nibcq.LCRACIR

class nibcq.LCRACIR(device: nibcq._device.Device, test_parameters: LCRTestParameters)

Bases: nibcq.measurement.Measurement

LCR-based ACIR (AC Internal Resistance) measurement handler class.

This class implements single-frequency AC impedance measurements using the NI PXIe-4190 LCR Meter. Unlike SMU-based ACIR which uses waveform generation and FFT analysis, the LCR meter performs hardware-based impedance measurements directly at 1000 Hz.

The LCR meter handles all signal generation and analysis internally, making measurements simpler and faster than SMU-based methods. Compensation is applied via hardware settings (onboard storage), not post-processing, so the _run_workflow() override skips the _calculate() and _apply_compensation() steps entirely - only _configure() and _measure() are executed.

Inherits from Measurement to follow the Template Method pattern: validate → lock → configure → measure → (calculate) → (compensate) → result.

Parameters:

device (nibcq._device.Device)
test_parameters (LCRTestParameters)

DEVICE_FAMILY

DeviceFamily.LCR_METER - required device type.

Type:: DeviceFamily

DEFAULT_MEASUREMENT_FREQUENCY

Default frequency constant for ACIR (1000.0 Hz).

Type:: float

MEASUREMENT_TIMEOUT

21.0 seconds - timeout for measurement completion.

Type:: float

Examples

>>> device = Device.create(DeviceFamily.LCR_METER, "PXI1Slot2")
>>> params = LCRTestParameters(current_amplitude=0.07)
>>> lcr_acir = LCRACIR(device, params)
>>> result = lcr_acir.run()
>>> print(f"Impedance: {result.z_magnitude:.4f} Ohm")

property result: nibcq.measurement.LCRMeasurementResult | None

Get the last measurement result.

Returns:

The last measurement result, or None if no: measurement has been performed yet.

Return type:

LCRMeasurementResult

property measurement_frequency: float

Get the current measurement frequency.

Returns:: The measurement frequency in Hz.
Return type:: float

static validate_current_amplitude(current_amplitude: float) → bool

Validate that the current amplitude is within acceptable limits.

Parameters:: current_amplitude (float) – The current amplitude to validate in Amperes RMS.
Returns:: Always returns True when validation passes.
Return type:: bool
Raises:: LCRParameterError – If the current amplitude is outside the valid range (7.08 nA to 707 mA).

create_compensation(params: nibcq.lcr_compensation.LCRCompensationParameters, skip_prompts: bool = False) → nibcq.measurement.LCRMeasurementResult

Generate LCR compensation data and verify with a measurement.

This method performs the complete 7-step compensation generation flow as defined in the LabVIEW “Create Compensation” example:

Session init (already done via Device.create)
Custom cable compensation (if enabled)
Set cable length
Open/Short compensation (if enabled)
Load compensation (if enabled)
Configure session for verification measurement
Verification measurement (initiate, wait, measure, reset)

The compensation data is stored on the device’s onboard memory and remains available for subsequent measurements until the device is reset or powered off.

User prompts are displayed before each step requiring physical connection changes (open, short, load). These prompts ensure the user has made the correct physical setup before compensation data is captured.

Parameters:

params (LCRCompensationParameters) – LCRCompensationParameters with all configuration options.
skip_prompts (bool) – If True, skips user prompts for physical connections. User must ensure correct connections are made before each step. Useful for automated testing or scripted calibration sequences. Follows the Calibrator.self_calibrate(force=…) pattern.

Returns:

Verification measurement result after: compensation is applied. Can be used to verify compensation quality (should show near-zero impedance for a short).

Return type:

LCRMeasurementResult

Raises:

LCRParameterError – If parameters are invalid (e.g., load comp without open AND short).
nidcpower.Error – If hardware operation fails.

