API Documentation
SF06-LF
Sf06LfDevice
The class Sf06LfDeviceBase implements the low level interface of the sensor. The class Sf06LfDevice extends the Sf06LfDeviceBase. It provides additional functions to ease the use of the sensor.
- class sensirion_i2c_sf06_lf.device.Sf06LfDeviceBase(channel)[source]
Low level API implementation of SF06_LF
- property channel
- start_h2o_continuous_measurement()[source]
Starts continuous measurement mode using calibration values for H₂O. The sensor measures both the flow rate and the temperature. After the command has been sent, the chip continuously measures and updates the measurement results which can be read with read_measurement_data_raw.
Note
The first measurement result will be available after 12ms. Due to the thermal measurement principle small accuracy deviations (% m.v.) can occur while the sensor warms-up (60ms for SLF3x, 120ms for LD2x including the 12 ms for measurement initialization).
- start_ipa_continuous_measurement()[source]
Starts continuous measurement mode using calibration values for Isopropyl alcohol. The sensor measures both the flow rate and the temperature. After the command has been sent, the chip continuously measures and updates the measurement results which can be read with read_measurement_data_raw. Supported by products: SLF3C-1300F, SLF3S-1300F, SLF3S-0600F, SLF3S-4000B
Note
The first measurement result will be available after 12ms. Due to the thermal measurement principle small accuracy deviations (% m.v.) can occur while the sensor warms-up (60ms for SLF3x, 120ms for LD2x including the 12 ms for measurement initialization).
- read_measurement_data_raw()[source]
After the command start_xx_continuous_measurement has been sent, the chip continuously measures and updates the measurement results. New results (flow, temperature, and signaling flags) can be read continuously with this command.
- Return raw_flow
For SLF3C-1300F, SLF3S-1300F convert to ml/min by applying: flow = raw_flow / 500 For SLF3S-4000B convert to ml/min by applying: flow = raw_flow / 32 For SLF3S-0600F convert to μl/min by applying: flow = raw_flow / 10 For LD20-0600L convert to ml/h by applying: flow = raw_flow / 1200 For LD20-2600B convert to ml/h by applying: flow = raw_flow / 20
- Return raw_temperature
Convert to degrees celsius by temperature = raw_temperature / 200
- Return signaling_flags
Gives additional information about the measurement status. Refer to the sensor data sheet for detailed information. Following flags are defined: Air-in-Line flag (Bit 0), High Flow flag (Bit 1), Exponential smoothing active (Bit 5)
Note
The first measurement result will be available 12ms after starting the measurement. Small accuracy deviations (% m.v.) can occur during the first 60ms for SLF3x, 120ms for LD2x (including the 12ms initialization)
- stop_continuous_measurement()[source]
This command stops the continuous measurement and puts the sensor in idle mode. After it receives the stop command, the sensor needs up to 0.5ms to power down the heater, enter idle mode and be receptive for a new command.
- start_single_thermal_conductivity_measurement_sync()[source]
This command starts one thermal conductivity measurement and blocks for 2.3 seconds until the measurement results are ready. After completion of the measurement, the heater is switched off and the sensor enters idle mode and the results can be read anytime with read_thermal_conductivity_measurement_data. The sensor measures the thermal conductivity, the sensor temperature, and the delta-temperature (a measure for the temperature difference between the liquid and the sensor). Supported by products: SLF3C-1300F, SLF3S-4000B
- start_single_thermal_conductivity_measurement_async()[source]
This command starts one thermal conductivity measurement and returns immediately. Note that the sensor does not accept any other commands while the measurement is running, which takes approximately 2.3 seconds. After completion of the measurement, the heater is switched off and the sensor enters idle mode and the results can be read anytime with read_thermal_conductivity_measurement_data. The sensor measures the thermal conductivity, the sensor temperature, and the delta-temperature (a measure for the temperature difference between the liquid and the sensor). Supported by products: SLF3C-1300F, SLF3S-4000B
- read_thermal_conductivity_measurement_data()[source]
Reads single thermal conductivity measurement after a measurement has been started with start_single_thermal_conductivity_measurement_sync or start_single_thermal_conductivity_measurement_async. Supported by products: SLF3C-1300F, SLF3S-4000B
- Return thermal_conductivity
thermal conductivity
- Return raw_temperature
Convert to degrees celsius by temperature = raw_temperature / 200
- Return raw_delta_temperature
The delta-temperature is a measure for the temperature difference between the liquid and the sensor. Convert to degrees celsius by delta_temperature = raw_delta_temperature / 1000
- enter_sleep()[source]
In sleep mode the sensor uses a minimum amount of power. The mode can only be entered from idle mode, i.e. when the sensor is not measuring. This mode is particularly useful for battery operated devices. To minimize the current in this mode, the complexity of the sleep mode circuit has been reduced as much as possible, which is mainly reflected by the way the sensor exits the sleep mode. In sleep mode the sensor cannot be soft reset. Supported by products: LD20-0600L, LD20-2600B
- exit_sleep()[source]
The sensor exits the sleep mode and enters the idle mode when it receives the valid I2C address and a write bit (‘0’). Note that the I2C address is not acknowledged. It is necessary to poll the sensor to see whether the sensor has received the address and has woken up. This should take typically 25ms. Supported by products: LD20-0600L, LD20-2600B
- read_product_identifier_prepare()[source]
Prepare to read the product identifier and the serial number. The command can only be executed from the idle mode, i.e. when the sensor is not performing measurements.
