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split phase

2 Victron Quattro's in split phase not starting


I have finished installing 2 Quattro's 48/3000/35-50/50 in split phase with 2 each 48V EG4-LL battery in parallel. As soon I'm switching on the batteries I'm getting error on the 2 batteries, "protected (DOC)" discharging over current protection and the Quattro's doesn't start, not even one at the time. I disconnected the DC (+) from one of them and it's working, I done the same with the 2nd one and it works as well. So the system works with only one but not with the 2 Quattro's connected at the same time to the DC Victron distributer. I Don't know if this have to do with my problem, the firmware are not the same on boot, they are the 27xxx one is the 430 and the 2nd is 481. Please help. Thanks Dan

alfa asked
Kevin Windrem commented ·

1 Answer

AC loads for L1 and L2 not same for split phase Multiplus

I have 2 Multiplus 24/3000/70 Inverter Chargers setup in split phase. Why does my AC consumption show much higher on L1 than L2? L1 is always higher output watts than L2.

In the second pic you can see the AC Output for L1 is 136w and L2 is 3w, why is this not balanced between L1 and L2?



bravebear asked

0 Answers

Split Phase 120° with 2 multiplus II on 3X400+N


Here in belgium we are restricted to max 10kw inverters for residential settings. On a three phase system with 3x400+N normally you would use 3 multiplus II's 3000. But in theory you can configure a split phase system with 120° phase angle. So my question is can I use 2x multiplus II 5000 in split phase mode and let the ESS compensate for the usage on phase 3?

Thanks in advance!

siebe-r asked

0 Answers

Split phase feeding power to grid

Trying to replace a dead Schneider with a Victron system. Current wiring has AC IN and AC OUT of the dead inverter connected through a set of 60a breakers into the 200a residential panel (split phase 120/230) and it was set up to feed power to the grid in addition to taking some of the local load. Power source is 48v battery with dc coupled solar charging (non-victron). I understand I can use an autotransformer to convert a single 120vac or 230vac inverter into split 120/230 L1/N/L2 as needed to connect to the existing breakers/wiring. But I need to confirm a) that Victron inverters can be used to feed power to the grid (nothing to do with grid-tie from solar on AC OUT), b) what the wiring should be for this -- i.e. use the same set of breakers that connect AC IN & OUT, or do I only need to connect the multiplus/quattro AC IN to the grid and done.

So in essence, does the multiplus or quattro inverters have the ability to feed power synchronously to a grid over the AC IN connection -- will it work if I feed the inverter 48v DC and have it generate power to the grid over the AC IN connection only, or does AC OUT have to be tied to the grid in some way (which seems dangerous, and not sure why the Schneider was wired that way).

I understand that I will need to set up the inverter with ESS helpers for it to successfully feed power to the grid and take up some of the local load without having a 100a subpanel to run the loads through (I'm not going to rewire his panel). I'm just needing confirmation on selecting the correct inverter, and how to wire it, and confirmation that this is even possible. I'm preferring to use a single inverter and autotransformer rather than two inverter across the split due to cost, but if there are reasons to avoid the autotransformer for this situation let me know.

stgnet asked
silverfox answered ·

1 Answer

Multiplus II 2x120 generator compatibility.

What is the condition that the Multiplus II 2x120 uses to determine its power flow as described in the Data sheet? Or whether the AC input is 120v or 120v/240v split phase?


In the case of the Multiplus II 2x120, when you connect the inverter in-between the automatic transfer switch and the RV panel the 120v/240v input connection works as intended and a 120v input connection also works as intended. Unfortunately it seems that the Multiplus does not pass through both lines from industry standard generators.


I believe the problem is that a lot of RV and off grid generators only output 120v. Most of them such as the Cummings Onan- 5.5HGJAB-6755L which is rated for 5500watts or 45+amps has two outputs. Each is 120v and outputs about 23amps. In most cases it is not possible to combine L1 and L2 out of the generator as the two lines are out of phase, not 180° out which would give you 240v but 120°. Meaning you can't combine the 2 lines to get the full 5500watts or 45+amps single phase to the Multiplus. Probably a cost savings thing on the part of the generator manufacturer as they can use the same components across multiple generator configurations. Either way this is common place in the industry here in the US.

