Quattro isn't syncing with the grid

DIY
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1

I have a 3-phase system with 3x Quattro 48/5000/70-2x100. After a power outage, the inverters went into UPS mode (i.e., they supplied power from the battery as intended). Once the grid power returned, the Victrons no longer switched back to the grid. We put them back into single mode and had them switch on individually. L1 and L2 synchronize perfectly. The third inverter does not. You can hear the relay click, but then it immediately switches to “off.”

The NS log shows “Undervoltage” for every synchronization attempt.

Any ideas as to why this is happening or what can be tested?

The system was running fine for about 4 years now…. until yesterday…

2

If one of the phases is below the minimum connection voltage they will reject the grid until it is within the threshold.
Grid rejection is a symptom of poor grid quality.

3

Hi all, Voltage and Frequency is in the specified range…

4

Not from the inverter’s perspective.
You can always swap inverters around and see if the issue moves.

5

The electrican was here right and checked the system everything is ok.
The Monitor shows green for Voltage and Freq….

So can i find detailed error information anywhere?

An Solaredge Inverter is running on the grid right now without problems.

Now we will take another phase for testing on this inverter, if it connects ok, if not hardware failure?

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6

Best to swap phases or devices around and see if issue stays or moves. Then you know there’s a hardware issue.

1 Like
7

Ok, we changed the phases now. The inverter does not connect, but the two others does on this phase. How do I file a warranty claim?

8

You take it back to the supplier you bought it from or log a support call via the support link on the main victron site.

9

We have now switched all the inverters to the AC-IN-1 input, where they connect. So it seems there is a problem with the AC-IN-2. The system is currently operating as a UPS at a facility—how does the replacement process work in this case? Will a new unit be sent and installed, or will the existing one be repaired and we’ll have to wait for it?

10

Existing one will be sent for testing and repair, in most instances.
They may choose to swap it but that depends on what they find so it isn’t worth guessing.
For a critical system it may be worth keeping a spare unit.