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multiplus in parallel

MultiPlus reported amps under reported when generator running.

I'm running two MulitPlus 24/3000/70-50 120V in parallel. firmware v482.
When the multis inverting the AC-OUT Watts is close enough (+- a few percent) to V*A = W.
With Honda EU2200i generator running:
AC IN: rough average V*(A*1.6) = W
AC OUT: rough average V*(A*2.56) = W

Input limit: 5.0A
Overruled by remote:

Inverter Power Assist: Off

With generator running
AC IN 1:
Voltage: 120
Current: 9.5 (15.2\9.5=1.6)
Power: 1826W
Frequency: 60.3Hz

Voltage: 120
Current: 3.8A (9.725\3.8)=2.56)
Power: 1167W
Frequency: 59.9Hz

Voltage: 26.69V
Current: 22A

As long as I set the Input limit to 1/3 of what I want the maximum watts pulled from the generator, it won't overload the generator. Setting it at 4.3A in general ensures it never pulls much more than 1,800W. At 5W it will creap up towards 1,900W and bounce between there and 2,100W at 120V.

I did measure same length 5' (1.5M) and torque down the 6 AWG(13.3mm2) THHN copper from busbar to the two Multi's the same. However, amp meter shows load is different about 1:3 between the two Multi's. Wondering if that mismatch in load is the cause of my issues? Unsure what to do other than maybe change out the THHN wire to Ancor Marine 266 strand tin coated copper.

Just so strange that the AC OUT L1 current is so far off when in passthru vs. inverting.

Thanks in advance for any ideas.

victron asked
victron edited ·

2 Answers

Existing Phoenix inverter, wish to purchase and add a MultiPlus in parallel.

I have an entirely off-grid installation with an existing Phoenix (48V/5000VA) 230V inverter and wish to purchase a MultiPlus (48V/5000VA) 230V inverter/charger to be installed in parallel configuration. The primary goal is redundancy (in case one inverter fails) and to enable charging of the batteries (if needed) from a 3kW generator (continuous 2.5kW capability). A secondary purpose would be to increase the power output capability.

I know there can be compatibility issues that have to be taken into consideration with paralleling.

The original firmware that the Phoenix inverter came with was 2624413. I have updated the Phoenix inverter from v413 to the latest v482 firmware version today, so if the MultiPlus doesn't come with the latest firmware I am more than capable of updating that to the same version.

I would be seriously concerned if a new MultiPlus didn't come with firmware starting with 26 (VE.Bus - new microprocessor, 230VAC) now, but I've cross checked the list of models document and 2624 is listed as "MultiPlus 48/5000/70-100 (+EasySolar)". It is literally the only model on that list that is 70-100 (70-amp battery charging and 100-amp AC transfer capability).

Am I correct in concluding that if I purchase a 2624 (i.e. a MultiPlus 48/5000/70-100) and update the firmware to v482, if needed, then it should be capable of being paralleled with the existing Phoenix inverter?

Second question is, if I was to purchase the MultiPlus and it failed to parallel could I instead fall back on a configuration to feed the AC output from the Phoenix into the AC input of the MultiPlus to increase the output capability?

I already have a changeover switch in the configuration to change the house AC supply from the Phoenix to the generator and could easily reconfigure that output to feed into the AC input of the MultiPlus instead. I'm not sure how the MultiPlus would handle that changeover from the Phoenix to the generator, I suspect it wouldn't too well, and it might get more complicated if the "Dynamic current limiter" setting needed to be enabled for the sake of the generator.

In the worst case scenario, I would feed the Phoenix output into the MultiPlus input and keep the inverters and generator separated by the changeover switch. This would provide the redundancy and increase in power capability. In this case, if I wanted to meet the goal of charging the batteries I would need to purchase a Skylla 48/50 TG Charger, which is practically doubling the cost as it's price isn't much different from the MultiPlus and it'd probably more beneficial to just buy another MultiPlus and just use that purely as a charger (if it can be configured that way). Really don't think I could stretch the budget to handle this.

My preference would be to parallel the Phoenix and feed the generator into the MultiPlus charger, this would eliminate the need for the changeover switch entirely and I think more likely to meet all the goals, but it would also be nice to know that even if I do everything right, there was a fallback position if the paralleling did not go as planned.

Happy to take advice if anyone has a better option to achieve the goals.

william-croft asked
offroadflow answered ·

5 Answers

Can I connect 2 different Multiplus II in parallel mode ?