Examples

>>> # Interactive compensation with user prompts
>>> lcr = LCRACIR(device, test_params)
>>> result = lcr.create_compensation(
...     LCRCompensationParameters(
...         generate_open=True,
...         generate_short=True,
...         enable_open=True,
...         enable_short=True,
...     )
... )
>>> print(f"Verification Z: {result.z_magnitude:.6f} Ohm")
>>>
>>> # Automated compensation (for testing)
>>> result = lcr.create_compensation(params, skip_prompts=True)

property test_parameters: TestParameters

Get the current test parameters for the measurement.

Returns the configuration parameters that define how the measurement should be performed, including settings like powerline frequency and other measurement-specific parameters.

Returns:: The current test parameters configuration
Return type:: TestParameters

Examples

>>> measurement = Measurement(device)
>>> params = measurement.test_parameters
>>> print(params.powerline_frequency)
PowerlineFrequency.FREQ_60_HZ

property compensation: Compensation | None

Get the compensation object for error correction.

Returns:: The compensation data, or None if no compensation is applied.
Return type:: Compensation | None

run(compensation: Compensation | None = None, **kwargs)

Run the measurement process (Template Method).

Defines the invariant measurement workflow:

Optionally set compensation from argument.
Store any extra keyword arguments in _run_kwargs so hook methods can access them.
Validate preconditions (temperature, etc.) — before locking.
Lock all device sessions.
Execute the workflow (configure → measure → calculate → compensate).
Release locks.
Clear _run_kwargs.
Return result.

Subclasses customize behavior by overriding the abstract/hook methods: _configure, _measure, _calculate, _apply_compensation, _validate_preconditions, _lock_sessions, _run_workflow.

Parameters:

compensation (Compensation | None) – Optional compensation data for error correction. If provided, sets self._compensation before running. If None, uses the previously set self._compensation (which may also be None, meaning no compensation is applied).
kwargs (Any) – Additional keyword arguments (**kwargs) forwarded to hook methods via self._run_kwargs. Subclasses may read specific keys from this dict inside their _run_workflow or other hooks.

Returns:

The measurement result (type depends on the specific subclass).

Return type:

Any

property acceptable_temperature_delta: float

Get the acceptable temperature delta for compensation validation.

Returns the maximum allowed temperature difference from the device’s temperature capability. This is a pass-through property that delegates to the underlying TemperatureCapability.

Returns:: The acceptable temperature delta in degrees, or NaN if no temperature capability
Return type:: float

Examples

>>> measurement = EIS(device)
>>> measurement.acceptable_temperature_delta = 2.5
>>> delta = measurement.acceptable_temperature_delta

property temperature: float

Get the latest temperature reading from the device.

Returns:: The most recent temperature measurement, or NaN if no temperature capability
Return type:: float

property temperature_range: CenteredRange

Get the latest temperature reading from the device, coupled with the user-set delta.

Returns:: A CenteredRange representing the most recent temperature measurement (NaN if not available), along with the acceptable temperature delta (NaN if not set).
Return type:: CenteredRange

measure_temperature() → CenteredRange

Get a new temperature reading from the device.

Returns:: Current temperature reading, or NaN if no temperature capability
Return type:: CenteredRange

validate_temperature(target_temperature: CenteredRange) → bool

Validate the current temperature against the compensation file’s target.

Delegates to the device’s temperature capability for validation. The capability handles all validation logic including checking if thermocouple is configured, using overridden delta values if set, and printing appropriate warnings.

Parameters:

target_temperature (CenteredRange) – The target temperature parameters for validation

Returns:

True if thermocouple is configured and temperature is within range.: False if thermocouple is not configured (capability missing or not set up), or if target temperature/delta is NaN.

Return type:

bool

Raises:

TemperatureError – If the current temperature exceeds the target ± delta range (only raised when capability is configured)

Examples

>>> measurement = EIS(device)
>>> measurement.measure_temperature()
>>> target = compensation.temperature_parameter
>>> is_valid = measurement.validate_temperature(target)