2]---- -

I'am charging the batteries with a victron IUoU Charger which delivers maximum 15A

Absorption Voltage is set to 29,4V, compensated by 60mV/degrees measured at the surface of BAT1

so far so easy.

Usually Absorbtion starts at a tail current of around 10A and from around 6-8A tail current (approx. 95% SOC) the Mid-Point deviation reaches 4% or more.

Today: at 94%, 4A Tail Current BAT2 got 15,3V out of the 29,6V feed. For testing reason, the balancer has been removed.

The Age of the batteries is 1,5 Years, i never discharge it more than 70%SOC.

What could be the issue here, higher inner resistance of one Battery? is there a way to mitigate that?

Marco Meile asked
Marco Meile answered ·

2 Answers

exide ep800 with 75/15 175w victron settings


Total loss as to what settings to use with my setup. I have;

175w victron solar panel


Exide ep800 agm 95w

I can't find any information on correct settings other than this screenshot. Could someone point me in the right direction for my settings please?


whosthatgirl asked

0 Answers

BSC 24/12 IP67 settings for PAGM145 Flat Plate AGM battery? Only spiral cell AGM in advanced settings.

I have searched and found similar questions but none exactly the same relating to the Blue Smart Charge, I have seen some for the MPPT products, but not the BSC24/12 IP67.

The question is what settings should I apply for a pair of PAGM145-12 (in series so a 24V system)

I can only find the “spiral cell AGM” preset under advanced settings. This would be like for an Optima Yellow Top or similar.

Would it be Ok to use this preset for the Platinum flat plate AGM?

gareth-k asked
gyzko answered ·

1 Answer

Multiplus-II charger settings/battery type for my AGM battery bank

Hi everyone! I have set up a system with a Multiplus-II 24/3000/70-32 connected to a battery bank made out of 32 UPLUS AGM batteries (data sheet below), 75Ah each. I have two Epever MPPT regulators feeding the battery bank with PV power and mains connected but only used when higher demand or low battery pre-alarm is present via the virtual switch.

I want to configure the charger correctly for this setup to get most out of the batteries and not harm them. My typical daily loads are very low, around 200W, but now and then when using tools or equipment up to 5000w for shorter periods of time. In the future I will add a small electric boiler for hot water and a heat pump for heating/AC.

This is the datasheet for the exact batteries I use:


This is my current settings page for the charger:


I would appreciate any reflections of whether my settings are suitable or not. I don't have very much experience configuring these systems.



mrhappy asked
mrhappy edited ·

0 Answers


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