Lo sto vedendo anch'io, e prima non erano così frequente, questo è solo ottobre, dal log di un UPS:
2023-10-30 21:22:24 +0100 Power is back. UPS running on mains.
2023-10-30 21:22:22 +0100 Power failure.
2023-10-30 21:22:08 +0100 Power is back. UPS running on mains.
2023-10-30 21:22:06 +0100 Power failure.
2023-10-30 19:42:06 +0100 Power is back. UPS running on mains.
2023-10-30 19:42:04 +0100 Power failure.
2023-10-30 19:08:25 +0100 Power is back. UPS running on mains.
2023-10-30 19:08:23 +0100 Power failure.
2023-10-30 19:07:45 +0100 Power is back. UPS running on mains.
2023-10-30 19:07:43 +0100 Power failure.
2023-10-30 19:06:35 +0100 Power is back. UPS running on mains.
2023-10-30 19:06:33 +0100 Power failure.
2023-10-30 19:06:05 +0100 Power is back. UPS running on mains.
2023-10-30 19:06:03 +0100 Power failure.
2023-10-30 06:02:39 +0100 Power is back. UPS running on mains.
2023-10-30 06:02:37 +0100 Power failure.
2023-10-21 20:00:51 +0200 Power is back. UPS running on mains.
2023-10-21 20:00:49 +0200 Power failure.
2023-10-21 20:00:00 +0200 Power is back. UPS running on mains.
2023-10-21 19:59:58 +0200 Power failure.
2023-10-20 16:20:13 +0200 Power is back. UPS running on mains.
2023-10-20 16:20:11 +0200 Power failure.
2023-10-20 12:10:17 +0200 Power is back. UPS running on mains.
2023-10-20 12:10:15 +0200 Power failure.
2023-10-20 12:03:25 +0200 Power is back. UPS running on mains.
2023-10-20 12:03:23 +0200 Power failure.
2023-10-20 07:27:23 +0200 Power is back. UPS running on mains.
2023-10-20 07:27:21 +0200 Power failure.
2023-10-20 07:27:19 +0200 Power is back. UPS running on mains.
2023-10-20 07:27:18 +0200 Power failure.
2023-10-19 12:14:06 +0200 Power is back. UPS running on mains.
2023-10-19 12:14:04 +0200 Power failure.
2023-10-19 03:45:00 +0200 UPS Self Test completed: Not supported
2023-10-19 03:44:49 +0200 UPS Self Test switch to battery.
2023-10-03 14:54:32 +0200 Power is back. UPS running on mains.
2023-10-03 14:54:32 +0200 Mains returned. No longer on UPS batteries.
2023-10-03 14:54:07 +0200 Running on UPS batteries.
2023-10-03 14:54:01 +0200 Power failure.
2023-10-03 14:54:00 +0200 Power is back. UPS running on mains.
2023-10-03 14:53:58 +0200 Power failure.
2023-10-02 13:47:45 +0200 Power is back. UPS running on mains.
2023-10-02 13:47:45 +0200 Mains returned. No longer on UPS batteries.
2023-10-02 13:47:18 +0200 Running on UPS batteries.
2023-10-02 13:47:12 +0200 Power failure.
E spesso non ci sono condizioni meteo che possano giustificare queste microinterruzioni - che comunque a livello di IPs potrebbero anche essere causate da spike attivano la protezione da sovratensioni. Stranamente in questi due giorni di piogge torrenziali che ha fatto pure partire la pompa di emergenza per tenere il locale caldaia all'asciutto non è successo nulla.
Se è il test di verifica della tensione dovrebbero mettere un apparecchio che fa misure per un certo lasso di tempo - come gestisce le microinterruzioni non lo so. Se invece viene, misura la tensione e va via è probabile che non lo faccia nel momento di una microinterruzione.
Io da un po' proteggo quello che posso con UPS.