High limit setting for a special sensor.

        For LS-10/LS-20 base units this is the alarm high limit.
        For LS-30 base units, this is either alarm OR control high limit,
        as indicated by special_status ControlAlarm bit flag.

def high_limit(self) -> Optional[Union[int, float]]:
        """
        High limit setting for a special sensor.

        For LS-10/LS-20 base units this is the alarm high limit.
        For LS-30 base units, this is either alarm OR control high limit,
        as indicated by special_status ControlAlarm bit flag.
        """
        return self._get_field_value(SpecialDevice.PROP_HIGH_LIMIT)