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Battery Protect

Connecting a charger to Load (Out) side of a BatteryProtect


I have two questions:

  1. is a BatteryProtect able to handle reverse current when connected as shown below in case of the BP220? Reverse current would be up to 30A while charging, and Vout >Vin.
  2. In case 1. is possible, let's now now assume the BP220 disconnects due to cell under voltage ( and thus BMS Load Disconnect output being set free floating). When connecting the charger (14.2 or 14.4V) thereafter, what would the voltage drop between Vout and Vin be? Can the BP220 handle 30A reverse current in that case, up to the point when it connects again after 30sec?

Note: the design intent of the layout below is to protect the SmartLithium battery from standby current drawn by the charger in case of cell under voltage. With the original design from the manual, this could only be achieved by a main switch (or pulling the fuse) between battery+ and BP. I cannot use a Cyrix-Li-Charge because my charger applies a IU1oU2oU3 charging characteristic with U3 being below the Cyrix-Li-Charge 13.7V engagement level.


Image: BatteryProtect Manual figure 5, modified (second BP out connected to 1st BP out instead of 1st BP in as in original diagram).



stefancs asked
Matthias Lange - DE commented ·

14 Answers

MPPT 100/15 / 12V 90Ah Gel Batterie / BatteryProtect BP-65 / Orion 12/24-10


ich möchte die Ladestation meines Rasenroboters(29,4V - 240W) durch meinen MPPT / 12V Batterie laden. MPPT und Batterie sind bereits vorhanden, der Rest noch nicht. Die Spannungswandlung von 12V auf 29,4V könnte ich mit dem Orion 12/24-10 vornehmen. Wegen der 20A Laststrom kann ich den Orion aber nicht an den Lastausgang des MPPT (max. 15A) anschließen, sondern muss diesen direkt an die Batterie hängen. Kann ich den BatteryProtect BP-65 benutzen, um die Batterie vor Entladung zu schützen? Der BatteryProtect wäre dann zwischen Batterie und Orion, und durch den Lastausgang des MPPT an Remote gesteuert, analog zu der folgenden Abbildung:


Der Orion wäre hier das "DC loads" im Bild, an dessen Ausgang dann die Roboter Ladestation hängt. (Kann man eigentlich den MPPT Load+ direkt mit dem BP Remote H verbinden, ohne Widerstand?)

Nun darf es beim BP keinen Rückstrom geben, die Frage wäre also, ob es von der Roboter Batterie ausgehend einen Rückstrom über den Orion an den BP geben kann, oder ob der Orion bereits einen Rückstrom verhindert?

Alternative wäre sonst der Orion 12/24-20, der über einen Remote Eingang verfügt, und damit kein BP notwendig wäre. Hier könnte ich dann den Orion Remote+ direkt mit MPPT Load+ verbinden, oder?

Was wäre hier die Empfehlung?

Viele Grüße,


alexander-irion asked
alexander-irion commented ·

4 Answers

Battery Protect Amp Ratings

Is the BP220 rated for 220 Amps at 12 volts and thus 440 amps at 24 volts? Or is it 220Amps at 12 or 24 volts.

Just making sure... ;-)

Patrick asked
Alexandra answered ·

1 Answer

MPPT Completes Bulk and Absorption with Zero Charge Current. Is this normal?

Hi my MPPT went through bulk and absorption cycles today while disconnected from the batteries. I am trying to determine if this is normal behaviour. I would have thought that once the batteries were reconnected bulk charging would resume.

System set up

  • Two 12.8V lithium smart in series feeding 24/3000 Multi-plus operating off grid
  • 1.2kW solar PV fed through a 100/50 MPPT
  • Battery protect between the MPPT and the batteries
  • VE Bus BMS charge disconnect wired to battery protect to prevent charging due to high cell voltage or low temperature.
  • Raspberry PI using Venus SW is logging data to the VRM.

Temperature dropped to -2C overnight for the first time but warmed up to a high of +14C by 2pm

The site is 200+ km away but looking at the VRM data, I noticed the MPPT battery current remained zero throughout the morning presumably due to low temperature shutdown.

I have the MPPT absorption voltage = 28.4V and fixed absorption period of 15min.

You can see in the chart that the MPPT battery voltage reached 28.4 at 7:12am and stayed there for 15min, then dropped at 7:27am. The MPPT battery current was zero during this time. (Lower right corner of the chart below)


Here is a zoomed view of the absorption cycle:


It seems the MPPT completed its absorption cycle at 7:27am and then switched to float, without actually feeding any current to the batteries.

At 13:04 the batteries had warmed up enough for the BMS to trigger the battery protect to close the circuit and you can see the MPPT battery current begin flow, but the MPPT remained in float.

