AC Ignore Triggering Grid Lost

DIY
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1

It seems that “something” has changed … I used to be able to Enable shore power monitoring whilst the Multiplus was in AC Ignore mode. I recently reconnected to shore power and switched from Sustain to AC Ignore. Enabling “monitor for shore disconnect” now triggers the Grid Lost alarm consistently. Shore power is connected and the Multiplus shows AC voltage.

2

Just to be sure it wasn’t UPS function being ticked by default I turned that off.

Problem remains

3

Turning off the VS and enabling shore power monitoring and everything works as expected

Turn on the VS and Cerbo interprets AC Ignore as Grid lost

Is this a bug in the latest Cerbo GX firmware/OS?

4

Have you got “monitor for grid lost” enabled in the cerbo settings?
On the latest code if it is enabled, there is mains power and the system is forced to invert only (ignore ac) it does not raise a grid loss alarm.
That only happens if there is no AC present.

5

If I turn that on in the Cerbo then I get a “Grid Lost” alarm if the Ignore AC VS is active

6

Try the beta and see if it changes, you can roll back to production afterwards.

7

OK will do

8

OK - installed the V3.60 beta, enabled monitor for shore disconnection (took me a moment to find it in the posh new menu structure), after about 3 mins I get a Grid Lost alarm

9
2025-05-09 14:04:35 260.2 Inverting Ignored Inverting Grid ok
2025-05-09 14:04:36 260.2 Inverting Ignored Inverting Grid ok
2025-05-09 14:05:33 261 Inverting Ignored Inverting Grid ok
2025-05-09 14:06:33 260.2 Inverting Ignored Inverting Grid ok
2025-05-09 14:07:27 260.2 Inverting Ignored Inverting Grid lost
2025-05-09 14:07:33 260.2 Inverting Ignored Inverting Grid lost
2025-05-09 14:08:33 260.2 Inverting Ignored Inverting Grid lost
2025-05-09 14:09:33 259.3 Inverting Ignored Inverting Grid lost
2025-05-09 14:10:33 257.6 Inverting Ignored Inverting Grid lost
2025-05-09 14:11:33 261 Inverting Ignored Inverting Grid lost
2025-05-09 14:12:34 259.3 Inverting Ignored Inverting Grid lost