Keep charger on or of when batteries under small load?

Dear all,

I am wondering:

Regarding what i read and hear the best to do with (in this case) AGM- deep cycle and super cycle batteries is following, in short:

- Always after use charge battery to full and after that, disconnect charger.

- If not used a fully charged battery for a period: After 1 or 2 months charge batteries again for maintenance purposes and to make sure a complete charge cycle is made.

- Do not interrupt charge when charging a fully charged battery, so do not charge batteries if not necessary and when it is not possible to finsih a complete charge cycle.

In my case:

I have a color control connected to a multiplus 12 volt, connected to 2 x 230 Ah in parallel.

The system can be monitored by the gsm module, so i have a constant network connection. Power drain in standby is around 0,2 amps due to data connection etc. When i use remote console, power drain is around 0,3-0,4 amps. So in other words: i am superslowly draining the batteries.


Do i keep the charger on or off when in standby? For my understanding, it is not very healthy to keep a charger always on whe u store batteries, even not when it has storage mode (see above for my understanding)

But in this case i am slowly draining the batteries, so is it better to leave the charger on when i am not on the boat for like 2 weeks?

For what i do now when i leave the boat:

I charge the batteries to 100 percent. I keep the color control online. After 2 weeks, the day before i go to the boat, i turn on the charger remotely.

Is this the best thing to do?

Best regards, Piet

piet-hein-van-asselen asked
Alexandra commented ·

4 Answers

Blue Smart Charger stuck on Bulk Charge for hours

I'm charging my Battleborn LifePO4 using the Lithium-ion preset and it's been stuck on Bulk Charge @ 13.7V for hours now. Is this normal?

manny-martinez asked
Stefanie commented ·

2 Answers

Phoenix IP43 Charger Startup spike tripping circuit breaker


Sometimes when I power on the IP43 Charger (3/50A), it blows the fuse in the shore power pole. When the fuse is reset by someone of the marina, all works properly again. The unit a powering multiple lead/acid batteries.

I have read that someone else noticed a high startup consumption, but not sure he means this.

Do I have a faulty unit? Any suggestions?



alexv asked
alexv commented ·

1 Answer

New multiplus vs multipluc compact vs multiplus

Hello all,

I'm in a bit of a dilemma, and do not know which route to go with an inverter/charger.

I'm now confused in what to get.

Multiplus - classic, has all the nice features

Multiplus compact - going to be discontinued, what does it lack next to the multiplus?

New multiplus - this I'm not sure what features it has, I see it has different ac in/out with connectors, not hard wired inside, does it come in the box with cable? I cannot find any information or video footage of the new multiplus, looks like nobody has installed or reviewed this product...

All the help would be appreciated!

teddysx3 asked
Matthias Lange - DE answered ·

1 Answer

Multiplus Compact 12/2000/80 won't turn on

When I turn on the Multiplus Compact 12/2000/80 (on a sailboat) to invert or charge, I get one very brief flash of the yellow light and then nothing else. Connecting with VE.Bus smart dongle does not show that it's connected to the multiplus. I can connect with the MK3 and VictronConnect and it shows that the multiplus is attached but off, but when I go into Product Info, it just hangs reading configuration.

I tried cutting power to the inverter for 4+ seconds, and replacing the MEGA fuse, but neither seems to affect anything. It has a digital multi control attached, so I tried toggling the dip switches to disable it and just power on with the switch on the unit, but I see the same behavior. I've tested voltage at the inverter and it matches what I'm reading off the distribution point.

Relevant history:

This started yesterday. While running the generator to charge the batteries I decided to turn on the air con, something we've done occasionally in the past. The multiplus immediately faulted and reset. When it turned back on, the digital multi control panel said that was in bulk charging, but the batteries were not receiving any current. After toggling it off it would not turn back on.

We've been using this multiplus for over a year. A couple months ago we upgraded to Lithium batteries. We leave the inverter on 24/7 now, so we're definitely taxing it more. We usually charge from solar, so we've only a once or twice used it to charge from generator since upgrading to lithium (mostly to test that we had it configured right, and we ran the air con then too).

A week or so ago we were pushing the inverter so hard that we burned up the internal MEGA fuse. I presume the 2000w inverter uses a 175A fuse, but I only have 100A spares at the moment, so that's what I replaced it with for now. I tried swapping it out with a fresh one after our incident yesterday, but still no luck.

Any advice? Did I kill my Multiplus?

bkeepers asked
bkeepers edited ·

2 Answers

Trickle charge multiplus 12/3000 wont charge?