Is this normal behaviour in this situation? I would have thought that once the batteries were reconnected, bulk charging would resume.


abegweit asked
abegweit commented ·

3 Answers

Appairage BatteryProtect HQ2132JXTXE et Orion Smart HQ2137XNUMZ par Bluetooth


Mon installateur m'a installé BatteryProtect HQ2132JXTXE et Orion Smart HQ2137XNUMZ.

Sous son contrôle, j'ai installé l'appli Victron Connect. Lors de la première utilisation dans son garage mon téléphone Galaxy A20 ne s'est pas appairé par le Bluetooth avec les 2 appareils.

Arrivé chez moi, j'ai reussi à appairé mon téléphone avec les 2 modules et j'ai pu changer les 2 mots de passe et voir les informations.

Depuis, j'ai renouveler l'accès plusieurs fois sans succès...

Merci pour toute information.

pri asked
Thiemo van Engelen (Victron Energy staff) commented ·

0 Answers

Disconnecting Large DC Loads

Hi! I've been searching here, but haven't found any discussion around this question.

I'm looking at setting up a large lithium house bank on a boat (800Ah) to drive both DC loads and a multiplus inverter and a VE.Bus BMS. I understand that the BMS should be able to switch the load off under certain conditions. The suggested route is to use a BatteryProtect, and the remote option on the Multiplus.

Switching the Multiplus seems straightforward, but switching the large DC load less so. Max DC ampacity for the load is roughly 600A, although the highest current draws are very intermittent — windlass (100A), electric winches (200A x 2). Even so, my understanding is that I need to switch everything off when indicated by the BMS.

The largest constant current ampacity I see for the BatteryProtect is 220A. While some loads are intermittent, when in use, they may be used for minutes at a time, so I think I must remain within the continuous current rating for the Battery Protect.

What's the best way to switch this DC load?

I've considered paralleling several BatteryProtects, both on the load and on the signaling circuits, but I'm currently leaning towards a 600A contactor with 4000A surge rating, despite the appearance that the signal from the BMS will likely need to drive a relay to provide the necessary current to the contactor.

Please advise.



pmolettiere asked
pmolettiere commented ·

7 Answers

Welches BMS für einen DIY Akku?


Kann ich neben meinen sechs Pylonech US2000 eine Batterie installieren und an die gemeinsame Busbar klemmen?

Da Pylon 15 Zeller baut soll es natürlich auch ein Rack aus 15 LFP daneben werden. Welches BMS können sie dafür empfehlen?


rossix asked

0 Answers

Zu hohe Ladespannung Batterie


Ich benötige euer Fachwissen und Hilfe.

Ich habe heute meine Victron Anlage zusätlich mit PV Panele in Betrieb genommen.

Dabei viel mir etwas auf und ich mach mir Sorgen dass ich meine Batterien zerstöre

Bis Dato wurde meine Anlage vom Netz 230V versorgt, heute habe ich eine kleine PV Installation hinzugefügt falls das Netz mal ausfallt und das ganze als Inselanlage funktioniert.

Nach dem Anschluss der zwei PV Module wurde der MPPT 100/30 aktiv, was auch so sein sollt.

Jedoch ist meine Batteriespannung sehr schnell hochgegangen obwohl die Batterien zu 100% geladen sind und mir die Anlage sagt "Lagerung". Am MPPT stand BULK.

Mich hat das etwas beunruhigt, da normal der Verbraucher (Kühltruhe) vom Netz versorgt wird und die Batterie auf 26,5V Erhaltungsspannung lauft und alle 7 Tage via Wechselrichter geladen wird.

Zu meiner Frage: Ist es normal das die Spannung an den Batterien mit einer angeschlossenen PV hoch geht?

Aktuell fällt diese wieder da der MPPT abgeschalten ist (Nacht).

Zur Installtation 24V 300A, 4 Bleibatterien á 150A Serie/Parralel verschalten.

MPPT 100/30 > 2x PV Platten 405W in Serie, errechnet mit dem MPPT calculator.

Victron MultiPlus Compact 24/1200/25-16

SmartShunt 500A zur Überwachnung der Batterie.

Bilder sind im Anhang. Danke für eure Antworten!


marcel123 asked
marcel123 answered ·

2 Answers

Smart Battery Protect on battery side of MPPT?

Hi every one

Now I have read everything I can find about Smart Battery Protect on battery side of MPPT and there are people who write it will work, and there are people who write it does not work, and the whole house will burn down.

So Victron who is right, I have found this drawing, where Victron uses it in just this way.

Best regards Jens



jens-due asked
Glen Carter edited ·

2 Answers

How to connect 2 batteries instead of 1?

