LabVIEW - Energy Monitor Bricklet

This is the description of the LabVIEW API bindings for the Energy Monitor Bricklet. General information and technical specifications for the Energy Monitor Bricklet are summarized in its hardware description.

An installation guide for the LabVIEW API bindings is part of their general description.

API

Generally, every function of the LabVIEW bindings that outputs a value can report a Tinkerforge.TimeoutException. This error gets reported if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

Basic Functions

BrickletEnergyMonitor(uid, ipcon) → energyMonitor
Input:
  • uid – Type: String
  • ipcon – Type: .NET Refnum (IPConnection)
Output:
  • energyMonitor – Type: .NET Refnum (BrickletEnergyMonitor)

Creates an object with the unique device ID uid. This object can then be used after the IP Connection is connected.

BrickletEnergyMonitor.GetEnergyData() → voltage, current, energy, realPower, apparentPower, reactivePower, powerFactor, frequency
Output:
  • voltage – Type: Int32, Unit: 1/100 V, Range: [-231 to 231 - 1]
  • current – Type: Int32, Unit: 1/100 A, Range: [-231 to 231 - 1]
  • energy – Type: Int32, Unit: 1/100 Wh, Range: [-231 to 231 - 1]
  • realPower – Type: Int32, Unit: 1/100 W, Range: [-231 to 231 - 1]
  • apparentPower – Type: Int32, Unit: 1/100 VA, Range: [-231 to 231 - 1]
  • reactivePower – Type: Int32, Unit: 1/100 var, Range: [-231 to 231 - 1]
  • powerFactor – Type: Int32, Unit: 1/1000, Range: [0 to 216 - 1]
  • frequency – Type: Int32, Unit: 1/100 Hz, Range: [0 to 216 - 1]

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.

BrickletEnergyMonitor.ResetEnergy()

Sets the energy value (see GetEnergyData()) back to 0Wh.

BrickletEnergyMonitor.GetWaveform() → waveform
Output:
  • waveform – Type: Int16[1536], Range: [-215 to 215 - 1]

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.

BrickletEnergyMonitor.GetTransformerStatus() → voltageTransformerConnected, currentTransformerConnected
Output:
  • voltageTransformerConnected – Type: Boolean
  • currentTransformerConnected – Type: Boolean

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

BrickletEnergyMonitor.SetTransformerCalibration(voltageRatio, currentRatio, phaseShift)
Input:
  • voltageRatio – Type: Int32, Range: [0 to 216 - 1], Default: 1923
  • currentRatio – Type: Int32, Range: [0 to 216 - 1], Default: 3000
  • phaseShift – Type: Int16, Range: [0], Default: 0

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.

BrickletEnergyMonitor.GetTransformerCalibration() → voltageRatio, currentRatio, phaseShift
Output:
  • voltageRatio – Type: Int32, Range: [0 to 216 - 1], Default: 1923
  • currentRatio – Type: Int32, Range: [0 to 216 - 1], Default: 3000
  • phaseShift – Type: Int16, Range: [0], Default: 0

Returns the transformer calibration as set by SetTransformerCalibration().

BrickletEnergyMonitor.CalibrateOffset()

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.

Advanced Functions

BrickletEnergyMonitor.GetSPITFPErrorCount() → errorCountAckChecksum, errorCountMessageChecksum, errorCountFrame, errorCountOverflow
Output:
  • errorCountAckChecksum – Type: Int64, Range: [0 to 232 - 1]
  • errorCountMessageChecksum – Type: Int64, Range: [0 to 232 - 1]
  • errorCountFrame – Type: Int64, Range: [0 to 232 - 1]
  • errorCountOverflow – Type: Int64, Range: [0 to 232 - 1]

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.

BrickletEnergyMonitor.SetStatusLEDConfig(config)
Input:
  • config – Type: Byte, Range: See constants, Default: 3

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.

The following constants are available for this function:

For config:

  • BrickletEnergyMonitor.STATUS_LED_CONFIG_OFF = 0
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_ON = 1
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_SHOW_STATUS = 3
BrickletEnergyMonitor.GetStatusLEDConfig() → config
Output:
  • config – Type: Byte, Range: See constants, Default: 3

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

For config:

  • BrickletEnergyMonitor.STATUS_LED_CONFIG_OFF = 0
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_ON = 1
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletEnergyMonitor.STATUS_LED_CONFIG_SHOW_STATUS = 3
BrickletEnergyMonitor.GetChipTemperature() → temperature
Output:
  • temperature – Type: Int16, Unit: 1 °C, Range: [-215 to 215 - 1]

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.

BrickletEnergyMonitor.Reset()

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!

BrickletEnergyMonitor.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier
Output:
  • uid – Type: String, Length: up to 8
  • connectedUid – Type: String, Length: up to 8
  • position – Type: Char, Range: ["a" to "h", "z"]
  • hardwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • firmwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • deviceIdentifier – Type: Int32, Range: [0 to 216 - 1]

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 Isolator Bricklet is always at position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

BrickletEnergyMonitor.SetEnergyDataCallbackConfiguration(period, valueHasToChange)
Input:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • valueHasToChange – Type: Boolean, Default: F

The period is the period with which the EnergyDataCallback 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.

