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grid parallel

Multiplus II AC IN vs AC out ramp up speed

I have my ESS system on a simple grid parallel setup with all the loads on the AC IN of the Multi, with an ET112 as grid meter. When there is a change on the loads, the ramping up/down of the inverter takes a few seconds to match it, resulting in overshoots of the grid setpoint. Heard someone mentioning on an youtube video that if the loads are instead installed on the AC outputs the ramping up/down is almost instantaneous resulting on much smaller overshoots, but found no info on it. Does anyone know if this is the case?

paulo-m asked
Jason - UK edited ·

1 Answer

ESS scheduled charging issue with high grid load on grid parallel setup (EV Charging / Time of Use Tariff)

Hi,

I have a grid parallel setup with ESS working perfectly, apart from when there is high grid load during a scheduled charging window.

Setup is as follows:

  • Multiplus-II (48/3000-35-32) inverter AC In connected to Grid, no connections to AC outs, with AC coupled PV on input side. CT clamp on meter tail connected to Multiplus-II for grid consumption monitoring.
  • Cerbo GX setup with ESS (With Batterylife Optimisation on) with scheduled charging setup to take advantage on my low rate overnight time of use tariff.
  • Batteries are 3 x Pylontech US2000C

Scheduled charging works fine until my EV charger kicks in (same window) and suddenly grid load is ~9.5kW with charger, baseload and EV 7.2kW charger, the charging then stops and the batteries start to discharge even though this is a scheduled charging window.

Is this expected behaviour? Surely the inverter should realise this is not current following through the inverter itself, just the AC side of the setup?

My idea for a 'quick' fix is to relocate the CT to my distribution board, as my EV charger is supplied from a separate DB directly from a distribution bus before the main DB, however the cables are tricky to access so keen to know if this will work before making access.

Any advice appreciated!

Thanks.

fjj asked
lackland answered ·

3 Answers

Fronius Primo an MP2 ESS Grid resynchronisation

Hi There,


a question is bugging me:


assume the following setup:


MP2 5000 in ESS setting with Fronius Primo 4.6 (with 4.4kwp) on AC1

Fronius is set to MG50

pylontech battery


What happens when the Grid fails ? --> Multi is taking over and is regualting the Primo via Frequency.


So Far so good.


But when the battery is nearly full or full, and the grid is comming back online ?

I think the multi needs to synchronise back to the grid. It goes back to 50 Hz. But what will the primo do ? When the primo output power goes up and the battery is full and the grid is not yet connected via the ess relays ?

Will there be a DC Ripple problem an system shutdown ?


Best Regards


Ralf



rl78 asked
Rob Duthie answered ·

1 Answer

Multiplus 2 GX mit us3000c schaltet nicht auf Netz um

Hallo

Ich habe einen neuen Multiplus 2 GX mit einer Pylontech US3000C.

Anschluss vom Netz an AC-in, Batterie,LAN,CAN und MK3.

Soweit so gut die Batterie wird erkannt und mit allen Details in der Remotekonsole angezeigt.

Die programmierung über VE Config mit dem ESS Assistenten klappte auch.

Aber nun schaltet der MP2 nicht das Netz zu uns sagt das die Batterie schwach ist obwohl SoC 49%

skyone79 asked
lifeingalicia answered ·

1 Answer

Grid connecting isn´t possible

Hi guys!

I´m running the following system: 3 x Multiplus II 48/5000, 1 x Cerbo, 3 x MPPT, 9 x Pylontech US 3000, EM 24 for measuring the grid. The system runs since about 7 months without any problems.

All units on the newest firmware, the cerbo runs on 2.84.

Since yesterday I´ve a problem: allthough the grid is here as all the time, the cerbo shows grid lost and doesn´t reconnect to the grid. I´ve started the system a few times without solving the problem.

My energy supplier has measured the grid and says everything is fine.

So I don´t understand this behaviour. The system tries about every 15 minutes to reconnect to the grid, then the relais in the Multiplus are switching and immediately comes the message: time synchronisation failed or one of the expected units were not found.

Anyone an idea why the Multis don´t switch trough to the grid?

[image]


koro asked

0 Answers

Solar to Grid if not enough

I am moving my solar panels which were used Off grid on my RV until I built my new small house which is now ON the Grid. I am looking for a way to use the Grid if solar is not enough (only 1700W) currently and not blow a fuse. I need to know the settings on the Inverter/Charger and Charge Controller.

Electrically, I understand that I need to move the breakers off the Grid panel to a Critical Load panel, just 4 at this point and replace with a breaker just 30Amp breaker with the Victron Inverter/Charger in between. Do I need other isolation other than the Hot side fuse and I would prefer the transfer to be automatic.

I am not interested at feeding back to the Grid as that will never be the case until I get more panels, etc.