I have a brand new multiplus 12/3000

The trickle charge output is connected to a 12 volt 140 ah battery. The voltage is 12,87

When i turn on the multiplus the trickle charge wont charge (i have a smart shunmt connected to the starter battery) and when the multiplus goes into float status also nothing will happen.

When i disconnect the trickle charge cable i measure 4 volts on the trickle charge outpul.

Is this supposed to be? Will trickle charge only charge when reached a certain battery voltage level?

Best regards and thanks in advance!


piet-hein-van-asselen asked

0 Answers

Suitable charger


I'm looking for a suitable charger for 4 110AH batteries (Victron BAT412101084) which are in a 24V group (220AH).
I also have a SmartSolar MPPT 75|15 connected to batteries.
The batteries are located in a boat as service batteries.
From time to time the batteries are also charged by a diesel engine via a battery isolator.

Can anyone recommend a suitable Victron charger?

szwuntex asked
szwuntex answered ·

3 Answers

Generator Warm Up, Charger walk in

Is there a way to gradually increase or limit charge current on a Multiplus / Cerbo GX to allow Generator to warm up ?

Only presenting FULL charging load when it is warm.

Ideally it would be based on a Cerbo GX temperature input.

Any Help would be much appreciated.

Andrew Jefferies asked
Andrew Jefferies answered ·

1 Answer

Do I need a Isolation transformer with a Blue Power Ip22 charger


The sail drive on my boat suffers from electrolytic corrosion. I just have a Blue power IP 22 charger connected. Do I need a isolation transformer?

I was told the charger itself is a transformer and thus isolated as well so I don't need one. However the corrosion is there?

Many thanks for your opinion.


Martin van der Lee asked

0 Answers

ESS Ladeleistung begrenzen

Ich möchte meine vier US2000 Pylontech schonend aufladen (30A reichen) und die Ladeleistung begrenzen.

Aktuell wird je nach SoC mit bis zu 90 Ampere geladen und der Akku ist schon Mittag wieder voll.

Die Einstellung DVCC "Maximum charge current" wird ingnoriert.

Wenn ich die Leistung vom MPPT 250/100 in dem Menü vom Laderegler begrenze funtioniert das allerdings wird dort die komplette Leistung reduziert. Also auch die Überschusseinspeisung entsprechend begrenzt.

Was verwende ich? 3x5 335 Wp Trina, MPPT 250/100, Multiplus II 3000/35 und der Cerbo GX

rossix asked
michaelvausr commented ·

2 Answers

Smart charger not powering On after firmware update

Hi All,

Could anyone help with this issue please?

I've got 2 smart chargers 1p67 24/12 models. I downloaded the Victron Connect app to connect to them to check the settings but the app would not allow me to connect until I did the firmware updates. The chargers had already been powering on and charging batteries and were working ok, I just wanted to check the settings.

So I followed the prompts and updated the firmware for both chargers through bluetooth.

After this now neither charger will power ON. Both are unresponsive, No led's lighting up or anything. The AC supply is checked and OK, I've isolated them form the batteries and the mains power and reconnected but still no good. Looks like the firmware has killed them??



tough asked
mjacobsen commented ·

2 Answers

Charge Controller showing low Voltage



My 100/50 has been working fine for over six months. Recently I noticed through the connect app that the batteries had failed to charge for a few days. Looking at the controller it was not charging even though it was sunny day. The PV voltage was showing at 12.6. I disconnect the solar inputs and measured 19.8 volts coming from the panels. reconnected the input to controller and back working. This has happened twice now and this time controller is saying 6v and I can't get it to charge. Any thoughts?

adobe asked
adobe commented ·

1 Answer

12v 18a DC to DC circuit breaker size

Just need to know what size circuit breaker to install at both ends..... battery being charged and the battery doing the charging via the DC to DC victron 12v 18a charger ? tks

jacksun asked
wkirby commented ·

2 Answers

Danger Reverse Current when using Battery Protect for charging

Hi together,

I have a question concerning using a BatteryProtect (BP) to disconnect the charge source in a Lithium Battery System with VE.bus bms.

In the BP manual Figure 5 illustrates how to connect the BP for charging situation and it states that "uncontrolled reverse current will flow through a Battery Protect if Vout > Vin."

Now I wonder what happens, when the Voltage of the charger (Vin) drops, i.e. Solar charger when there is no sun or any other charging source that is swithched of. Wouldn't then the Voltage of the Battery (Vout) be higher and thus reverse current flow causing danger?

THanks a lot for your comments, I am abit affraid of burning down my RV...

cheers, Daniel

danielk asked
Justin Cook - Bay Marine Supply USA commented ·

6 Answers

Multi 12 1600 70 Only Charger Mode - Red light

I have set my Multi 12 1600 70 to Charge Only (I have another Victron Inverter doing the inverting).

