current limit Image

current limit

Does limiting charging current on MPPT also affect load output?

I have a 100/20 SmartSolar MPPT charge controller with a load output that I would like to use to charge a 60Ah lead-acid battery.


Does limiting the charging current to 12A in the app (20% of 60Ah) also affect the load output? Or could I, under adequate sun conditions, get the 12A to the battery and draw additional current from the load output (for instance 2.1A to charge a phone through a cigarette lighter plug) so in that case get to 14.1A?


Thanks!


matt13 asked
matt13 commented ·

1 Answer

AC Current sensor distance from Multiplus

My Multiplus installation will be a significant distance from my DB board and ATS, where my generator is wired for backup supply. The area where my main DB board is installed reaches about 35-40 degrees Celcius in summer (direct afternoon sunlight [in South Africa])

The distance is about 15m.

I would like to be able to start up my generator in certain situations, but need to limit current towards battery charging.

What would be the solution for this?

whjmarais asked
kevgermany answered ·

1 Answer

Multiplus2/Bluesolar limited/throttled solar production

System:

2 x Multiplus ii 48/3000/35-32 in parallel

1 x Bluesolar MPPT 150/70

8 x Trojan T125

18 x Renesola 300w panels 6 strings with 3 panels per string

Running ESS feeding excess to the grid.


I started off with 1 multiplus and 9 panels with average output as per graph.

[image]


I then upgraded with another 9 identical panels. The output was capped at just over 2kw.

[image]


And after adding another multiplus it is now capped at 3,6kw from 10am to 2pm.

[image]


Thinking that the inverter current is derated due to temperature as the internal fans switch on at 09:30 in the mornings already with room temperature between 20-23 degrees C, I have installed 2 120mm ac fans on each inverter and another one on the mppt ducting air into the bottom intakes. Before the mppt was almost hot to the touch, and now cool after installing the fan from 10-4pm. The fans made practically no change to the solar output.


MPPT current at the peak readings is 108V and 33A that is just over 50% capacity. At 3,6kw production the inverter is running at exactly 60% of the rated output. Any suggestions as to why production is limited or capped?

wannibi asked
Paul answered ·

4 Answers

Three phase Multiplus nominal / max power

Hi,

I read some messages with a Multiplus overloaded at lower power than nominal power.
I read documents from Victron with max power at 130% of nominal power (during 30min).

So I am looking for installation feedback to figure out what is the real capabilities.

What is the nominal/maximum power (for how long) you get from your three phase Multiplus system on DC supply ?

Thanks in advance for your feedback.

Gabriel asked
Gabriel edited ·

1 Answer

AC Current Limit when using ESS as a grid parallel system

I have a Multiplus II GX system which is installed with the ESS application. It's connected to the UK grid via a single phase 100A supply, connected to AC IN of the Multiplus.

All loads and an AC coupled solar inverter are also connected to AC IN of the Multiplus.

The Multiplus is able to balance the grid supply close to zero, charging the batteries off of solar and discharging them as required. I also have time of use tariff which enables the Multiplus to charge the batteries over night.

The issue I have is that I run a lot of loads over night in the cheap period of my tariff including a 32A electric car charger. This regularly take my load over 50A.

The Multiplus needlessly regulates its own charger down in this period and on occasion supplements my grid supply from batteries. This is needless and results in me not having a full battery bank at the end of the cheap time-of-use period.

I can't increase the current limit beyond 50A on the Multiplus or seem to disable it. It is not needed in a parallel grid connection as I have it, as far as I can see.

Can somebody advise me as to whether I have missed a setting or if this is something Victron need to consider in a future firmware update. I want to be able to heat my water, charge my car, batter bank, run my dish and clothes washers during my off peak period!


Marcus Fosker asked
shaneyake commented ·

6 Answers

Inverter charging and discharging with AC limit enabled

Hi all,

Some background; Multiplus-II-GX grid tied, supplementing house via 'AC input 1', I am using ESS charging schedule along with limiting the max inverting system is a '48v' (58.8v) liion setup with it's own BMS that does not communicate to the inverter.

With no limit at 3000W which is the rated output the system works absolutely as intended, and when set to 0W it completely stops inverting.

I believe that I have a configuration issue here as this only occurs when I enable the 'Maximum inverter power' option to (for this example) 500W, the inverter seems to be ignoring the 500W limit.

