class Tinkerforge::BrickletEnergyMonitor

Measures Voltage, Current, Energy, Real/Apparent/Reactive Power, Power Factor and Frequency

Constants

CALLBACK_ENERGY_DATA

This callback is triggered periodically according to the configuration set by BrickletEnergyMonitor#set_energy_data_callback_configuration.

The parameters are the same as BrickletEnergyMonitor#get_energy_data.

Public Class Methods

new(uid, ipcon) click to toggle source

Creates an object with the unique device ID uid and adds it to the IP Connection ipcon.

Calls superclass method
# File lib/tinkerforge/bricklet_energy_monitor.rb, line 65
def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 0]

  @response_expected[FUNCTION_GET_ENERGY_DATA] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_RESET_ENERGY] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_WAVEFORM_LOW_LEVEL] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_TRANSFORMER_STATUS] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_TRANSFORMER_CALIBRATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_TRANSFORMER_CALIBRATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_CALIBRATE_OFFSET] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_SET_ENERGY_DATA_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ENERGY_DATA_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_SPITFP_ERROR_COUNT] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_BOOTLOADER_MODE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_BOOTLOADER_MODE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_WRITE_FIRMWARE_POINTER] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_WRITE_FIRMWARE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_STATUS_LED_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_STATUS_LED_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_CHIP_TEMPERATURE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_RESET] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_WRITE_UID] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_READ_UID] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_ENERGY_DATA] = [36, 'l l l l l l S S']

  @ipcon.add_device self
end

Public Instance Methods

calibrate_offset() click to toggle source

Calling this function will start an offset calibration. The offset calibration will integrate the voltage and current waveform over a longer time period to find the 0 transition point in the sine wave.

The Bricklet comes with a factory-calibrated offset value, you should not have to call this function.

If you want to re-calibrate the offset we recommend that you connect a load that has a smooth sinusoidal voltage and current waveform. Alternatively you can also short both inputs.

The calibration is saved in non-volatile memory, you only have to set it once.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 190
def calibrate_offset
  check_validity

  send_request FUNCTION_CALIBRATE_OFFSET, [], '', 8, ''
end
get_bootloader_mode() click to toggle source

Returns the current bootloader mode, see BrickletEnergyMonitor#set_bootloader_mode.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 252
def get_bootloader_mode
  check_validity

  send_request FUNCTION_GET_BOOTLOADER_MODE, [], '', 9, 'C'
end
get_chip_temperature() click to toggle source

Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 310
def get_chip_temperature
  check_validity

  send_request FUNCTION_GET_CHIP_TEMPERATURE, [], '', 10, 's'
end
get_energy_data() click to toggle source

Returns all of the measurements that are done by the Energy Monitor Bricklet.

  • Voltage RMS

  • Current RMS

  • Energy (integrated over time)

  • Real Power

  • Apparent Power

  • Reactive Power

  • Power Factor

  • Frequency (AC Frequency of the mains voltage)

The frequency is recalculated every 6 seconds.

All other values are integrated over 10 zero-crossings of the voltage sine wave. With a standard AC mains voltage frequency of 50Hz this results in a 5 measurements per second (or an integration time of 200ms per measurement).

If no voltage transformer is connected, the Bricklet will use the current waveform to calculate the frequency and it will use an integration time of 10 zero-crossings of the current waveform.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 117
def get_energy_data
  check_validity

  send_request FUNCTION_GET_ENERGY_DATA, [], '', 36, 'l l l l l l S S'
end
get_energy_data_callback_configuration() click to toggle source

Returns the callback configuration as set by BrickletEnergyMonitor#set_energy_data_callback_configuration.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 213
def get_energy_data_callback_configuration
  check_validity

  send_request FUNCTION_GET_ENERGY_DATA_CALLBACK_CONFIGURATION, [], '', 13, 'L ?'
end
get_identity() click to toggle source

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an :ref:`Isolator Bricklet <isolator_bricklet>` is always at position 'z'.

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 357
def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end
get_spitfp_error_count() click to toggle source

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,

  • message checksum errors,

  • framing errors and

  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 230
def get_spitfp_error_count
  check_validity

  send_request FUNCTION_GET_SPITFP_ERROR_COUNT, [], '', 24, 'L L L L'
end
get_status_led_config() click to toggle source

Returns the configuration as set by BrickletEnergyMonitor#set_status_led_config

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 298
def get_status_led_config
  check_validity

  send_request FUNCTION_GET_STATUS_LED_CONFIG, [], '', 9, 'C'
end
get_transformer_calibration() click to toggle source

Returns the transformer calibration as set by BrickletEnergyMonitor#set_transformer_calibration.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 172
def get_transformer_calibration
  check_validity

  send_request FUNCTION_GET_TRANSFORMER_CALIBRATION, [], '', 14, 'S S s'
end
get_transformer_status() click to toggle source

Returns true if a voltage/current transformer is connected to the Bricklet.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 147
def get_transformer_status
  check_validity

  send_request FUNCTION_GET_TRANSFORMER_STATUS, [], '', 10, '? ?'
end
get_waveform() click to toggle source

Returns a snapshot of the voltage and current waveform. The values in the returned array alternate between voltage and current. The data from one getter call contains 768 data points for voltage and current, which correspond to about 3 full sine waves.

