@david08 The battery is inserted on the bottom part of the core, the white part in front of the DIN-rail release lever. You can try to remove and reinsert the battery. Is is a mechanical bug so a real bug from the old day's 😉 btw: There is also a SW big causing the GUI to show a stalled 1-1-1970 and once that one is solved your clock will just stop when powerred down making the problem smaller
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