Multiplus II 5000 vs 6k5

Other languages Deutschsprachiger Bereich
,
1

Hello everyone,

I am currently setting up a single-phase system in which the MultiPlus II will be used as a battery charger (AC to DC). I am interested in achieving the highest possible charging power. I am now wondering whether the 6k5 can also be used single-phase. Until just recently, I assumed this would not be possible because, due to the VDE phase imbalance standard, even the 5000 model is limited to 4.6 kVA. However, I have now found the certificate Certificate-VDE-AR-N-4105-2018-11-EZE-MultiPlus-II-(GX)-24V-3k,-48V-3k-4k5-5k-6k5.pdf, which shows 4.56 kVA. I have also seen a few posts indicating that the 5000’s 70 A charging current is not fully utilized and decreases over time. As I am a beginner, I would like feedback on whether the 6k5 can alternatively be used single-phase and by how much higher the charging current would be in what would presumably also be a limited mode (4.6 kVA input).

Same in english: I am currently setting up a single-phase system in which the MultiPlus II will be used as a battery charger (AC to DC). I am interested in achieving the highest possible charging current.

Now I am wondering whether the 6k5 can also be used single-phase. Until just recently, I assumed this would not be possible because, due to the VDE phase imbalance standard, even the 5000 model is limited to 4.6 kVA.

However, I have now found the certificate Certificate-VDE-AR-N-4105-2018-11-EZE-MultiPlus-II-(GX)-24V-3k,-48V-3k-4k5-5k-6k5.pdf, which shows 4.56 kVA. I have also seen a few posts indicating that the 5000’s 70 A charging current is not fully utilized and decreases over time.

As I am a beginner, I would like feedback on whether the 6k5 can alternatively be used single-phase in Germany, and by how much the charging current could be higher in the presumably AC-limited operation (~4.6 kVA input).

Best regards,

Martin

2

You’re on the right track :wink:

graphic
graphic865×735 25 KB

Several single-phase inverters can be used to build a three-phase system. The inverters must be distributed evenly across all phases. All inverters use the same battery. All inverters communicate with one another.
Otherwise, the maximum connected power of 13.8 kVA (max. 4.6 kVA per phase) must not be exceeded

3

Hello Steffen,

I don’t want a three-phase system; I simply want to get the maximum out of one inverter. The maximum apparent power of 4.56 is below the unbalanced-load limit of 4.6 kVA and should therefore be fine, if I understand the figures correctly.

That would make the 6k5 Victron’s new top model for single-phase installations.

Can anyone else give a rough estimate of how much of an advantage it offers over the 5000?

An AI came up with an estimate along these lines for AC charging:

Comparison: MultiPlus II 5000 vs. 6k5 (AC charging only)

Device Internal charger Theoretical maximum Actual at 4.6 kVA
MP II 5000 ~70 A @ 48 V ~3.3 kW DC ~3.3 kW DC (the charger is the limiting factor)
MP II 6k5 ~100 A @ 48 V ~4.8–5.0 kW DC ~4.2–4.4 kW DC (the grid is the limiting factor)

Direct comparison (56 V)

Device DC charging power @ 56 V Limit
MP II 5000 ~3.6–3.7 kW Internal charger
MP II 6k5 ~4.3–4.4 kW 4.6 kVA grid

That would be an advantage of just under 20%.

Any other experiences or estimates from your side?

Best regards,

Martin

4

One more point for my understanding. Because of the 4.6 kVA limit, the 6k5 can only feed a maximum of 4,600 W into the grid on a single phase, right? The 6,000 W output would only be possible in off-grid mode?

5

I haven’t been able to test or observe it yet, but I also think the 6k5 won’t be able to maintain its charging power continuously and will reduce it after a while.

You probably won’t reach 100 A either with the German grid code and the associated power limitation.
But I haven’t been able to test that either, and I won’t have any time left to do so this year.

