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Multiple inverters on one GX and battery

I am looking at installing a system for 5 property's on the some site but have separate energy meters but are owned by the same company, they have panels already installed, they are wanting one battery back and backup genset, can you put one multiplus 48v 5kva for 4 of the properties and one quattro 10kva for the main house on one battery bank with one GX device. Thanks in advance

matthew-burnett asked
matthew-burnett edited ·

1 Answer

Phoenix 12/800 car battery


1. I just bought a 12/800 Phoenix. For now I only have a 12v-30amp car battery available.

Can I use this battery with this inverter?

2. I also have a 12v-7amp Blue smart charger. Can I use this on a 12v-105amp battery when I get one eventually?

Thanks from Africa!

finhobbyist asked
finhobbyist answered ·

2 Answers

Battery type


Can anyone help me to work out the right settings for my battery om the Victron app? Screenshot of my battery datasheet: it's a Vision 6fm100d-x


danjorourke asked
christern answered ·

1 Answer

Battery combination

I want to ask such a strange question, is it possible to combine Pylontech batteries (4x3.6kWh) and 2xLifePo4 280Ah on a common connector??? .
What I noticed in the documentation is that the pylontech charges the batteries at 3.467V (52V) during absorption and the Float charges at 3.4V (51V).
My point is that I have both types of batteries and I would like to use their capacity. When they are connected in parallel on the bus and the parameters are set in the BMS for 280Ah batteries, it should work safely.
Basically the charging would be controlled by the Pylontech BMS or not controlled by the Pylontech BMS and the Pylon BMS would adjust the charging current and voltage by itself like the other two BMS now, only the toy cables that come with the Pylontech can handle 100A continuously AND the charging from the MPPT must not exceed 100A, so I won't use the potential of the panels :).

So this would be a question of how long it would last and if it could be solved or if two more batteries could be charged, I suppose not, but maybe someone here has already tried it :)
Or I can use SmarShnut and set it to 856Ah, plus Abs.V 52V, Float.V51, Abs.Time 1h ...

Crazy or not??? : )

Thank you for your opinion

Juraj Nikolov asked
Alexandra commented ·

1 Answer

SmartSolar MPPT 100/20 does not allow starting the inverter?

I created a small solar system on my balcony, consisting of a single 300W panel, 100/20 MPPT, 200Ah LiFePO4 and 2,000W inverter - made for educational purposes.

For few weeks I have been experiencing a specific problem:

During evenings (small or no light), when the converter is off, I am not able to start it. Battery is fully charged but it acts like it was flat = no response. I feel it is the Victron battery charger causing it…

The situation is back to normal in the mornings when more Volts are generated.

Has anyone experienced the same problem? Can there be something wrong with my Victron?

An addition observation: at evenings, in the Victron app I can see the voltage fluctuating (up to few Volts), but no Amps. There is an additional note popping up and disappearing: “why is my charger switched off?”

Please help. Many thanks for help.

depalma asked
depalma commented ·

2 Answers

Phoenix 24/3000 - Erfahrungswerte Batterie-Erneuerung LiFePo

We would like to replace our old AGM batteries (600 Ah) with modern LiFePo batteries in our garden house (6panels, 1.2kWp power, Phoenix 24/3000 and a MPPT 100/50 BlueSolar). Can anyone share their experience / recommendations here? Thanks a lot

offgrid-see asked
offgrid-see commented ·

0 Answers

Enabling nighttime export from DC-coupled battery inverter to grid (in addition to daytime export from AC-coupled PV inverter)

I have had a simple grid-tied 5kW PV system for some years.

I have recently added 3 x RedFlow ZBM2 batteries, which means a total of 30kWh, but an available usable 20kWh at any instant (allowing for maintenance strip cycle of these batteries).

I want to reserve 4kWh for my own grid-failure backup use, and export the additional 16kWh to the grid each night. I have rooftop capacity for charging the batteries.

Once the system is configured to export this additional 16kWh to the grid each night, I will know how many more batteries to install, with the ultimate goal of exporting 5kW (1Ø household limit) to the grid constantly, day and night.

As far as I can tell, I have had all the necessary hardware installed, including:

  • MultiPlus-II GX 48|5000|70 battery inverter;
  • SmartSolar MPPT 250|100 MC4 VE.Can charge controller (for the DC-coupled PV array I added); and
  • The associated accessory hardware.

So far, the system is working correctly, charging the batteries, and providing backup power for the house, but the additional grid export is not happening yet, and I'll make the system available to the utility for FCAS once I've sorted the export out. I have not yet seen any additional grid export at all - my usual daily averages of 35kWh production / 21kWh consumption have continued unchanged.