I have a Multiplus II 48/3000 and I can get a Multiplus II 48/2000. Does they are matching together in parallel mode ?

volkerjuenke asked
volkerjuenke commented ·

1 Answer

Parallel Multi question


Im planning upgrading to a parallel system. 2 multiplus 3000/24/70 (Gen 1) . I can confirm the following:

Both units are identical

Both units have the same firmware

Relevant VE config changes will be done when needed

Connected to the primary unit currently is a 150/70 MPPT and a 24v Battery + Venus GX and BMV.

i understand the DC cables must be of same lengths and gauge (DC bus will be used)

My questions :

Can i bridge the AC input feed to from the Inverter 1 to power inverter 2?

Can i bridge the AC output feed to inverter 1 to power the loads ?

Does AC output 2 still work independent or does it also have to be bridged ?


denzel asked

0 Answers

Parallel MultiPlus-II current sensing

I have an ESS installation with two 48/3000 MultiPlus-II inverters in parallel with grid feed-in disabled. The ESS Grid setpoint is set at 50W, but I experience incrementally higher (up to more that 400W) grid consumption as the Multi’s power output increases. I assume this is due to slight imbalances in the internal current sensors and/or cabling? Can this be resolved with an external current sensor (MultiPlus-II Current Transformer), and will a single sensor connected to the primary Multi and measuring upstream be sufficient? Note: The utility grid meter is sensitive for grid feed-in and disconnect when sensed

cobus-lotter asked

0 Answers

2 x Multiplus 2 48/3000 (parallel on phase 1) in ESS: grid setpoint not reached


I am using 2 x Multiplus 2 48/3000 (parallel on phase 1) in an ESS configuration with a Pylontech Battery US2000b+ (9.6kwh total) and a Venus device with EM24DIN. There also is a Fronius Symo 15-M AC coupled inverter with 10kwp PV connected.

All this in Germany on a 3Phase grid ("Schieflast" is avoided by other measures).

The second Multiplus was only installed yesterday, since then I observe that the grid-setpoint is never reached, there is, especially on battery, always a much greater consumption from the grid than set.

Grid Setpoint is set to 10W, true average consumption from the grid is almost 200W all through the night. As I stated: this is only true since the installation of the second multi.

If I adjust the setpoint to -200W, consumption drops but as soon as the solar kicks in during daytime I am exporting more than I want.

What could be the reason?

Thank you very much!


jfleissner asked
dennis commented ·

1 Answer

MP II drop voltage from 230 to 220v

Hello world

I have a 3 phase DC coupled offgrid installation with 400Ah Battery Bank. one of my inverter is giving 220 V on output with small to no load on this phase where the 2 other give 230.. and it goes on overload everytime

i check the wiring and everything is ok

Thank you for your help


redsam asked
Alexandra edited ·

2 Answers

Parallel 2 Multi 3000's

I want to install 2 Multi 3000's (parallel) in my RV and the RV has 50A service with a 50A dual pole main breaker. My system is 12VDC. How can I feed AC to both multis? By that I mean if I put 1 - 30A breaker on each side of the 50A main,.. with split phase I'm inputting 240V (NO NO!). If I put 2 - 30A breakers both on the same side of the 50A I'm potentially overloading one side of the service. FYI, nothing in the RV runs off of 240V. I hope I've stated this correctly and hope there's an easy solution for the issue.

glenn2387 asked
marekp commented ·

1 Answer

Dual Victron Multiplus, same battery bank, separate AC out.


I need some assistance. I´m installing a setup composed of a battery bank (lithium), 2 smartsolar MPPT, 1 Cerbo GX, two Multiplus II - 48/5000. (240VAC)

The system is installed and it is working fine, but I can´t find a way to only have one inverter/charge working. I understant that when configuring the inverters in split/parallel/three phase, if one shuts down, the other one also turns off.

But one this case, I don´t need to combine the power of both inverters. I have the AC-out´s connected to a swich on the AC switchboard in which we use either one inverter, or the other. So we would like to use the inverters as indepent as possible.

Right now, I have them connected to the Cerbo GX, each with their own VE.BUS cable. I´ve tried chain one VE.BUS cable from one inverter to the other and then to the Cerbo GX, but it is the same, I cannot use one inverter without the other.