In grid-connected operation, the power ratings specified in the certificate should apply; only in island mode can the power stated in the standard datasheet be assumed.

6

Good morning Matthias,

if you get a chance to carry out such a 6k5 test in the new year, it would be great if you could also take a look (or have a listen :slight_smile:) at the noise level compared with the MP5000.

7

As a dedicated charger, an MP II ??? You should say what you’re actually trying to achieve!

Do you have a solar system? Or do you want to charge using “cheap electricity” ??? Then don’t forget that around 25–30% is lost through charging/discharging!

8

@Steffen Thanks for your feedback to start with.

Hi Holger,

Yes, I installed a 24.5 kWp system on my roof last December, with the panels distributed roughly equally across the east, south and west-facing sides, using its own (non-hybrid) inverter with 3 MPPTs. Because of the high level of self-consumption, I decided against a hybrid inverter of that size at the time (up to 2.4 kWh per day) and planned a separate battery inverter as a retrofit. That is now being implemented. At some point, I may also add a separate small PV system on a carport that has yet to be built.

The current system is working well so far. The lowest yields, on completely overcast winter days, are around 5 kWh, while on the best days in summer they reach 174 kWh. So far this December, we have averaged 20 kWh per day, although I think the average will be more like 15 kWh by the end of the month. Last January, the average was 19 kWh. The system supplies a four-person household with a heat pump. Since I only run the heat pump during daylight hours, current overnight consumption is relatively low, at around 100 W. However, I would like to let the heat pump run a little more gently and extend its operating window into the hours of darkness. At the moment, it needs around 10 kWh per day on days with little sunshine and average outdoor temperatures of 0°C. Although the overall system in the house is probably already very efficient in terms of efficiency, I would now like to indulge my urge to tinker a little further, take some of the strain off the heat pump (50% maximum limit at 800 W) and cover some more of the overnight consumption.

Now to the planned system, which has already been ordered in full and is either in the garage or on its way there: 2x DIY Battery Box, 32x MB31 A+, now also the 6k5, plus accessories.

As for why I chose the 6k5: the aim should be to get as much electricity as possible into the batteries on sunny days in December without over-dimensioning the charging system, for example with an unnecessary three-phase system (because of its self-consumption). At the moment, on sunny days we get around 6 hours above 4 kWh, with peaks of up to 7 kWh around midday. At midday, when the sun is at its highest, we heat the hot water once. Before and afterwards, the heat pump runs as a heating system. Overall, it would therefore be good to have a charging capacity of, say, up to 5 kWh. The MP II 5000 was a little too small for this. The 6k5 appears to be considerably better, particularly if it turns out that it does not throttle the charging capacity because of heat build-up or anything else.

I am sure I will have one or two more questions over the coming weeks. I will also be happy to report on my experiences.

Best regards,

Martin

9

So far, I have installed two three-phase systems with the 6k5: one off-grid system (on a boat) and one as an ESS.

Unfortunately, the boat is offline, so I cannot say anything about its power profile. The 6k5 units there are only used for the starting current of an electric motor; otherwise, the load is not particularly high.
The rest of the consumer installation for the ESS is unfortunately not ready yet, so commissioning has not been possible and the units have not really been running yet. That will not happen until the new year.

As far as noise is concerned, however, I could not hear any major difference between either system and the 5000 model.
The 50 Hz hum has always varied somewhat from one unit to another—sometimes louder, sometimes quieter.

You should still avoid installing the units in your living room if possible. When installing them in the cellar, you may want to use anti-vibration wall plugs or otherwise isolate the units from the masonry to reduce the transmission of structure-borne noise through the walls.

If you are standing directly in front of them in the same room, the 50 Hz hum will always be noticeable.

10

Hello Matthias,

Do you have any updates on the ESS with the 6k5?

I’m particularly interested in its performance when operating on-grid. Are the three 6k5 units in the 3-phase ESS with Gridcode D really limited to 13.8 kVA? That would hardly be any different from the 5000 model. And if so, does the 13.8 kVA refer to both feeding into the grid and drawing from it (charging)?