Does anyone have a drawing so I get it right the first time, otherwise I will not have heat, hot water, stove (all propane) and one kitchen lighting circuit if the Critical load output from the victron panel does not work


simple asked
kevgermany answered ·

1 Answer

AC coupled Quattro + Fronius (microgrid) + Huawei inverter

Hi folks,


I have a quattro + fronius microgrid that's not working very well (tried on output of quattro, tried on input... it's limiting the hell out of fronius output), so i'm currently using the fronius smart meter to limit injection to grid (undesirable as I pay for export).

But next week, I will install another 3Kw system with Huawei inverter (this will also be grid-tied and approved by the power co. for export).


Below is the diagram that I though on using. Basically just inserting the 3Kw Huawei inverter between the grid and the smart meter.

After this new installation, I can inject a bit more to grid from the fronius, or victron, as long as anti-islanding is obtained.


PS - my victron is acting up under heavy loads ( i need to warranty is someday...) from battery, so I am forced to user the EV charger directly form Grid or whenever I do have solar enough to discharge from battery less than 2-3kwh, hence the location.


[image]


iromeo asked

0 Answers

multi plus 48/3000 parallel with grid

Hello.

I use a Multi plus 48/3000 inverter which is connected to the grid via the Virtual switch function. The batteries are charged only from MPPT.

The network comes into operation only when the batteries are discharged or when the consumption exceeds the value set by me. AC1 is 16 amps. The network also has 16 amps. The inverter has 13A.

How can I make the inverter work in parallel with the grid, in order to have a higher power? (16 amps + 13 amps).

Thank you

ciprian-dobrescu asked
ciprian-dobrescu commented ·

2 Answers

Problem with two Quattro in parallel. Sometimes instable.

Hello to all,

I have a problem with two Quattro. As soon as they run in parallel on the mains, the two inverters sporadically " oscillate ". They then make a loud humming noise and then switch off very briefly and then on again. Then it goes on again for some time without problems until it starts again.

With only one Quattro, the system works without any problems.

It also works without problems with both Quattro when the grid is switched off (off-grid).

The effect only occurs with parallel operation on the grid.

The AC and DC cabling is symmetrical (identical cables and cross-sections).

The AC and DC currents were measured and are almost identical/symmetrical (+/- 1-2 %).

The Quattro were parameterised with the MK3 via Quick-Configuration (network: Europe, as I live in Spain). Same type and firmware (updatet to newest).

It seems that the Quattro build each other up on the mains and then switch off briefly for safety. For a short time, very high currents (> 100A) flow on the DC side with only a low load.

I have already exchanged master and slave. Without any change. The problem persists.

No error message is displayed on the CCGX.

Can anyone give me tips on how to solve the problem?

Thank you very much!

Greetings from Spain, Thomas


211201 PV Stromlaufplan.pdf

tnt369 asked
tnt369 answered ·

2 Answers

SMA Tri10000 and multiplus inverter

Hi, All

I have a client who already has SMA tri10000 inverter and 7 kWp solar on site. He also have 10 kWh LTO battery and would like to connect with 3 of multi 3kVa inverter. We are in Australia and multi with battery is not allowed to connect to the grid. We are thinking to connecting SMA to multi and grid as back up. The idea is to install a relay on grid side, when battery is low , contactor close and use grid to supply load. When battery is above some value, use solar and battery to supply the load. All solar and battery energy will NOT be allowed to export to grid. and Grid will not charge battery. I am not sure whether we can achieve this as I did not find any info about 0 EXPORT from SMA - victron connection. Thanks

john2019 asked

0 Answers

What happens with two Multiplus in parallel not linked with each other

Background: I have an old Multiplus 48/5000/70 and I would like to increase the available power with a second battery bank

I'd like to know what happens if I connect the output of a Multiplus to an existing grid formed by another Multiplus. Would it be any different if any or both of the Multiplus is a Multiplus II instead. note that in this example the two Multiplus would not be linked together in parallel, it cannot work as this would require a single battery bank.

Take this schema from the MultiGrid datasheet.

[image]

In this schema, Let's replace the MultiGrid by a Multiplus II (as I understand the Multiplus II is an improvement of the MultiGrid). Let's replace the PV inverter by another Multiplus and the PV array by a separate battery bank (that too has solar panels).

What would happen in such a scenario ?

edit: an answer below tells us that it's impossible to connect the output of two Multiplus together without linking them. But then, if the Multiplus is capable of feeding back current to its AC input, the second Multiplus can be connected via its AC input.

If it doesn't work by replacing the PV Inverter by a Multiplus, can I take the PV inverter and plug it to some batteries instead ?

Thank you

mildred asked
shaneyake commented ·

3 Answers

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