[image]

[image]

*the 99% SOC is wrong since I tried a firmware update, it was correct prior to 30 minutes ago

**I would also note that I use an external current monitor but the 'Grid' has NEVER shown correctly even though it does keep the house at around 10W and charges correctly when solar excess is occurring.

At 500W I then see the inverter switching between charging and discharging, seemingly trying to get to 500W as seen below:

[image]

I'm open to share more for troubleshooting as I've reached my Google-fu ability with fixing this.

Hope someone can shed some light!


***EDIT: possible cause; when the limit is enabled it goes to the max current then scales down. So if the house load is 700W and the limit is 500W it will go to 700W then down to 500W but when the load is 2700W it goes all the way, then starts a bulk charge?? and repeats this behaviour.

gladmac asked
gladmac edited ·

0 Answers

Multiplus ii external current sensor for current limiter

Dear all,

Where can i find the documentation of the external current sensor of the multiplus?

what functions does it has or how it works exactly?

when i set my current limiter to 35A in the multiplus ii and place an external current sensor.

can the multiplus ii draw 45A?

[image]

*yea i know i should change the picture of the multiplus to a multiplus ii :D

marc-heide asked
Richard Weir answered ·

2 Answers

AC Input limit weirdness

System:

Quattro 120v/5000/24v running ESS (custom grid code).

10 Kw LiFe storage

7 Kw genset

Variable shore power options.



When AC input limit is 25A or greater, everything works as expected, with loads running off incoming AC, up to the limit, and any difference coming from batteries, until SOC limit. Perfect.


When it’s anything less than ~25A, it seems, the Quattro loses its mind and basically ignores that setting, or goes bonkers switching back and forth and back again between the battery and whatever the input source —often to the detriment of the input source.


Example 1:

Using a generator, setting the input limit below 25A essentially causes the generator to detect a fault on the line and eventually shutdown —right before constantly oscillating up and down trying to keep up with the inverter.

Initially, I just ignored this issue and wrote it off as a “weird” compatibility issue between an inverter genset and the Quattro. There are copious posts about “syncing” issues with inverter generators and these inverters.


Example 2:

A 20A 120v “mooch docking” option was made available (instead of a generator). This was intended to act as a constant drip of AC, at a very low draw, with the smart Victron inverter in between handling the balance.

Set input limit to 10A.

Utterly ignored. Everything was coming in from the “shore” plug, regardless. But, at least it was stable in its ignoring the limit.


Then, I figured out that SOC was below set-limit, so that made sense. It was essentially running in pass-thru mode. So, I adjusted the SOC limit to well below battery’s current SOC. This should allow it to make up any deficit from the batteries (which had plenty of capacity remaining).


That’s when things got even more weird. Being allowed to actually draw from the battery caused the same ping-pong effect I described in example one above, with the Quattro constantly swinging wildly on input power and battery draw, and then eventually it fully exceed not just the 10A limit I set, but the full 20A limit of the plug, and blew the breaker.


So, I’m confused as to what to expect from that input limit. It seems to be essentially worthless below 25A —even though the UI very clearly lets one set it that low.

And not only that, but it seems to make things considerably worse for the input line, whether that’s a genset or (otherwise stable voltage) input from shore power.

geomz asked
JohnC answered ·

1 Answer

Multiplus/48/3000 connects to Generator but doesn't charge. DVCC or tail current issue?

Hi All,

I'm running an off-grid system using MultiplusII/48/3000 with a Cerebo GX, MPPT/250/100 VE.Can rev2, SmartShunt 500A all connected with VE.Can. My battery setup is 20x 250A 12v Gel batteries in 48v with 3 battery balancers.

On the Multiplus AC input we have a 7.5Kw generator that we've configured to start when GX relay is turned on. We want to use the generator on cloudy days top up the batteries while briefly running our critical load.


When we start the generator and the Multi accepts the input, we see the system taking over 1000W from the gen to supply load and help charge the batteries alongside the MPPT250/100 as we expect. However, after less than 2 minutes, the load on the generator starts to drop in a very controlled fashion. It appears that either Multi or another device is limiting the generator input for charging, even when the MPPT is clearly still in bulk and the batteries need charging. This makes us very nervous about when bad weather will come and we'll be reliant on the generator charging the batteries.