- read_product_identifier()[source]
This command allows to read product identifier and the serial number. The command can only be executed from the idle mode, i.e. when the sensor is not performing measurements and read_product_identifier_prepare is called before.
- Return product_identifier
Note that the last 8 bits are the sensor’s revision number and are subject to change in case of an update of the specifications.
- Return serial_number
serial number
- class sensirion_i2c_sf06_lf.device.Sf06LfDevice(channel)[source]
Driver class implementation of SF06_LF
- sf06_lf
Access to base class
- read_measurement_data(inv_flow_scale_factor)[source]
Reads the raw measurement values and converts them to their physcial units where applicable. For the flow the scaling factor and resulting flow unit depends on the specific sensor. The scaling factor is passed as an argument and the raw flow value is converted by applying: flow = raw_flow / inv_flow_scale_factor The scaling factors for the supported sensor are defined in enum inv_flow_scale_factors
- Parameters
inv_flow_scale_factor – used to convert raw flow value
- Return a_flow
As the flow scaling differs for specific sensor types the scaling factor must be passed as an argument. See the enum inv_flow_scale_factors for scaling factors of supported sensors. The raw value is converted by: flow = raw_flow / inv_flow_scale_factor Resulting unit depends on your specific sensor type.
- Return a_temperature
temperature in degree celsius
- Return a_signaling_flags
- read_thermal_conductivity_measurement_data()[source]
Reads single thermal conductivity measurement after a measurement has been started with start_single_thermal_conductivity_measurement. Supported by products: SLF3C-1300F, SLF3S-4000B
- Return a_thermal_conductivity
thermal conductivity in arbitary unit
- Return a_temperature
temperature in degree celsius
- Return a_delta_temperature
delta temperature in degree celsius
- read_product_identifier()[source]
Read product identifier and the serial number. The command can only be executed from the idle mode, i.e. when the sensor is not performing measurements.
- Return product_identifier
Note that the last 8 bits are the sensor’s revision number and are subject to change in case of an update of the specifications.
- Return serial_number
serial number
Commands
The transfer classes specify the data that is transferred between host and sensor. The generated transfer classes are used by the driver class and not intended for direct use.
- class sensirion_i2c_sf06_lf.commands.InvFlowScaleFactors(value)[source]
An enumeration.
- SLF3C_1300F = 500
- SLF3S_1300F = 500
- SLF3S_4000B = 32
- SLF3S_0600F = 10
- LD20_0600L = 1200
- LD20_2600B = 20
- class sensirion_i2c_sf06_lf.commands.SignalingFlagsT(int_value: int = 0)[source]
- air_in_line_flag = BitField(offset=0, width=1)
- high_flow_flag = BitField(offset=1, width=1)
- exp_smoothing_active = BitField(offset=5, width=1)
- class sensirion_i2c_sf06_lf.commands.StartH2oContinuousMeasurement[source]
Starts continuous measurement mode using calibration values for H₂O. The sensor measures both the flow rate and the temperature. After the command has been sent, the chip continuously measures and updates the measurement results which can be read with read_measurement_data_raw.
