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by masklinn 1092 days ago
Surely it’s current draw? Wouldn’t the printer always operate at line voltage?
2 comments

Depending on your supply (for instance in an old house), the printer current consumption can cause a voltage drop on nearby circuits, and this voltage drop can in turn trigger the UPS.
Yes. The voltage alarm in this case would be the voltage dipping too low (voltage sag) due to high current.