And when I start the generator in order for the charging to begin the Red alarm light is on and stable (part of the three Green/Yellow/Red lights).

Once in a few minutes, there's a certain kind of "tic" noise, then the green light comes on but nothing happens and the Red alarm light keeps on.

Any ideas or checks I can do?

amit-kvint asked
amit-kvint edited ·

0 Answers

connecting Phoenix charger 12/30 to VE.Configure


I have a phoenix charger but i can't find it on my VE.configure i read that i need the first version of the software to find it. however i can't find any product even with VE.configure 3 and my charger is on.

have you an idea of the problem.


versalift asked
jack2006 answered ·

1 Answer

Victron Phoenix 12/50 Resistance values

Hello together,

is it possible to get the values of the Resistors?

my Charger get up to 16,X Volts and like seen on the Picture, there are 3 burned resistors.

i dont know if the resistors are the reason or the impact for the problem so in first step i want to change the burned ones.

Kind regards



visual asked
jack2006 answered ·

1 Answer

Phoenix Smart Charger does not restart after low temperature shutdown

My PSC IP43 charger is setup to stop charging the LiFePO4 battery when temperature drops below 5°C. It uses data from BMV712 via smart network to get battery temp.

The charger did shut down at 4°C as expected. But it does not restart even after heating the battery compartment up to 8°C.

Is this a bug in the charger firmware or did I miss something?


rheinskipper asked
wkirby answered ·

1 Answer

Correct charger and settings for CA/CA battery


I have a 80 AH Yuasa lead acid CA/CA start/stop battery. In Technical Data Sheet recommended Charge Rate is 4A. Can you help me to choose the correct Blue smart charger and correct settings? I'm between Blue smart 12/7 and 12/10. but I dont know witch one is better for me.

And ,can I use default settings of Blue charger or I shoud change charge rate to 4A according producer recomandation?

maru asked
maru commented ·

1 Answer

Phoenix multiplus 12/3000/120 remote ON/OFF

I have a Phoenix Multiplus 12/3000/120. This specific model

is there any way to separately control the charger and inverter for a two signal BMS like on the new models?

thanks for any help.

kylepaulin asked

0 Answers

Which DC-DC charger 18A or 30A

Dear All,

I am new to all this and busy trying to design a simple electric diagram for my camper-van conversion.

I will only be using a 100Ah leisure battery and I was wondering if the DC-DC smart charger 12 / 12 18A would be enough.

I am assuming charging with the 18A would take twice as much time than with the 30A. Correct?
What would be a rough estimation of how much I could charge with say an hour of driving?

Many thanks for your support.

oliver-vt asked
oliver-vt edited ·

1 Answer

120V Smart IP43 Charger?

I would really like to know if the smart IP43 charger is planned to come out in a 120V version.

I have a smartsolar, BMV, and Raspberry Pi on my RV, and I now need to replace the old shore charger. It looks like my only options are the Skylla-IP44, standard Phoenix, Centaur, or the Multiplus. These are all more charger than I need, not to mention I'm not entirely sure they would work on the Pi.


doug-morford asked
bathnm answered ·

3 Answers

BlueSmartCharger IP67 not compensating voltage drop

My IP67 12/25 charger cannot keep a Lithium battery at constant flow/storage voltage. So the battery is permanently discharging and charging again. The problem is varying voltage drop in the chargers wires due to varying DC loads on the boat.

The problem would be solved if the IP67 charger could compensate for voltage drop. Unfortunately sensing battery voltage via bluetooth network seems to be currently out of reach, which is disappointing.

My idea to overcome the problem is adding a feature to raise the chargers output voltage as a function of current. On my installation a voltage compensation of 15mV/A would be necessary. It would be great if Victron could add a user configurable setting for compensating voltage drop in mV per A of output current.

rheinskipper asked

0 Answers

Bat temp OK, charge still limmited...?

Hi folks,

I cant get my battery to charge at more than about 2kW and I cant see why... Obviously missing something?

Small genny, circa 5kW on AC1. AC current limit set to hold that at 19A, circa 4kW, and working. Gen is a recent upgrade, previous unit was smaller.

Putting a 2kW load on results in circa 1.5kW charge whilst running the load, genny a tad over 4kW.

Dynamic limit is off, Weak AC is on - hence the losses I assume.

Bat will not charge above 2kW and typically hovers at 2kW+/- 80W, which looks suspissiously like a limit of some sort.