- CMD_ID = 13832
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.StartIpaContinuousMeasurement[source]
Starts continuous measurement mode using calibration values for Isopropyl alcohol. The sensor measures both the flow rate and the temperature. After the command has been sent, the chip continuously measures and updates the measurement results which can be read with read_measurement_data_raw. Supported by products: SLF3C-1300F, SLF3S-1300F, SLF3S-0600F, SLF3S-4000B
- CMD_ID = 13845
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.ReadMeasurementDataRaw[source]
After the command start_xx_continuous_measurement has been sent, the chip continuously measures and updates the measurement results. New results (flow, temperature, and signaling flags) can be read continuously with this command.
- rx = <sensirion_driver_adapters.rx_tx_data.RxData object>
- class sensirion_i2c_sf06_lf.commands.StopContinuousMeasurement[source]
This command stops the continuous measurement and puts the sensor in idle mode. After it receives the stop command, the sensor needs up to 0.5ms to power down the heater, enter idle mode and be receptive for a new command.
- CMD_ID = 16377
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.StartSingleThermalConductivityMeasurementSync[source]
This command starts one thermal conductivity measurement and blocks for 2.3 seconds until the measurement results are ready. After completion of the measurement, the heater is switched off and the sensor enters idle mode and the results can be read anytime with read_thermal_conductivity_measurement_data. The sensor measures the thermal conductivity, the sensor temperature, and the delta-temperature (a measure for the temperature difference between the liquid and the sensor). Supported by products: SLF3C-1300F, SLF3S-4000B
- CMD_ID = 13894
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.StartSingleThermalConductivityMeasurementAsync[source]
This command starts one thermal conductivity measurement and returns immediately. Note that the sensor does not accept any other commands while the measurement is running, which takes approximately 2.3 seconds. After completion of the measurement, the heater is switched off and the sensor enters idle mode and the results can be read anytime with read_thermal_conductivity_measurement_data. The sensor measures the thermal conductivity, the sensor temperature, and the delta-temperature (a measure for the temperature difference between the liquid and the sensor). Supported by products: SLF3C-1300F, SLF3S-4000B
- CMD_ID = 13894
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.ReadThermalConductivityMeasurementData[source]
Reads single thermal conductivity measurement after a measurement has been started with start_single_thermal_conductivity_measurement_sync or start_single_thermal_conductivity_measurement_async. Supported by products: SLF3C-1300F, SLF3S-4000B
- rx = <sensirion_driver_adapters.rx_tx_data.RxData object>
- class sensirion_i2c_sf06_lf.commands.EnterSleep[source]
In sleep mode the sensor uses a minimum amount of power. The mode can only be entered from idle mode, i.e. when the sensor is not measuring. This mode is particularly useful for battery operated devices. To minimize the current in this mode, the complexity of the sleep mode circuit has been reduced as much as possible, which is mainly reflected by the way the sensor exits the sleep mode. In sleep mode the sensor cannot be soft reset. Supported by products: LD20-0600L, LD20-2600B
- CMD_ID = 13943
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.ExitSleep[source]
The sensor exits the sleep mode and enters the idle mode when it receives the valid I2C address and a write bit (‘0’). Note that the I2C address is not acknowledged. It is necessary to poll the sensor to see whether the sensor has received the address and has woken up. This should take typically 25ms. Supported by products: LD20-0600L, LD20-2600B
- CMD_ID = 0
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.ReadProductIdentifierPrepare[source]
Prepare to read the product identifier and the serial number. The command can only be executed from the idle mode, i.e. when the sensor is not performing measurements.
- CMD_ID = 13948
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- class sensirion_i2c_sf06_lf.commands.ReadProductIdentifier[source]
This command allows to read product identifier and the serial number. The command can only be executed from the idle mode, i.e. when the sensor is not performing measurements and read_product_identifier_prepare is called before.
- CMD_ID = 57602
- tx = <sensirion_driver_adapters.rx_tx_data.TxData object>
- rx = <sensirion_driver_adapters.rx_tx_data.RxData object>
Result Types
The signal classes specify transformations of the raw sensor signals into a meaningful units. The generated signal types are used by the driver class and not intended for direct use.
- class sensirion_i2c_sf06_lf.result_types.SignalFlow(raw_flow, inv_flow_scale_factor)[source]
As the flow scaling differs for specific sensor types the scaling factor must be passed as an argument. See the enum inv_flow_scale_factors for scaling factors of supported sensors. The raw value is converted by: flow = raw_flow / inv_flow_scale_factor Resulting unit depends on your specific sensor type.
- property value
- class sensirion_i2c_sf06_lf.result_types.SignalTemperature(raw_temperature)[source]
temperature in degree celsius
- property value