We have not enabled DVCC yet for this install as we're not entirely confident about its impacts with our setup and running these Gel batteries. We also have issues with the Smartshunt's tail current settings not being able to set the % value below 0.5%. Given we're running over 1000Ah storage capacity, a tail current value of 0.5% is still 50A! We'd need either an Amp value or 0.05% to get to a more normal 5-7A tail current setting. I believe this results in our batteries always showing 100% as soon as the MPPT's start charging in the mornings.

We suspect it may be the tail current setting with battery SOC always being at 100%, but we are unsure this is why the Multi is not using the generator for proper sustained charging along with the MPPT. Perhaps because we're not using DVCC and this will help with global control of all the devices working together?

Attached some pictures showing setup and generator on but not charging. When MPPT is on, it give charge to battery. When MPPT is off, generator still doesnt charge.

Gen with MPPT.jpg
Gen without mppt.jpg
Smartshunt settings.jpg
Multiplus settings 2.png
Multiplus settings 3.png
Multiplus settings 4.png
Multiplus settings 5.png
Multiplus settings 6.png
physical setup.jpg

kmr asked
kmr commented ·

1 Answer

Grid feed-in / maximum phase current

Hi

I would like to know, if the grid feed-in setting (watts) is single- or three-phase, when you have three phase grid and only one multiplus in a system? I have a grid meter, Fronius on-grid 3-phase inverter on multi input + Easysolar 2 on phase 1, and together they could blow the phase 1 main fuse if load is low enough and there is enough solar power available. This is for outgoing energy, but the same question applies for consumption:

Is there a way to limit Easysolar/Multiplus charge current via grid meter, to avoid blowing main fuses? (25A main fuse, ATM 16A max grid charging current, but other appliances might be powered while charging and the risk of blowing the mains is real).

I've tried to search the forums and manuals for this info, but haven't found an answer yet, so I would be very thankful for any insight on this matter.

Kari Saaranen asked
Alexandra answered ·

1 Answer

Cannot change Multiplus 24/3000/70-50 Input Current Limit changed in Remote Controls

For the life of me, I can't figure out in VE Connect which value corresponds to changing the input current limit in the remote controls so I can increase this to 70amps on the input current limit.


Help?

[image]

allswell asked
allswell commented ·

2 Answers

Transient current cause Seplos BMS to shutdown

Hi Victron community, I have one question regarding a couple Victron / DIY LFP pack with Seplos BMS.

If it is just to say that Seplos is not in Victron's compatibility list for BMS, you can save your time and are not forced to participate to this thread ;)

I use this BMS (I have 4 of them) and it is working fine, but, as there is a "but", a big one, I discovered that using only 1 battery pack (14kWh / 200A BMS) with a 5kVA Multiplus 2 doen't allow it to start as the transient current is too high for the BMS (fixed values in the BMS are 250A for 30mS, not changeable if you don't want to damage your hardware and loose the warranty).

Is there a known solution to limit the starting current on the Victron side?

Else anyone intending using those BMS in a Victron environement must pay attention to this "detail" and better find another model if they don't intend to have 2 or more battery pack.


jeanmarie asked
klim8skeptic commented ·

0 Answers

How do I set the Input Current Limit to limit both legs of my 120v/240v shore power?

Basically the title. I've searched the forum and found a couple posts asking similar questions with no answers.

MultiPlus II 12v 3000va, a CerboGX, 5kWh lithium, (with a SmartSolar, but I don't think that affects the question) in an RV. I have 50A shore power available at the moment, but I'm often at a place that only has 15A available. I've been able to set the input current limit and use power assist to mimic having access to only 15A, but I noticed the other day that the ICL is only limiting one of the two legs. How do I get it to limit both legs? I get that 15A is single phase, but if I remember correctly from the last time I was limited to 15A (pre-Victron installation), the 50A>15A adapter functionally makes that 15A available to both legs, of course limited to 15A total. So how do I get the input current limit to limit both legs so that the MP draws power from the battery via Power Assist instead of tripping the 15A breaker every 10 seconds? Thanks all!

mattylight asked
mattylight commented ·

1 Answer

Multiplus 24/3000 violates input current limit settings

How do I prevent the MP from exceeding the input current limit settings?

[image]

Stephen Otto asked
derrick thomas commented ·

2 Answers

Multiplus-II AC Input Current Limit -> Per Leg or Total?

I've got a new installation connected to grid power. Does the AC Input Current Limit setting limit power on L1 and L2 individually or does it limit the total amount of power available for L1 and L2 combined?

TIA

jm0278 asked
derrick thomas answered ·

2 Answers

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