BrickletEnergyMonitor.GetEnergyDataCallbackConfiguration() → period, valueHasToChange
Output:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • valueHasToChange – Type: Boolean, Default: F

Returns the callback configuration as set by SetEnergyDataCallbackConfiguration().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a function to a callback property of the device object. The available callback property and their type of parameters are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

event BrickletEnergyMonitor.EnergyDataCallback → sender, voltage, current, energy, realPower, apparentPower, reactivePower, powerFactor, frequency
Callback Output:
  • sender – Type: .NET Refnum (BrickletEnergyMonitor)
  • voltage – Type: Int32, Unit: 1/100 V, Range: [-231 to 231 - 1]
  • current – Type: Int32, Unit: 1/100 A, Range: [-231 to 231 - 1]
  • energy – Type: Int32, Unit: 1/100 Wh, Range: [-231 to 231 - 1]
  • realPower – Type: Int32, Unit: 1/100 W, Range: [-231 to 231 - 1]
  • apparentPower – Type: Int32, Unit: 1/100 VA, Range: [-231 to 231 - 1]
  • reactivePower – Type: Int32, Unit: 1/100 var, Range: [-231 to 231 - 1]
  • powerFactor – Type: Int32, Unit: 1/1000, Range: [0 to 216 - 1]
  • frequency – Type: Int32, Unit: 1/100 Hz, Range: [0 to 216 - 1]

This callback is triggered periodically according to the configuration set by SetEnergyDataCallbackConfiguration().

The parameters are the same as GetEnergyData().

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

BrickletEnergyMonitor.GetAPIVersion() → apiVersion
Output:
  • apiVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

BrickletEnergyMonitor.GetResponseExpected(functionId) → responseExpected
Input:
  • functionId – Type: Byte, Range: See constants
Output:
  • responseExpected – Type: Boolean

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletEnergyMonitor.FUNCTION_RESET_ENERGY = 2
  • BrickletEnergyMonitor.FUNCTION_SET_TRANSFORMER_CALIBRATION = 5
  • BrickletEnergyMonitor.FUNCTION_CALIBRATE_OFFSET = 7
  • BrickletEnergyMonitor.FUNCTION_SET_ENERGY_DATA_CALLBACK_CONFIGURATION = 8
  • BrickletEnergyMonitor.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletEnergyMonitor.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletEnergyMonitor.FUNCTION_RESET = 243
  • BrickletEnergyMonitor.FUNCTION_WRITE_UID = 248
BrickletEnergyMonitor.SetResponseExpected(functionId, responseExpected)
Input:
  • functionId – Type: Byte, Range: See constants
  • responseExpected – Type: Boolean

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletEnergyMonitor.FUNCTION_RESET_ENERGY = 2
  • BrickletEnergyMonitor.FUNCTION_SET_TRANSFORMER_CALIBRATION = 5
  • BrickletEnergyMonitor.FUNCTION_CALIBRATE_OFFSET = 7
  • BrickletEnergyMonitor.FUNCTION_SET_ENERGY_DATA_CALLBACK_CONFIGURATION = 8
  • BrickletEnergyMonitor.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletEnergyMonitor.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletEnergyMonitor.FUNCTION_RESET = 243
  • BrickletEnergyMonitor.FUNCTION_WRITE_UID = 248
BrickletEnergyMonitor.SetResponseExpectedAll(responseExpected)
Input:
  • responseExpected – Type: Boolean

Changes the response expected flag for all setter and callback configuration functions of this device at once.

Internal Functions

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

BrickletEnergyMonitor.SetBootloaderMode(mode) → status
Input:
  • mode – Type: Byte, Range: See constants
Output:
  • status – Type: Byte, Range: See constants

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.

The following constants are available for this function:

For mode:

  • BrickletEnergyMonitor.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletEnergyMonitor.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For status:

  • BrickletEnergyMonitor.BOOTLOADER_STATUS_OK = 0
  • BrickletEnergyMonitor.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletEnergyMonitor.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletEnergyMonitor.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletEnergyMonitor.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletEnergyMonitor.BOOTLOADER_STATUS_CRC_MISMATCH = 5
BrickletEnergyMonitor.GetBootloaderMode() → mode
Output:
  • mode – Type: Byte, Range: See constants

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

For mode:

  • BrickletEnergyMonitor.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletEnergyMonitor.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletEnergyMonitor.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
BrickletEnergyMonitor.SetWriteFirmwarePointer(pointer)
Input:
  • pointer – Type: Int64, Unit: 1 B, Range: [0 to 232 - 1]

Sets the firmware pointer for WriteFirmware(). 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.

BrickletEnergyMonitor.WriteFirmware(data) → status
Input:
  • data – Type: Byte[64], Range: [0 to 255]
Output:
  • status – Type: Byte, Range: [0 to 255]

Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer() 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.

BrickletEnergyMonitor.WriteUID(uid)
Input:
  • uid – Type: Int64, Range: [0 to 232 - 1]

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.

BrickletEnergyMonitor.ReadUID() → uid
Output:
  • uid – Type: Int64, Range: [0 to 232 - 1]

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

Constants

BrickletEnergyMonitor.DEVICE_IDENTIFIER

This constant is used to identify a Energy Monitor Bricklet.

The GetIdentity() function and the IPConnection.EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

BrickletEnergyMonitor.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Energy Monitor Bricklet.