No-load losses

No-load losses are the power a device draws just to stay energized, even when it delivers no load. In a transformer, this is mostly core loss, also called iron loss, made up of hysteresis and eddy-current losses in the core steel, plus small dielectric and excitation-current losses. These losses are present whenever the transformer is energized and depend mainly on voltage and frequency, so they stay nearly constant while load losses rise with the square of load current. Total transformer losses are the sum of no-load losses and load losses, and transformer loss tables give no-load figures such as 510 W to 1100 W for a 500 kVA unit, depending on loss class. For inverters, datasheets give the same idea as standby, night or no-load consumption, or as tare loss.

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• sentence 4: support check: partial - Sum of no-load and load losses and the 510–1100 W values are given, but 'depending on loss class' is only implied by the A0–E0 labels; the table doesn't explicitly say loss class.
• sentence 1: review: partial - The passages define no-load loss only for transformers (the power to keep the core energized while not supplying load), so widening it to any device goes beyond them. -->