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Multiplus-II: Input current limit ignored after heat warning

Hi all. My Multiplus-II (24/3000/70-32, fw v.487) is acting strangely today. Been fine-tuning my setup since august last year and everything have been working perfectly. I am using Venus OS large with node-red to control most functions of the setup, which includes two shunts (one to measure battery current and one to measure PV current), several off-brand MPPT's, and a big battery bank of 32 x 75Ah AGM batteries.

Today i received a warning e-mail from my node-red system about a temp warning. I went to the unit and checked, it was warm, very sunny day which means several dump loads have been running very long with a total of 2 kW, not surprising that it got hot, but after removing the lower grill to ease air flow the warning went away. My idea was next to help it a bit by enabling the grid and power assist on 3.5 A to take some of the load off the inverter for a while. I have used power assist very much and it has always kept the limit, but to my surprise, even though I double checked the setting in the console, when I stopped ignoring AC in, it went up to 8 A power assisting, then switched to passthru not inverting at all, then back to power assisting 7-8 A and to passthru and flipping between the two constantly. Wut?!, I ignored AC in which had it inverting the whole load perfectly fine.

In the evening when one dump load had turned off and the load became lower (around 1500W), I tested the power assist function again. It is set at 3.5A still and it started assisting with 8A, then after a few seconds started going down and finally settled at the level I am used to seeing. Now it goes to the "right" limit straight away when stopping ignoring AC in, working as it has always been before.

Anybody have an idea what caused this? I merely want to understand it, I believe it is a good idea to install an extra fan to cope with these cloud-free sunny days, but why the power assist function would become non-functional because of a bit of extra heat is beyond me. Note that it never went into temp alarm, only temp warning...



mrhappy asked
mrhappy edited ·

0 Answers

Add PowerAssist spec to the data sheets and manuals for all inverter/chargers

I have changed the title of this question. I believe the issue is the documentation but need this verified by Victron engineers.

Looking at the 120 volt Quatro manual, it states the the maximum power assist is 5 KVA or 42 amps. The 230 volt Quatro manual states different power assist maximums for each model.

Obviously, 5 KVA of assist on the 3000 VA Quatro is not correct and should be 3 KVA.

Is the same true for the 10000 VA Quatro: max PowerAssist of 82 amps?

PowerAssist is usually described as the AC input current limit plus the inverter's maximum output. So for a 10000 VA Quatro set for maximum input current that would be 184 amps. Is this the correct number?

I can see there may be other limits in the design that might reduce this such as circuit board traces or output connectors.

Interestingly, the maximum output current or power is not specified on any models I looked at.

AC 2 out has a limit of 100A due to the relay in that path but AC 1 has no relay

Is the AC-out-1 maximum current always the sum of the input current and the maximum continuous power divided by the system AC voltage?

OR is there some limit in the circuitry that limits the output current to a lower value?

I have found other inconsistencies in the manuals in the AC-out-1 section where the output breaker and wire sizing is discussed. For example, the manual for the 120 volt Multiplus 3000 VA unit calculates the maximum output current based on a 230 volt AC voltage not 120 volts.

I would like to see a "Maximum AC 1 output current" and "Maximum AC 2 output current" specs added to the data sheet and anywhere else the specs are tabulated. I would also suggest Victron update the AC-out-1 discussion to make it more clear what these values will be for each model.

Also, the manuals for all 120 volt models should be reviewed to make sure a 120 volt AC system voltage, not 230 volts is mentioned everywhere.

Kevin Windrem asked
Kevin Windrem edited ·

1 Answer

easysolar 12/1600/70-16 MPPT handling big loads


actually I've got a MP2 48/5000 and 14KWh battery system working in my house so some ideas of what might work do already exist... but:

I've been asked to build a smaller/cheaper solution for a friend and so I found the easysolar 12/1600/70 -16 and this would do for 80% of the usecases... but what happens if a load greater than 1300W is connected?

The AC1 will be connected via 16A fuse to (normal) grid, Batteries charged via MPPTs...

I'd like the inverter to handle the smaller loads in order to keep the grid-cost low.

When a big load comes, does the inverter deliver 1300W and rest comes from grid or will system go to overload?

And is it possible to connect the easysolar 12/1600.... (via GX) to VRM Portal for better remote control / Service?

Thanks for any information about the load handling / VRM connect.



jbrex asked
jbrex edited ·

2 Answers

No current or power limit in scheduled charge mode

Does anyone know how to explain the setting of current or power in programmed charging mode ? Apparently there is no current or power limit.

nostromo asked
nostromo commented ·

1 Answer

How to switch power assist on an off via node-red?

For some years I have controled my Multiplus (I not II) with a raspberry pi via two DAC and the assistants for "Charge current control" and "Input current limit control".

Since now an extension of the solar plant took place, I wanted to use a Cerbo GX instead of the Raspberry Pi and do without the DA converters but regulate this purely via software. More precisely, by means of Node-red on the Cerbo GX.

