TDMS_CreateStrainGageScalingInfo
- Updated2023-02-21
- 3 minute(s) read
TDMS_CreateStrainGageScalingInfo
int TDMS_CreateStrainGageScalingInfo (TDMSAnyHandle handle, TDMSStrainGaugeConfig configuration, double poissonRatio, double gageResistance, double leadWireResistance, double initialBridgeVoltage, double gageFactor, double voltageExcitation, int inputSource, int *scaleID);
Purpose
Creates strain gage scaling information for one or more channels. Strain is the amount of deformation of a body due to an applied force. Specifically, strain is the fractional change in length.
Once scaling information has been created for a channel, TDMS_GetDataType will report the type of the channel as TDMS_Double and TDMS_GetDataValues will return the scaled data values. The read functions in the Advanced Synchronous and Asynchronous I/O class will still return the unscaled data values.
(Linux) This function is not supported.
Parameters
| Input | ||||||||||||||||||
| Name | Type | Description | ||||||||||||||||
| handle | TDMSAnyHandle | A file, channel group, or channel handle. The scaling information is stored as properties of the specified file, channel group, or channel. If you pass a channel handle, the scaling information will apply only to that channel. If you pass a channel group handle, the scaling information will apply to all channels in that channel group. If you pass a file handle, the scaling information will apply to all channels in that file. If scaling information has been created at multiple levels, the scaling information at the most specific level will take precedence. For example, scaling information on a channel will take precedence over scaling information on the containing channel group or the containing file. |
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| configuration | TDMSStrainGaugeConfig | The bridge configuration for the strain gages.
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| poissonRatio | double | The ratio of lateral strain to axial strain in the material you are measuring. | ||||||||||||||||
| gageResistance | double | The resistance, in ohms, of the gages in an unstrained position. Each gage in the bridge must have the same nominal gage resistance. The resistance across arms of the bridge that do not have strain gages also must be the same as the nominal gage resistance. Refer to the sensor documentation to determine this value. | ||||||||||||||||
| leadWireResistance | double | The amount of resistance, in ohms, in the lead wires. Ideally, this value is the same for all leads. | ||||||||||||||||
| initialBridgeVoltage | double | The output voltage of the bridge, in volts, in the unloaded condition. This function subtracts this value from any measurements before applying scaling equations. Perform a voltage measurement on the bridge with no strain applied to determine this value. | ||||||||||||||||
| gageFactor | double | Specifies the sensitivity of the strain gages and relates the change in electrical resistance to the change in strain. Each gage in the bridge must have the same gage factor. Refer to the sensor documentation to determine this value. | ||||||||||||||||
| voltageExcitation | double | The amount of excitation, in volts, that the sensor requires. Refer to the sensor documentation to determine this value. | ||||||||||||||||
| inputSource | int | The scale ID representing the scaling information that will be applied before the scaling information added by this function is applied. Pass -1 if no scaling information should be applied first. When you pass -1 the scaling information added by this function will replace any existing scaling information for the specified file, channel group, or channel. You can use this parameter to combine multiple scales to create a compound scale. You do this by passing the value of the scaleID output parameter from one scaling function as the value of the inputSource input parameter of another scaling function. |
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| Output | ||||||||||||||||||
| Name | Type | Description | ||||||||||||||||
| scaleID | int | A scale ID representing the scaling information created by this function. If you passed a value other than -1 for the inputSource parameter, then this scale ID represents the cumulative scaling information represented by that parameter plus the scaling information created by this function. You only need this value if you want to pass it as the value of the inputSource parameter to another scaling function. If you do not need this value you can pass NULL for this parameter. |
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Return Value
| Name | Type | Description |
| status | int | Return value indicating whether the function was successful. Unless otherwise stated, zero represents successful execution and a negative number represents the error code. Error codes are defined in cvi\include\cvitdms.h. |
Additional Information
Library: TDM Streaming Library
Include file: cvitdms.h
LabWindows/CVI compatibility: LabWindows/CVI 2013 and later
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