Regarding the radiation level modes of ESS-B3011 and ESS-S3011, EXTRA is described as producing less radiation than NORMAL. However, some EUTs do not malfunction in NORMAL but do malfunction in EXTRA. Why does this occur?

Regarding the radiation level modes of ESS-B3011 and ESS-S3011, EXTRA is described as producing less radiation than NORMAL. However, some EUTs do not malfunction in NORMAL but do malfunction in EXTRA. Why does this occur?

This may occur if the charge/discharge capacitor does not discharge sufficiently during application and some charging voltage remains in it.
In EXTRA, the high-voltage power supply is turned OFF (0V) when the relay is OFF, reducing the potential difference from the charge/discharge capacitor and thereby reducing radiated noise.
However, if the capacitor does not discharge during application and charging voltage remains in the charge/discharge capacitor, the potential difference from the high-voltage power supply (OFF, 0V) becomes large in EXTRA, which may increase radiation. In NORMAL, the potential difference from the high-voltage power supply (ON, set voltage) becomes small, which may reduce radiation.