But unfortunately I miss the possibility to regulate the charging current (of the Multiplus charger) and also the regulation of the power assist mode does not behave as expected.

I have installed the "large" Firmware (V2.82) on the Cerbo GX and I have enabled node-red and I'm using the node-red-contrib-victron node.
Devices are: Cerbo GX, Multiplus 24/3000, BMV-700, MPPT250/60, MPPT 75/15.

The AC charger node reports "There are no ac charger services available. Please check that a ac charger is connected or try a different node." The "multi control" node has no input for charger settings too.

Question: How can I control the Multiplus charge limit?

The input current limit can be read and writen by "Multiplus Input 1 AC current limit" in and out node but the behaviour is a little bit strange.

From 3 to 16 A current limit, all works as expected. i.e. when I set it to 5 and read it back afterwards, i got 5.
But when I set it to '0' , i got '3' when i read it back, but the Multiplus stops Power Assist mode (as expected). Is this (set to 0 to disable and set to >=3 to enable) the only way to enable/disable power assist?



erichabg asked

0 Answers

Power Assist Boost Factor and overloading MutiPlus

I have a 12/3000/120 MultiPlus and I'm trying to understand some Overload issues that I'm experiencing and wondering if the Boost Factor is potentially causing the issue.

Setup is as follows:
Input Limit: 30A
Power Assist: Enabled
Boost Factor: 2.0
UPS: Disabled
Input Power: 4500W Inverter Generator (3800W running)

I've noticed when a large load comes online that the MP will overload and disconnect. I also get an error from my EMS that the voltage has gone "out of spec" (sadly it doesn't tell me which way). What is interesting is that the load is under the 30A input limit and can easily be handled by the generator alone. I'm wondering if the MultiPlus is "preparing" to power assist approximately 7200W (Boost Factor * Input Limit) and causing the overload itself?

If I set the MP to "Charger Only" the Generator can handle these loads just fine. So it seems to be something specific to Power Assist causing the issue. I do plan on turning down the Input Current and running this same test to see if Power Assist successfully assists without disconnecting but I haven't ran this test yet.

Should I lower the Boost Factor down to 1 (or maybe even lower) to stay within the 3000W that the MP can provide? Is there anyway to configure this so that it is not reliant on the input limit? For instance if I'm connected to 15A power I would want a higher boost factor.

Thank you!

Jared Wellman asked
Paul B edited ·

3 Answers

Powerassist in ESS system development

In an ESS system, the powerassist function is disabled by the ESS assistant.

In Belgium the government is going to charge a tax based on the peak power, besides the existing taxes on the amount of imported energy.

This will make the powerassist function of the Multiplus II or easysolar important.

Now we are dependent on integrators to add the powerassist software on a raspberry pi-based module that adds this function to the ESS.

I find it disappointing that Victron is not willing to integrate this function in the ESS assistant.

Is there really nobody in this community that is able to make this work? I am willing to pay a fee for that...

I have a 9kwh battery pack that is set on min SOC of 25%, to be able to deliver backup power when necessary, like an outage of the grid, or the grid voltage raising above the max allowed grid parameter, making the inverters disconnect from the grid.

But there are 2 situations I can think of, in which I want a deeper discharge of the battery.

  1. Powerassist: When the AC input grid power of the house exceeds 4KW, the battery should assist the grid with extra power, so that the input gridpower stays below 4kW. After the power demand in the house gets lower again, the battery may charge back to 25% SOC with low charging gridpower. By the way, Charging the battery with grid power must always keep the total import ac power below 4kW, which is not the case now when setting a higher SOC for instance... A button in the ESS control with a boost charge power would be handy though, when you want to charge the battery asap.
  2. Weather forecast-based deeper discharge: Nothing to do with powerassist. But the battery may discharge deeper in the evening, when the next day a lot of sun is predicted.

maartenvt asked
shaneyake answered ·

3 Answers

Multiplus goes into Passthru when AC-IN overloads


I've a system containing 2 Multiplus II 5000, a couple of MPPT, Cerbo GX and Pylontech batteries.

The system is configured as Single Phase parallel System and all load is connected to AC1 out of the Multiplusses.

PowerAssist is active and also a AC Input Limit of 30A is configured through VictronConnect (with MK3 Adapter).

ESS Assistant is loaded onto both Multiplus.

ESS Mode is configured without battery life with a minimum SoC of 20% in the Cerbo.

Every device updated to the newest Firmware.

When the SoC goes down to 20% the Multiplusses start using energy from Grid. They are in Bulk mode.

That's what I expected.


When the AC Load is higher than 30A the Multiplusses go into Passthru mode.

This is what I don't expect.

What I would like instead:

When the AC load is higher than 30A the Multiplusses should use 30A from AC-in and use the rest from the Battery. When the load is going back under 30A the Multiplusses should fill up the batteries back to 20%.

klandos asked
klandos commented ·

6 Answers

Victron Quattro Power assist configuration problem ?

