Juraj Nikolov avatar image
Juraj Nikolov asked

Paraller phasing of two MultiplusII 5KVA for one phase system it is possible ???


I have a single phase off grid system on an MPII 5KVA using the SOC generator function to switch via ATS to the distribution network (I don't use it as a generator!!! If the PV is disconnected (SOC) the whole system is connected to the distribution network. "Please don't confuse this with a generator" ). I am satisfied with this solution.
But I would like to increase the 1 phase power from 20A to 40A by parallel wiring and keep the wiring I have (if possible). In the prospect documentation it is written that it is possible to connect up to 6 pieces of MP-II (parallel). Honestly, I'm not quite sure how to connect it :) So maybe you can guide me if I'm doing it right...
Question about connecting two pieces of MPII in parallel (one phase):

a) From MPII (Slave) AC OUT1 I bring the cables to MPII (Master) AC IN, since I do not use the distribution network via victron (we don't have to solve why).
b) Or MPII (Master) AC out I will send the cable to MPII (Slave) AC In - but here I have a feeling that the Master-Slave logic will change :)
How to actually wire it properly???
If I'm not mistaken, I have two options to connect and configure?
1) is a generator where additional MPii are connected from a certain load
2) parallel phasing - this seems like a more reasonable solution to me, but I haven't been able to find out how it works in practice yet.

Regarding the following configuration (ve.config), I found something regarding parallel connection via ve.config. I will document later.

Thanks for advice.

MultiPlus Quattro Inverter Chargerac couplingmulti phase
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1 Answer
wkirby avatar image
wkirby answered ·

In short, it is possible to parallel two of the same units together.
The VE.Bus data cables will ensure that the two units are in phase for parallel operation.
The AC and DC cabling is vital. Make sure the lengths are the same for current sharing to be equal.

I highly suggest that you sign up (for free) on Victron Professional:

Watch the online training videos on Three Phase or Parallel theory and installation.

This is not a task to be taken lightly, if you do not understand everything after the training then I would strongly suggest that you engage a professional to perform the installation for you.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Juraj Nikolov avatar image Juraj Nikolov commented ·
@WKirby thank. I hope I find the answer there ;)
0 Likes 0 ·
Juraj Nikolov avatar image Juraj Nikolov commented ·


OK a watch it, but I still have questions, if I can ask :)

1) ok I will adhere the length of AC and DC. And this cabling for parallel connection it's I think OK, or ?


Because I didn't find how to cable it :) And I didn't to realize it never before :)

2) And I see two potential way how to make it:

a) this parallel - I think in this solution is possible to use AC 1phase generator (or grid)

b) via AC in (as generator) , but then I can't use a generator (it is way if the inverter is not compatible).

c) it is possible also connect the AC IN as AC out ? And this AC IN to feed from generator, or grid ? or AC IN is used only from Master ?

3) I didn't find how I set Master and slave inverter and how it work. If the master or slave inverter get in to the failure (hw reason), whole system get down or should be work on one inverter, but by lower output ?

But many thanks for direction and help ;)

0 Likes 0 ·

Related Resources

Additional resources still need to be added for this topic