So my question is, can the Multiplus II 2x120 be configured to detect this power type and passthrough both legs? If the Multiplus is actually detecting the phase and not just 240volts then there should be reason to believe Victron could remedy this with a firmware update. Correct? Also, if the voltage between L1 and L2 is 208v would that be an easier setting than the phase detection?

exmoso asked
sac-rv answered ·

3 Answers

Parallel Quattros split phase ground relay setting

I have an off-grid system (in US) using (2) Quattros (48/5000/70-100/100 120V) configured for split phase parallel operation. Hence, each Quattro is providing a 120V leg which creates a 240V system.

My question concerns the NEC (National Electric Code) requirement for bonding the ground and neutral. NEC requires the ground and neutral to be bonded at the "service entrance" and that this bonding should only be done in 1 place. Each Quattro contains a relay that bonds the ground and neutral by default. If both Quattros are configured to enable the relay (i.e. the "Ground relay" box is checked) this would seem to bond the ground and neutral in 2 places. Should I enable the Ground Relay on both Quattro's or only on 1 Quattro?

tbratten asked
pigwet answered ·

2 Answers

MultiPlus-II 12/3000/120-50 120 - AC input current limit - split phase

When using input current limiting with the Multiplus-II, is the current rating for 1 leg, or both on split phase. For example, if I have a 50 amp input split phase input, do I select 50, or 100.

phil-garver asked

0 Answers

Can two 100A autotransformers be connected in parallel for a 200A split phase output?

Hi VE Experts,
Can two 100A autotransformers be connected in parallel for a 200A split phase output? The system will have two Quattro 15000 240V units. This is for a 240/120V, 50Hz system so we cannot use two 120V Quatto units in parallel as the 120V is only for 60Hz output.



lalith asked
satiagraha answered ·

2 Answers

Autotransformer voltage outputs are different

I am having an issue with the Autotransformer output voltages - 114V on L1 and 120V on L2 (with no load)

120V current is supplied by a Quattro 48V / 10000 / 140-100/100 to the 100A Autotransformer. I'm using the AT to provide a split-phase 120/240v supply to the 50A main break panel in my RV

I have wired the AT connections according to the diagram #3 shown on the system schematics page from the Victron website: (https://www.victronenergy.com/upload/documents/AT-3-split-phase-120V-to-120-240V-with-Quattro-120V.pdf)

The Ground Relay in the Quattro is set to ON and is correctly grounding the Neutral to earth.

Here are the voltages I read at the terminals:


The problem I have with this is that the voltage on L1 decreases a lot with load, and when occurs equipment will pull more current to compensate for the lower voltage.

Here is a pic of my RV control panel, showing the disparity in voltage between L1 and L2. Even though there are 2 air conditioners on Line2 it has only dropped 2 volts - Line1 dropped from 114v to 105v. This can't be good.


Questions: 1) - Is this method of wiring correct, and 2) what is causing the voltage discrepancy?


Aug-31: Editing this in an attempt to make the question visible again. I'm thinking of sending this AutoTransformer back to Victron as it is not performing to expectations. I have seen voltages as low as 96 volts on L1, at which point my UPS shuts down my computer, and various other circuits shut down. Not happy...

I'd appreciate a comment from anyone who has had experience with an AutoTransformer.


Pete MacLachlan asked
wolf commented ·

5 Answers

Split phase requirement for 240 volt HVAC system

Hello everyone! I'm new here and really enjoy the extensive knowledge Victron puts out to its customer base!

So, here is my situation. I have the need for 240v split phase (SP) on my RV due to the installation of a 240v inverted mini split HVAC system. I've heard that there was a method to get one Multi (L1) to passthrough/charge and another Multi (L2) to invert from batteries to make 120/240 SP when incoming power is only 120v single (Obviously not as efficient but with solar and many kWh on hand it could work). I've also seen Victron's recommendation to use a 240v inverter coupled with an autotransformer to make 120/240 SP but that would be problematic when the incoming power is only 120v because I would need an autotransformer to make 240v. That's two autotransformers! Not to mention, I already installed two 120/3000/70 Multis configured in SP.

Now to the question, using the method above where you have one Multiplus passthrough/charge L1 and the other invert for L2, how do you program it?

Or another option would be to utilize a skylla-ip65 120/240 charger for when incoming power is not ideal?

Hope this makes sense. Thanks!

fulltarr asked
mike-g answered ·

1 Answer

Multi+ Duplicating Watts readings on a 230v Split Phase with Autotransformer

Hi Victron,

I live in Central America where we use the US Split phase grid system, I have a ESS system with:

- 1ea Multiplus 48/5K/ 230v

- 48v Lifepo4 Bank 450ah

- SmartSolar MPPT 250/100 rev2

- AutoTransformer 32amps

Note: the system does not feed to the grid.

