Omron HR-500U Instruction Manual page 22

DELETING THE MEMORY AND SETTINGS
Erasing the memory and all settings
Use the following procedure to erase all workout data and user
settings (factory reset):
1. Press and hold the ENTER, UP, and DOWN
buttons at the same time for at least 3 seconds.
2. Select "YES" with the UP or DOWN button.
NOTE:
Select "NO" with the UP or DOWN button to cancel the operation.
3. Press the ENTER button.
The screen display will turn off, indicating that all set values
and measured values have been erased. To use the unit again,
you must turn it on and configure settings. (Refer to "INITIAL
ACTIVATION" and "SETTINGS MODE".)
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