We are unstalling a new system in our off grid house. The dealer sold us one Fortress eFlex 4.5kWh battery, but we ended up with two. So we want to install them in parallel, 48 volts (52 volts actually measured on them.) Since the original system was simple, the dealer did not include any battery combiners, protectors, or isolators. Right now I just have both positive battery cables hooked to a busbar and both negative cables hooked to a separate busbar. From those busbars, the heavy cables go to a VE panel box, and from there to Multiplus Ii 48 volt 3000 inverter charger. We have a BMV 515 smart shunt in the VE panel box, a Cerbo GX, a GX touch 50 display, a VE smart dongle and an150 85 MPPT solar controller. Plus 8 Canadian bifacial solar panels. So will our sytem work with just busbars, or do I need to add some sorta lynx system? What do we gain or lose by adding more components? I like the idea of the device that protects the batteries and shuts them off if we get down to 10%. Part numbers please, if you think I need to add something. Thanks!

junglehouse asked
snoobler answered ·

1 Answer

Remotely switch Battery Protect on and off through VRM

I can control my Multiplus through the VRM and a GX LTE whilst away from my boat which is great, but i would also like to control other loads that are fed through a battery protect.

Is there a way to do this?

sweyn asked
sweyn commented ·

3 Answers

Possible Reverse Current through SBP using MPPTs

God Day,

I am using a SBP 220 in line from my charging components to the LiFePo4 housing bank, three MPPTs and two Orions. Wired where the charge goes to the “In” and then the “Out” goes to the house bank.

The two thoughts I have on reverse current is:

1. When there’s no solar the MPPTs draw power from the battery bank to remain On. I’ve read this is such a little draw that the SBP is able to handle this due to dissipating heat. Even though everywhere in big bold letters we are told No reverse current from Victron. Yet they’ll show this same setup on their diagrams. With this being said, how much is too much? Could three MPPTs end up being too many? What about a fourth, or adding two Orions? All very little standby draw but still adds up, right?

2. Continuing that thought, what about the streetlight function on the MPPTs? Granted, I’m still trying to learn how that works but seems like the MPPT controls the Streetlight function through the means of a relay? Would that then draw power from the battery to operate the relay or signal it sends, in turn drawing power from the bank and through the SBP adding to the reverse current?

Just hoping to achieve a more accurate idea of what’s acceptable than my “should be good” current state of thought. Not trying to break an SBP or worse, start a fire on the boat or something.

mariner asked
mariner answered ·

2 Answers

Connecting Battery Monitor BMV-712 with Battery Protect BP-100

How can I connect the relay terminal of the BMV-712 battery monitor with a BP-100 battery protect? I want to disconnect the battery in case the capacity of the battery has reach a defined percentage. I only can programm the cut off voltage off the BP-100, but I want to use the capacity information from the BMV-712.

adversor asked
fredroni answered ·

12 Answers

How to store Victron Lithium Batteries

I have three 200ah batteries that have never been used. I have been storing them in a climate controlled storage. Should I be charging them periodically or are they okay to continue without any additional upkeep? What could I charge them with if that is needed? Thank you!

a3x5fan asked
Stefanie answered ·

2 Answers

Selecting a charger and inverter for a 100V/50Ah/5kWh LiFePo4 battery

A 5kWh 96V LiFePo4 battery fell into my lap, a it's a SonnenModul4. Ever since I've been studying up on solar systems, as I plan to go to Africa, to live and work from a solar powered camper, exclusively, for the next 5 years. I never thought I'd be able to put in such a powerful and reliable battery. This feels revolutionary.

I presume a solar system built around such a battery looks like this:

  1. a single string of 3 or 4 solar panels of around 40V each, each with 375W. They have to fit a 170x400cm roof area. During most of the day that should give me 750W or 1000W, ample.
  2. a MPPT charger with overcharging protection to connect the PV to the battery. It should be able to comfortably work with 160V DC in
  3. an inverter, to give me 230V from the battery voltage. at least 2kW allows me to cook without switching of appliances like the fridge. I could even run a basic air conditioning.

I suppose this battery has a BMS to re-balance the cells, but I don't know about any protections like overcharge or over-current (short-circuit). My questions:

  1. is the system complete? would I need anything else?
  2. what protections should I take care of?
  3. what devices would be recommended?
  4. maybe there is an inverter with an integrated MPP tracker?
  5. is there a way to run the inverter directly of the solar panels, switching to the battery only when needed?
  6. bonus: how to keep the solar panels cool (as they'll get very hot)?

Though I work with electronics, I'm still a newbie when it comes to best practices, the market and how to layout a system. Any advice would likely be taken ;-)

chromebin asked
nickdb commented ·

2 Answers


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