'Convert nad volume range (0-200) to internal volume range.
Takes into account configured min and max volume.'

def nad_vol_to_internal_vol(self, nad_volume):

    if (nad_volume < self._min_vol):
        volume_internal = 0.0
    if (nad_volume > self._max_vol):
        volume_internal = 1.0
    else:
        volume_internal = ((nad_volume - self._min_vol) / (self._max_vol - self._min_vol))
    return volume_internal
