HomeMatic HM-LC-Sw1-SM, HM-LC-Sw4-SM Installations- Und Bedienungsanleitung Seite 52

at the same time when the power returns (after a
power outage or shut-down).
During this time, the channel LEDs flash (like in
teach mode). If the delay time is short, the flashing
may not even be noticeable.
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