I have setup my system as per Auto-transformer manual advice for Split Phase systems as below:


I have noticed from the beginning of my setup a drastic Watts measure change when Grid goes out and I already read your article here https://www.victronenergy.com/live/ccgx:ccgx_faq including the Q6.

But My case is in my opinion more drastic reading difference.

This is a normal Watts reading with Grid power:

- My home consumption says: 1016W

- Battery charge current: 48.6Amps (2452W)


Right after I open or disconnect the Grid:

- Home Power consumption: 480W (Half reading). I confirm No changes in the Real home Load equipment.

- Battery Charge Current: 58.8A (2971W) Yes the MPPT generation increases in that moment 100W but that does not justify the 500W (10Amps) Battery Charge increment. Looks like the increment in charging is due to the decrease in Loads need by the Multi+


The behavior is telling me that for some reason having a 230V Multi connected to 2 Live power lines (L1=120v + L2=120v), the Multi is duplicating the reading in the ACin/ACout side and direct affecting the battery charge performance. Since this 230v Multi+ is designed to connect L1=230v + Neutral. I think this Multi+ is not properly reading 2 live phases L1 + L2 correctly, instead it is duplicating the reading.

I have done other testing with a 3rd party watts reading and the reading is half lower than Multiplus AC Loads reading and that make me think my suspicious is correct. Can Victron staff please confirm my situation here?

I know that an option here is to get the Carlo Gavazzi meter for better reading, but I will like to ask if Victron can do a Firmware adjustment for customers that use their 230v Multis in US market before expending more money.

@mvader (Victron Energy)

Thanks a lot

Yusef Neblett asked
pganguet commented ·

7 Answers

Split phase with two 120v Quattros and 5500 onan genset 30 amp each leg in an Rv configuration

I have two quattros I am going to setup as primary and Secondary/slave. I believe my 5500 watt onan is split phase 180 degrees out for 120/240.

Do I need a transfer switch if the genset is connected to ac-1 input on both quattros?

I would like to wire the quattros with each leg from genset to each Quattro along with each leg from shore power to each Quattro.

just want to make sure the transfer switches in the quattros can handle the transfer between shore and genset without an external transfer switch…

thx for any input

Geoffrey Schwark asked
arstegmeier commented ·

2 Answers

Quattro's in Split Phase connected to 120v input

Below are the details of my installation:

Product Quattro 48/5000/70-2x100 120V

Firmware version 424

Product id 2753

VE.Bus connection VE.Bus

Hardware configuration Two units configured as 120v/240v split-phase

I went with this configuration for my Motorhome RV based on the advice of Victron that when connected to 30 amp RV service (Which is only 120v) the inverters would support this by having only the master inverter connect to the 120v source and the secondary inverter would remain in "inverter only" mode. I tested this out on some 120v outlets and found that it worked fine at the time. 50 amp service is no problem because 50 amp RV service is 240v split phase which allows both inverters to connect to the AC source.

However I recently tried to plug into a 120v outlet because my motorhome is in the shop (No sun for solar charging) and my batteries were getting low and desperately needed to be charged. I plugged into a 120v outlet at the shop and the lights on both inverters just flashed back and forth at me. No warnings or errors were displayed on my Color Control GX. I didn't have my laptop with me to connect directly to the inverters to see if that offered any more insight.

I haven't made any configuration changes to my knowledge that would affect the inverters phase split configuration, so I'm a little puzzled about what the issue might be. It's been so long since I set this up I don't even remember where in the configuration you can configure it to allow only a single inverter to connect to a 120v source when in a 240v split phase configuration.

The motorhome is still in the shop so I'm hoping I can get some ideas of exactly where to look to identify/fix before I go back and try again to get the batteries charged.

irwinr asked
arstegmeier answered ·

1 Answer

Multiplus GFCI Issue

Ok, so I just swapped out my magnum inverter for 2x24v/3kW/70a multipluses set in split phase with the legacy apps. I'm hooked up to a 50a service. I check all the voltages everywhere, all good. Proper 120's and 240's where they should be, starting at the shore power in through the inverters and all the way back to the house breaker panel. Turn the breakers on, GFCI is yellow, and won't reset. I'm not hooked up to 12 volt with the inverter just yet. That's powered by a single 12v hooked up to a separate battery charger from an external 110 outlet. I did some research and checked my water heater element because sometimes coincidence happens, but no problem with that. Not sure what to do now.


erb9784 asked
russ edited ·

1 Answer

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