Sensoray 3011S - Manual (Page 26)

Firmware reset
During the firmware update the new firmware image is stored into a new location of the
internal flash memory storage, while the original image is preserved. To revert to the
original firmware press and hold the configuration button through the pin-hole on the
back panel while the power is being applied. Release the button as soon as the indicator
LED lights up. The unit will boot from the original firmware image but the user settings
will be preserved.
In order to reset the user settings follow the same procedure, only hold the
configuration button until the LED starts flashing.
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