Is there any workaround to this? We just want to have more redundancy with the setup, we don´t need to have the combined power of the inverters.

nuno-silva asked
nuno-silva commented ·

2 Answers

Multiplus 48/5000 Slave unit irregular flashing

I have just setup two identical Multis 48/5000 in parallel. The firmwares are the same and all AC & DC cables, breakers, etc are symetrical. Under 7-8KW load 30 mins I am getting no overload warnings so the two units appear to be working in parallel just fine. Unfortunately the slave unit is flashing green between MAINS ON & INVERTER ON whilst the master just shows constant INVERTER ON. I have tried re-programming them and swapping master with slave and once again the slave unit flashes green between MAINS ON & INVERTER ON so both units flash in this sequence when they are programmed as slave. My question is this difference in lights normal as the units appear to be working fine. Grid input is not yet connected

rithym1964 asked
rithym1964 answered ·

2 Answers

Setting up 3 phase/2 parallel system - fixed


I am trying to set up 3 phase/2 parallel system based on 6 MP-II.

How to set the master and slave in each phase?


marekp asked
marekp edited ·

1 Answer

Parallel AC Multiplus II injection algorithm problems

Hi, I have something strange in a configuration of a system that works with two inverters in parallel. This happens only in injection zero modes and limited power injection.

Hardware system:

- 2 Multiplus II 48 5000 70

- 2 SmartSolar MPPT 150 100 Ve.CAN setup

- 1 battery bank of 3 parallels Pb-C = 600 Ah - 48V

- 30 Renogen 340W setup as: 3+3+3+3+3 MPPT N º 1, same at MPPT N º 2.

- OctoGX


Last firmware: 2623481.vff

OctoGX version 2.63.

(the same configuration tested, and same problem on 2.60 version of the OctoGX, and firmware 2623477)

VE.Bus System Configurator:


VE.Bus Quick Configure:

The configuration of the inverters is the same, (in the attachment you can see the configurations), and the ESS Wizards were also load separately as the documentation explains:

Configuration files:

Datasheet externals brands:

Renogen lead carbon battery.pdf

In the video you can see how when you change the configuration to limit the injection or set it to 0 injection, the system begins to oscillate, connecting and disconnecting the part of the solar regulators, It is noticeable in the sound of the inverter as the winding makes an effort to connect and disconnect, obviously this is currently injecting because I could not leave it working that way.

I posted the same on Spanish questions forum but still have not answer, here the link Pregunta en español

Sorry for my english!

Fernando Mazzaferro asked

0 Answers

Two different models of Multiplus in parallell

Is there a way to Connect two different models of Multiplus in parallell in the same system?
My system contains of Venus GX, two MPPT charge controllers .
its all BMS controlled (REC Q-bms 16s)

jgy67 asked
jgy67 commented ·

2 Answers

ESS: Can Pylontech batteries limit inverter output during day when SOC 100% and loads run off solar?

The site has a 7200w solar array.

20 x 360w solar panels

250|100 MPPT


2 x 5kva MultiPlus II inverters in parallel.

3 x US3000 PylonTech (under Victron recommendations)

It is an ESS system. (Optimized with Battery life)

after SOC is 100% , when consumption goes >2500w in the day, the panels don't cover the consumption. Can this be because of the continuous discharge rating of the Pylontech batteries? or is this not the issue?




@Guy Stewart (Victron Community Manager) @Johannes Boonstra (Victron Energy Staff) @mvader (Victron Energy)

Can you help, been struggling to find the solution to this problem.

jond asked
jond edited ·

2 Answers

Multiplus parallel schalten

Ich habe einen Multiplus 24/500 und einen Multiplus 24/800 die parallel konfigurieren möchte. Wenn ich die beiden mit dem VE Bus zum CCGX verbinde kommt einen Fehlermeldung. Mit der VEBus Config Tool SW erscheint die Meldung, dass die Multiplus nicht gefunden werden. Einzeln kann ich sie aber finden.

Kann man überhaupt einen Multiplus 500 mit einem 800 parallel schalten?

ernst asked
ernst answered ·

2 Answers


Bonjour, j'ai une installation en mode ESS avec 2 multiplus 3000VA 48V 35-50A. La configuration avec VE.BUS Quick configure pour 2 Multi parallel, ensuite dans VE.Config avec l'assistant ESS...

Le système fonctionne bien en hors réseau mais dès lors que je couple l'entrée AC IN réseau le système s'arrête avec erreur code 24... - Mesure de la résistance de l'onduleur Master (Neutre In / Neutre out = 0) Mesure de la résistance de l'onduleur SLAVE ( Neutre In / Neutre Out = > 380 ohm).