Hello guys,

I'm living on my sailboat, equipped with a Victron Quattro 12V/220V/3000W and a marine Genset. I'm actually trying to find a way to start my diving compressor, which is a 220V single phase motor 2.2kw, his starting current peak is about 45A.

My genset is a small model, and himself He's not able to provide enough to compensate the Starting peak current demand. So i connect the genset with the Quattro and in theory the genset power + the power assist should be enough to start this diving compressor. But it's not working, i first believe it's because my genset is really to small, but in fact not. See below another test i did and please if you have any suggestion don't hesitate to answer.

When i connect this diving compressor directly to the 220V/16A outlet of the harbor, the diving compressor start and run perfectly.

When i connect this 220V/16A outlet to my "AC in" of the Quattro and the diving compressor is connected to the "AC out", the diving compressor is not able to start! If I'm right, the Diving compressor should be able to start as the Harbor outlet is able to do it, and at least if a little Amps is required for the starting peak, the Quattro should be providing it and the total of this both current should allow the start of the diving compressor. But it's not doing it, I can just hear the Diving compressor motor "growling" but not more!

Do you know if there is any parameter(s)that i should adjust in the Quattro, to allow the full Shore outlet going into the AC out, or if there is a "protection timer" to adjust or something like that ?

Because actually i don't understand if the Quattro is absorbing power of the outlet shore and from that the AC out is not strong enough to start my compressor. Or if the Quattro is stopping the current by the configuration of a thermical protection, timer protection or any "protection" that limit the AC out !

Thank you very much for all the suggestions and ideas that you can offer.

Best regards.


laurent74 asked
laurent74 answered ·

3 Answers

Maximum AC output power with Powerassist on MultiPlus Compact 12/1600/70-16

Is the maximum AC output power of the MultiPlus Compact 12/1600/70-16 3600W (16A@230V) or is it possible to reach higher values with Powerassist?

If I use 16A@230V from the grid via the transfer switch and additional 7A@230V (1600W) from the inverter via Powerassist?

Thanks and best regards,


peewag asked
Matthias Lange - DE answered ·

1 Answer

Multiplus powerassist wrong or broken !

6kW generator is correctly wired as the pass through, through the Multiplus to my panel. When starting AC loads with 20amps , my battery monitor shows high power consumption from the batteries - but after approx. 5/6 seconds it turns to ˋnormal´ (the 20amps-load works fine and the batteries will be charged as usual.)

What can I do to avoid this high loads taking from the batteries for this short time ?

syvalentin asked
klim8skeptic answered ·

7 Answers

Multiplus 12|3000|120 AC-Out-1 wire size

Multiplus 12|3000|120 AC-Out-1: 75A possible. AWG 6 recommended.

AC-In says to use three-wire cable, AWG 6 gauge. Rated for 50A.

I've seen 6/3 cable say 55A per conductor, so is 6/3 cable sufficient for AC-Out-1? Or use three AWG 6 wires, or a lower gauge like 4/3?


hydroplosion asked
hydroplosion commented ·

3 Answers

Voltage correction

Hi There, i would like to ask if the power assist or any other relative function or setup on a multiplus 2 can correct grid problems like voltage drop . I have a pv system connected to battery and grid available but the grid characteristics are bad from time to time and cable lengths to long ( replacing the m is not an option), i was wondering when in power assist if the output voltage of the multiplus can be corrected dynamically or it synchronises with the grid?

Or if there is any other way to use my system as a rectifier

Thank you

dim-avlo asked
Matthias Lange - DE answered ·

1 Answer

Easy Solar II - Power assist - required current sensors

ES II - does it need Smart shunt on a battery side and optional "current sensor" on AC input side to correctly perform Power assist function when using a genset?

All i can find in the ES II manual is: "3.1.8. PowerAssist – Extended use of generator or shore current
This feature takes the principle of PowerControl to a further dimension allowing the product to supplement the capacity of the
alternative source. Where peak power is often required only for a limited period, the product will make sure that insufficient AC
mains or generator power is immediately compensated for by power from the battery. When the load reduces, the spare power is used to recharge the battery.

jj-o-jj asked
Matthias Lange - DE answered ·

5 Answers

MultiPlus 12/3000/120-16 230V power assist

I have upgraded to a Multiplus 12/3000/120-16 230V from a 1600. Unfortunately I have not been able to get the power assist function to work on new multiplus. I have set the input current limit to 3A (manual indicates minimum is 2.3A), when I increase load above this it drop AC input and uses 100% inverter.

Boost factor set at 2, but have also tried at 1 on advice from supplier. I have also tried switching dynamic limiter and UPS functions on/off, but not change it still changes over to 100% inverter on increased load (~1500W).



jibery asked
ludo answered ·

4 Answers


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