Easy solar so Multypluss 48/5000/70.

BYD 13,8kW (Temp mainined at 15C min)

Clearly I am missing something and would apriciate somone pointing out what Iam doing wrong or failing to apriciate.




Alistair Warburton asked
Alistair Warburton answered ·

7 Answers

RV converter-charger replacement?


I have a mostly victron system and looking to replace an ancient RV converter-charger with something to match. Current system:

100ah LifePo4 bank A

(+2x 210ah FLA. Golf-cart 12v house bank B)

Victron BMV712 +shunt

Victron Smart 100-15 and 75-15 MPPTs

Victron Smart BLUE ip67 12-25a 120vAC charger.

I use an external plug-in honda eu2kw (1800w rated) inverter-generator most of the winter. I need to replace 50a/hour if possible BUT I would really like to take advantage of my 100a RV alternator when driving!

My old converter supplied DC when the old built-in Onan 4kw generator was running or the RV was plugged into shore 120vac and outputted 12v to the lights and fans (etc) and charged the old AGM with about 3-45a depending. I currently use the Honda for everything as there is almost no sunlight here in the winter.

I'd like to set up a simple 3-or-4 way switch via the positive battery cables (?) (I.e. "A-B-Off" or "A-Both-B-Off" as well as the gc2 FLA will be needed as a backup source until I can afford more LifePo4 to replace. The slight issue is 50a is a bit too much for my 210ah GC2 FLA's. Sorta need two different chargers, unless...?

I've considered a 2nd BLUE Ip67 12-25a and a switch to select bank for charging but that doesn't much solve the alternator while driving charging issue...

What do I want to look at to get 50a an hour into my LifePo4's using 120vac? 50a as that keeps the Honda in eco mode snd nice and quiet for the 1.5-2 hours recharging.


Trina asked
Trina answered ·

2 Answers

Can a Multiplus 12/3000/120 charge a lithium 3S battery at 12.6V?

I can get a good deal on a Lithium-ION 3S battery, so not a lifepo4 battery.

This battery should be charged at 12.6V.

Rated voltage


Max. Continuous Charge Voltage


Can i use my current Multiplus 12/3000/120 to charge this battery?

campinginthevan asked
Matthias Lange - DE answered ·

1 Answer

Charging LiFePO4 with Blue Smart Charger IP67

I am charging a LiFePO4 battery on a boat using a BSC IP67 12/25.

Those lithium batteries like to be kept around 50% SOC when not in use. So I created a charging profile with 13.3V bulk and 13.2V float/storage for maintaining 50-60% SOC while permanently connected to shore power at the dock. A few hours before using the boat off-grid I switch to another profile, which charges the battery up to 100% SOC with 14.4V absorption and 13.4V float/storage.

The problem is that the BSC IP67 does not re-bulk after loading another profile. Removing AC for a while does the trick but power needs to be removed for minutes to successfully reset the charging curve.

What I need is a quick and easy way to re-bulk (restart the charging curve) manually.

rheinskipper asked

0 Answers

IP43 charger manual says it's compatible with the Smart Battery Sense, but the Smart Battery Sense manual says it's not

I recently bought the IP43 Phoenix Charger (because my old Phoenix charger died suddenly). The charger is located near the batteries, but in a different room, so temperature can vary. According to the IP43 manual (p 5, section 4.1) temperature and voltage compensation is optionally available with the Smart Battery Sense. It's also listed as a related product on the website. So I bought the Battery Sense, installed it, created a network. But... no possibility to add my Phoenix Charger. When I did some further reading, I discovered a page about the VE.Smart Networking claiming the IP43 is NOT compatible with this technology ( ).

What is this about? How can I make my IP43 compensate for temp. differences using the Smart Battery sense? Several similar questions were already posted but no answers... Can anyone please help? Thanks!!



vdepoortere asked
frangar edited ·

4 Answers

Charger Phoenix Smart IP43 Charger no Smart Battery Sense function.

Phoenix Smart IP43 Charger no Smart Battery Sense function.

When will the Smart Battery Sense function be added? in the Phoenix Smart IP43 Charger

kris asked
frangar edited ·

4 Answers

Blue Smart IP22 charger trips automatic fuse

My Blue Smart IP22 charger (12 V / 30 A - 3 outputs) sometimes trips the automatic fuse of the shore supply when starting up. The fuse is 10 A , B-curve type. No other equipment than the charger is connected at that moment so the charger must be the cause of this. When the charger does not trip the fuse, it functions normally.
What could be the cause ? Is this a known issue ? Any suggestions for a solution ?

vingerling asked
thorvald answered ·

5 Answers