Loss of mains detection making generator unuseable

Q&A and troubleshooting
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1

I am having problems getting a generator to be accepted by a system which is normally grid-tied, but requires generator charging during prolonged outages.

The inverter is a multiplus 2 48/8000, with the full installation islanded via the internal relays. Set up as zero export ESS.

Using a transfer switch to switch between grid and generator supplied to the AC in I thought would be ok, but with LOM active, the generator fails the LOM test and is kicked off.

Disabling LOM allows charging (once AC input is changed to “generator” in venus).

I am considering changing the inverter for a quattro, as it has 2 AC inputs - but can anyone tell me if the LOM applies to both inputs or can it be disabled on one?

Or will I really have to go into VEconfig and disable LOM whenever I need to use the generator?

Thanks!

Failing this does anyone have a simple solution?

2

Many things can be found in the generator FAQ

But to summarize, by using an ESS the options are very limited. You could use an external anti-islanding relay like a Ziehl URF on the mains input and then set the gridcode to “Other” and disabled LOM. If your grid supplier allows for that.

Other options would be to use the generator solely to charge the batteries, by powering one or more chargers.

Or switching to a Quattro, which is specifically designed for this. ACin1 would be the generator and ACin2 the mains. You can then still only set a gridcode for the whole unit but enable/disable LOM per input.

3

Yes, LOM is set individually for each input on a Quattro.