Best regards,
Olaf

11

Hello,

After four months, the DIY boxes were finally delivered last Friday and the system was assembled. MP2 6k5, Cerbo GX + 2x DIY Battery Boxes with JK19 BMS and 16x MB31 and VM-3P75CT each, connected single-phase.

Basically, charging and discharging work. DVCC is enabled. What I still find strange is that neither BMS, or the master BMS, is displayed in the Cerbo.

Everything is connected in this way.

PXL_20260316_081845471
PXL_20260316_0818454711920×3413 844 KB

Grey to the MultiPlus. Orange to the Smart Meter, blue to the DIY boxes.

PXL_20260316_081818624
PXL_20260316_0818186241920×1080 348 KB

The protocols are set to:

PXL_20260316_081833213
PXL_20260316_0818332131920×1080 307 KB

I have the Type A cable. I read that it should work, but that Type B is recommended?

The VE.Can connection is set to 250 kbit/s in the Cerbo GX.

I’m not sure what other information might help, but perhaps someone has an idea.

Best regards

Martin

12

Have you tried 500 kbit/s? Most batteries use that.

13

Yes, I’ve just found it. I wasn’t quite sure yet which connection was CAN 1 and which was CAN 2… at first I thought they were the two connectors next to each other. I’ve just checked my own photo and seen that the BMS is connected to CAN 2. I’ve now set that to 500. Thanks, Matthias.

So, a summary for everyone reading this:

Remote Console: under Services / Ve.Can Port 1, Smart Meter and Cerbo are shown under Devices at 250 kbit/s, and Ve.Can Port 2 is now set to CAN-bus BMS LV at 500 kbit/s

14

To return to my original question at the beginning of the post: what charging power can the 6k5 provide on a single phase? I now have some initial findings on this too. Throughout the day, the sky cleared up from time to time. In the VRM Portal, the displayed charging current then rose to as much as 109 A at a battery and inverter temperature of around 12–14°C. Peak output was around 5,880 W at approximately 53.5 V. I can’t yet say how long the system maintains this current, due to the constantly changing weather conditions.

Best regards

Martin

15

You’re using the MP-II-6k5 purely as a charger, and at 5.88 kW you’re well above the 4.2 kW threshold above which, as far as I know, you have to register a controllable load with the network operator. This isn’t bureaucracy for its own sake; it’s intended to ensure grid stability.

16

Hello Tom,

I was wondering about this too. As I understand it, setting the GridCode should in principle limit the MultiPlus to 4.6 kVA. Is that not the case?

Best regards,

Martin

17

The 4.6 kW relates to a different issue, namely the inverter output. It must never create a greater load imbalance between two phases than these 4.6 kW. That would always be prohibited! In your case, however, this is about drawing power from the grid to charge the battery, and there is no limit for that—only a notification requirement, so that the grid operator knows what loads to expect on its network. So you can certainly draw 5.88 kW for charging, but the device must be installed and registered by an electrician, and it must be remotely controllable.

When operating on a single phase and configured for the German grid code, your MP-II should have a maximum inverter output of 4.6 kW. The question that remains open is whether this limit is lifted when operating on three phases.

18

Hello Tom,

so this is about the power output from the MultiPlus, which is then limited (inverter power). Just for your information, although I have no idea whether this changes anything regarding your point: I don’t import power from the grid to charge the battery. The power comes from the non-hybrid inverter and its 24.5 kWp system. Nevertheless, I presumably still have to comply with the phase imbalance limit, don’t I? Or does this not apply in this type of connection?

Best regards,

Martin

19

According to the datasheet, it can actually only supply 100 A of charging current to the battery…

20

Inverter_AC
Inverter_AC1438×756 97.2 KB

Battery_Power
Battery_Power1553×772 108 KB

Just for information. The two negative peaks are about a 10 kW load in the house.