Sinclair SWC-03 User Manual page 42

If timer function is on, the set hours will decrease as the unit
operation time increases. In this case, residual hours can be viewed after
entering timer setting page. This timer function will be carried out for only
once and then it will be cancelled automatically.
Note: If this timer function is turned on, when the unit is turned on or
turned off, this timer function will be cancelled automatically.
Fig. 17 Countdown timer off
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