@classmethod
def _get_sensors_power(cls, chassis):
    """Get power supply sensors reading.

        :param chassis: Redfish `chassis` object
        :returns: returns a dict of sensor data.
        """
    sensors = {}
    for power in chassis.power.power_supplies:
        sensor = cls._sensor2dict(power, 'power_capacity_watts',
            'line_input_voltage', 'last_power_output_watts', 'serial_number')
        sensor.update(cls._sensor2dict(power.status, 'state', 'health'))
        sensor.update(cls._sensor2dict(power.input_ranges,
            'minimum_voltage', 'maximum_voltage', 'minimum_frequency_hz',
            'maximum_frequency_hz', 'output_wattage'))
        unique_name = '%s:%s@%s' % (power.identity, chassis.power.identity,
            chassis.identity)
        sensors[unique_name] = sensor
    return sensors