Any suggestions for getting the additional export from the batteries happening?

el-gallo-azul asked
nuxland edited ·

2 Answers

Battery voltage drop when high load is connected


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

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

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

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

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

Thanks a lot,




the-salmon asked
nickdb commented ·

3 Answers

Battery selection

I have purchased Multiplus II 230V 5kVA inverter charger to overcome power cut issues of about 3-4 hrs. Need to know the suitable battery for this. Lead acid or LeFePo4. Any good brand is ok.

rabeendra asked
Matthias Lange - DE commented ·

2 Answers

2V Battery Damage


Running 24V system with 12x 2V 1500ah Mastervolt traction gel batteries, all on their side. Batteries are connected via connector plates Inherited this ESS, it's located under the house on clay soil and some structural plywood. 100kg each, not surprisingly the ground has settled a bit over the last two years and the top two middle batteries have slid back. The terminal connection held strong and the plate/terminals have been pulled out a couple of centimeters.

Voltage on the other 10 are all reading fine and balanced, but the two damaged ones were less than 1V each. They've obviously discharged but haven't been able to charge up to the same level as the rest of the system. Now the system sits at about 26V with the sun on and balances out at about 20.5V. I've disconnected the two damaged batteries and there is no difference in the performance of the system.

The question: best way to fix? Seems like battery balancers (active) would take too long and likely mess the other batteries up. My current plan is to run a 20V system until the working 10 discharge down, reconnect damaged batteries and charge up, disconnect damage batteries and discharge the 10, on and on until the 2 damaged ones are back at an acceptable level.

Another idea was to try and trickle charge the 2 batteries separate to the rest of the system, but nothing in the market to charge 2V or 4V systems, and I'm worried that hooking up to a trickle charge solar panel would be more trouble than it's worth? Not going to move them out (it's very, very hard and inaccessible) but could get some looong wires from a small panel. Would monitor this rather than using an MPP controller.

Anybody with experience on this one?

Leon Keefer asked
snoobler commented ·

1 Answer

Are Fuses or Breakers Necessary Between Battery and Lynx Distributor?

In my set-up the 4/0AWG wires that connect the batteries to the [Battery Bank] Lynx Distributor do not feature fuses. There are fuses internal to the Lynx Distributor, but the wires are effectively unprotected until they reach the Lynx Distributor.

Of course, I’ll keep those runs as short as possible (less than two feet long per wire/conductor) but it still seems weird to me to have a wire run unprotected.

Should I have an MRBF, or similar, fuse directly on the battery terminals?

Should I be using a different fuse or circuit breaker to protect the wires between the batteries and the Lynx Distributor, or is the system safe as it's currently designed?

The wiring schematic in the Lynx Smart BMS doesn't show any fuses in that location.

The example schematic on the Victron Support site doesn't show any fuses here (

On the other hand, this post ( on the community makes me think I will need protection, if what that discussion says about Lithium batteries arcing past MEGA fuses is correct.

midwest-van-man asked
midwest-van-man edited ·

0 Answers

What's Your Battery Round Trip Efficiency?

I've always wondered how we fared compared to others, either Pb or Li etc with our second hand Hoppekke 2v Flooded lead acid cells, this will not be very scientific and quite a few factors will skew the results, but it would still be interesting to compare for fun.

We have:

Hoppekke 930Ah (C5) x 24 = 1,860Ah (C5) @ 24v / Quattro 8k (batteries probably 4-5years old)

VRM / Connect Battery History:


For the lazy maths calculation:


So for my 5 year old-ish FLA's roughly 85%

That's mine, what's yours!? Imaginary prizes for the most efficient and the least efficient :)

Al asked
Marco Nijholt answered ·

8 Answers

I want to extend Pylontech 2000 Batterie to 500 Ah

Hello Team,

I have Installed 3 Phase Multiplus II System with and everything is working fine.

I using 6 x Pylontech 2000 it s working fine. But now i want to add another 4 x Pylontech 2000.

I have 300 Ah thats + 200 Ah I write the new number into the multiplus ok.

How do i make the bus connection and the jumper adjustment?

since the cerbogx does not recognize the pylontech 2000 with the recommended adjustments from the pylontech 2000 manual.

pointer asked
klandos answered ·

3 Answers

Read energy charged/discharged or power from Pylontech


I am trying to figure out how much energy is storged to and retrieved from the battery on daily basis. Could somebody help me with figuring out how to read this values from the CerboGX? It also would be fine if I get the active power reading of the battery so that I can do a rieman calculation to figure out the energy.

I tried to read modbus register 301 and 302 on slave 225 (my Plytontech) but it always returns zero. On the CerboGX itself (slave 100) the registers do not seem to exist at all. So how to get the information?

Thanks in advance

sesshoumaru asked
shaneyake answered ·

2 Answers

Direct cable link between House and starter battery negative posts.

Apologies if this is a dumb question, but is there any reason not to directly link the two battery negative posts with a short cable rather than linking through busbars as shown on the various Victron circuit diagrams.

I ask because my batteries are co-located and it would just be simpler.

sweyn asked
sweyn commented ·

2 Answers


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