The voltage is given with a resolution of 100mV and the current is given with a resolution of 10mA.

This data is meant to be used for a non-realtime graphical representation of the voltage and current waveforms.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 371
def get_waveform
  waveform_length = 1536
  waveform_data = nil # assigned in block

  @stream_mutex.synchronize {
    ret = get_waveform_low_level
    waveform_chunk_offset = ret[0]

    if waveform_chunk_offset == (1 << 16) - 1 # maximum chunk offset -> stream has no data
      waveform_length = 0
      waveform_chunk_offset = 0
      waveform_out_of_sync = false
      waveform_data = []
    else
      waveform_out_of_sync = waveform_chunk_offset != 0
      waveform_data = ret[1]
    end

    while not waveform_out_of_sync and waveform_data.length < waveform_length
      ret = get_waveform_low_level
      waveform_chunk_offset = ret[0]
      waveform_out_of_sync = waveform_chunk_offset != waveform_data.length
      waveform_data += ret[1]
    end

    if waveform_out_of_sync # discard remaining stream to bring it back in-sync
      while waveform_chunk_offset + 30 < waveform_length
        ret = get_waveform_low_level
        waveform_chunk_offset = ret[0]
      end

      raise StreamOutOfSyncException, 'Waveform stream is out-of-sync'
    end
  }

  waveform_data[0, waveform_length]
end
get_waveform_low_level() click to toggle source

Returns a snapshot of the voltage and current waveform. The values in the returned array alternate between voltage and current. The data from one getter call contains 768 data points for voltage and current, which correspond to about 3 full sine waves.

The voltage is given with a resolution of 100mV and the current is given with a resolution of 10mA.

This data is meant to be used for a non-realtime graphical representation of the voltage and current waveforms.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 140
def get_waveform_low_level
  check_validity

  send_request FUNCTION_GET_WAVEFORM_LOW_LEVEL, [], '', 70, 'S s30'
end
read_uid() click to toggle source

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 341
def read_uid
  check_validity

  send_request FUNCTION_READ_UID, [], '', 12, 'L'
end
register_callback(id, &block) click to toggle source

Registers a callback with ID id to the block block.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 410
def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end
reset() click to toggle source

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 322
def reset
  check_validity

  send_request FUNCTION_RESET, [], '', 8, ''
end
reset_energy() click to toggle source

Sets the energy value (see BrickletEnergyMonitor#get_energy_data) back to 0Wh.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 124
def reset_energy
  check_validity

  send_request FUNCTION_RESET_ENERGY, [], '', 8, ''
end
set_bootloader_mode(mode) click to toggle source

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 245
def set_bootloader_mode(mode)
  check_validity

  send_request FUNCTION_SET_BOOTLOADER_MODE, [mode], 'C', 9, 'C'
end
set_energy_data_callback_configuration(period, value_has_to_change) click to toggle source

The period is the period with which the CALLBACK_ENERGY_DATA callback is triggered periodically. A value of 0 turns the callback off.

If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 205
def set_energy_data_callback_configuration(period, value_has_to_change)
  check_validity

  send_request FUNCTION_SET_ENERGY_DATA_CALLBACK_CONFIGURATION, [period, value_has_to_change], 'L ?', 8, ''
end
set_status_led_config(config) click to toggle source

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 291
def set_status_led_config(config)
  check_validity

  send_request FUNCTION_SET_STATUS_LED_CONFIG, [config], 'C', 8, ''
end
set_transformer_calibration(voltage_ratio, current_ratio, phase_shift) click to toggle source

Sets the transformer ratio for the voltage and current transformer in 1/100 form.

Example: If your mains voltage is 230V, you use 9V voltage transformer and a 1V:30A current clamp your voltage ratio is 230/9 = 25.56 and your current ratio is 30/1 = 30.

In this case you have to set the values 2556 and 3000 for voltage ratio and current ratio.

The calibration is saved in non-volatile memory, you only have to set it once.

Set the phase shift to 0. It is for future use and currently not supported by the Bricklet.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 165
def set_transformer_calibration(voltage_ratio, current_ratio, phase_shift)
  check_validity

  send_request FUNCTION_SET_TRANSFORMER_CALIBRATION, [voltage_ratio, current_ratio, phase_shift], 'S S s', 8, ''
end
set_write_firmware_pointer(pointer) click to toggle source

Sets the firmware pointer for BrickletEnergyMonitor#write_firmware. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 264
def set_write_firmware_pointer(pointer)
  check_validity

  send_request FUNCTION_SET_WRITE_FIRMWARE_POINTER, [pointer], 'L', 8, ''
end
write_firmware(data) click to toggle source

Writes 64 Bytes of firmware at the position as written by BrickletEnergyMonitor#set_write_firmware_pointer before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 278
def write_firmware(data)
  check_validity

  send_request FUNCTION_WRITE_FIRMWARE, [data], 'C64', 9, 'C'
end
write_uid(uid) click to toggle source

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

# File lib/tinkerforge/bricklet_energy_monitor.rb, line 333
def write_uid(uid)
  check_validity

  send_request FUNCTION_WRITE_UID, [uid], 'L', 8, ''
end