Quelqu'un à déja eu ce problème ?

michel-tahiti asked
Thierry Cortassa (Victron Energy Staff) answered ·

1 Answer

Parallel Multiplus DC cable length

I will have one Multiplus closer to the negative busbar, and the other closer to the positive switches. Is it okay if the sum of each set of cables (positive plus negative) is identical, even if the individual cables are not? In other words, Multiplus 1 has a 50cm negative and a 100cm positive, and Multiplus 2 has a 100cm negative and a 50cm positive. I believe this is okay since the total resistance will be the same.

jverret asked
jwfrary answered ·

1 Answer

Parallel connection of Multiplus II, ESS, several houses to a common grid connection


I need help judge, whether this connection will work. The requirement is, no overflow of energy into the grid. The premise is that solar energy will only be transferred between houses.

Thank you in advance for the consultation


jkalous asked
jkalous answered ·

2 Answers

Correct setting for 2 MultiPlus Inverter outputs

I have 2 MultiPlus 3000 watt units to power my sailboat 50 amp 240 Volt USA type panel, one inverter for each ac line. When inverting the units work about 5 to 10 minutes and then have a synchronization/timing error. It does this using only single phase 120 volt appliances on each output line or using two phases such as the 240 volt hot water heater. I am not exceeding over 2000 watts on either inverter line. Current setting is for Dual Phase 180. L2 Floating with return to original phase. I have 3 x 300 amphour VIctron lithium batteries for the DC source and 1200 watts of solar inputing through 3 Victron MPPT units.

Should I change the L2 setting to Fixed or L2 Floating only without return to original phase?

pegasus2009 asked
Kevin Windrem commented ·

2 Answers

Marine charge current and shore power breaker control with CERBO GX

I have a recently installed Victron system consisting of two Multiplus units running in parallel, a BMV712 battery monitor and a CERBO GX.

The system runs wonderfully but I need to limit the charge current while the engines are running since I have a large engine driven alternator. I also need to limit the shore power breaker size setting when plugged into shore power.

I can perform both of these functions using Assistants in the Multiplus units, but that is not without challenges.

My first question is can I use a digital input on the CERBO GX to limit charge current in the multiplus units?

Can I use a digital input on the CERBO GX to change the shore power breaker size setting?

If the answer to those questions is No, then I have another couple of questions.

If I use an assistant on the Multiplus to use a digital input to limit charge current, does that assistant require a separate dry contact to create the same function in the slave multiplus? Or will the master Multiplus communicate with the slave multiplus to limit charge current from that one as well?

The other question is if I use an assistant on a multiplus to change the shore power breaker setting does this take away my ability to change the shore power setting from the CERBO GX display?

Thanks!, and here is a VRM screen shot of my system as configured.


blskevin asked
blskevin commented ·

3 Answers

Multiplus parallel zero load power

Is the zero load inverter power of a paralleled Multiplus system the sum of the individual zero load draws, or is it the same as just one Multiplus?

jverret asked
Matthias Lange - DE answered ·

1 Answer

Dual sources, one battery, one load two Multiplus, how to configure

I have purchased and am installing today on my boat...

2 multiplus inverter/chargers

1 Cerbo + display

1 712 battery monitor

I actually already installed a couple weeks ago, the Cerbo, display and battery monitor and am happy with them.

My boat has...

* one battery bank that can accept 200 amps of charge current.

* Two shore panel feeds that may or may not be in phase depending on the harbor I am at. These also can be switched to generator through interlocking breakers.

The AC input to the multiplus units will be from breakers in the shore power panel (s).

* One single phase 30 amp dedicated inverter panel.

Here is my challenge. I could pretty easially set the multiplus units in a parallel master/slave configuration, but I would have to use only one shore power to feed both multiplus units as to avoid out of phase sourcing.

I would prefer to set the system up to have only one inverter feeding my inverter panel at a time. I do not need the combined output of two multiplus inverters. I could do this through a A-B switch.

Then I could AC power the multiplus units from the two separate shore power panels. This setup would provide redundancy of shore power, plus redundancy of inverters (through the a-b switch), and redundancy and increased charger capacity.

The question is howe to make this work and display correctly on the Cerbo display? Is there anything special I need to do with the configuration tool to have the chargers work together?

My thought is that with the same charge profile the charge functions would be just fine as “separate“ systems, but I am concerned how to make the Cerbo display show one battery bank with both multiplus units.

THANKS!!! for the help!

blskevin asked
blskevin answered ·

2 Answers

mppt charger in parallel not syncronized

we have a system composed by two victron mppt charger working in parallel not syncronized as per victron datasheet . in this case the charging phase of the two charger will be not the is safe for the battery?what do you suggest?

corpa asked
corpa commented ·

3 Answers

Are these two multiplus compatible for Parrallel


I have 2 multiplus II with the same PN (PMP482305010)

But the SN are different :

- HQ1918*****

- HQ2016*****

When I look on the this forum I understand first that HW is defined by SN, but now it look they cannot accept the same firmware because of SN starting with diferent digit (19 vs 20)

Are these 2 multiplus not compatible for using in parallel on a single phase?

Note: I just buy these 2 multiplus... I did not think it could be an issue on compatibility.

Thank you in advance for your answer/help.


Arnaud B.

[moderator's note: edited to remove last 5 of device SNs]

arnaud-b asked
Matthias Lange - DE answered ·

2 Answers

à partir de batteries, produire du mono ou du triphasé?


j'ai 3kWh de batteries, un multiplus 24/5000/230 pour éclairage, petit matériel électrique monophasé. J'aimerais faire fonctionner un razbot-dégauchisseurs triphasé à l'occasion.

Je suppose qu'il faut 2 autres multiplus et un bon paramétrage.

Les mono et tri peuvent-ils fonctionner en même temps?

Lionel SEYDOUX asked
Stef answered ·

3 Answers

old phoenix multi 1809149 hex not charging


A family on the canal has asked for my help. they had 2 paralleled phoenix multis,both 18xxxxx firmware. Now they are trying to use one as a stand alone unit. the unit inverts but does not charge or pass through 230v. it shows 230v input in ve configure.I am using mk2 usb interface,and can change settings successfully but just cannot get it to work. the transfer switch clicks like its ignoring ac. incoming power all good. currently sitting on the bench so not wiring issues. configuration seems to make no difference at all. has anybody out there got firmware for 18xxxx version family?


paultheboat asked

0 Answers

Parallel Multiplus 12/3000 120-16 and12/3000 120-50 poosible?

Hello, is it possible to parallel a Multiplus 12/3000 120-16 which is since two years in use with a new multiplus 12/3000 120-50 ?

Thank you for Answers!

pedroaspre asked
pedroaspre answered ·

2 Answers

Can 2 multipluses be wired in parallel to provide double charging and inverting capacity?

Help! I’m about to buy 2 120v 3000w inverter chargers for my boat refit. Until this morning I believed I could parallel both the charging and inverting functions. This morning I read on this forum that this is not possible.

I.E. in a parallel installation only one charge current would be sent to the batts even if both are plugged in to shore power. Is this correct?

I’m building an inverter based boat that will have all AC powered through the inverter so it’s very important to me that the batteries get the most current possible on shore power.

Also, when paralleled and on shore power can I only use the input from one multiplus?

On my boat I have dual 30 amp shore inputs which I was planning on running one to the first multi and the second to the second multi. Then paralleling the output (pass through or inverter power) into ONE AC panel (50amps). Will this work?

Please help!!!

jonathan-contre asked
Johannes Boonstra (Victron Energy Staff) commented ·

5 Answers

Firmware matching for Parallel and three phase VE.Bus systems

"All units in one system must be the same type and firmware version, this includes same size, system voltage, and feature set. The type is indicated by the first four digits of the firmware version number."

Regarding this statement, how often do the first four digits change ?

Assuming the first four digits are related to manufacturing date.. Depending on supply and demand for that product it could be 6 months or 12 months before a different "hard" firmware of the one product is distributed.

I only ask because I am designing a system for a customer who would like to start small and upgrade later. But if he can't parallel the same product because the first four digits don't match then we're in trouble. But if he upgrades with in 6 months it should be okay?

Isaac Shannos asked
Isaac Shannos commented ·

1 Answer

2 x Multiplusses 48/5000 in parallel - trips inverters on mains fail

Units installed March 2020. Worked perfectly for 4 months. Both units now fail (inverters trip) when the mains (AC input) fail. Have isloated the units outputs - not connected to any load. Definately not load related. Used Quick Cionnect to reconfigure as parallel pair. No error codes which can be related to Quick Connect log. I find it strange that both units fail simultaneously - I will appreciate any information to get these units operate again.

bernard-forrer asked

0 Answers


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