Product Introduction
The NI-9242 is a C Series voltage input module designed for high-voltage AC and power measurement applications. It provides three simultaneously sampled voltage input channels with 24-bit analog-to-digital conversion for accurate measurement of single-phase and three-phase electrical systems.
The NI-9242 can measure up to 250 Vrms line-to-neutral (L-N) and 400 Vrms line-to-line (L-L), allowing direct connection to many common electrical power systems without requiring external voltage attenuation hardware.
When installed in a compatible CompactDAQ or CompactRIO system, the NI-9242 can be combined with current input modules to create a modular power measurement platform for voltage, current, power, energy, harmonics, power quality, and electrical equipment testing.
Product Overview
The National Instruments NI-9242 is designed specifically for electrical voltage and power measurements rather than conventional low-level analog data acquisition.
Its three-channel architecture is particularly suitable for three-phase systems:
Phase A Voltage → Channel 0
Phase B Voltage → Channel 1
Phase C Voltage → Channel 2
The module can be installed in compatible CompactDAQ or CompactRIO hardware to build scalable electrical measurement systems.
Key Features
3 Voltage Input Channels
The NI-9242 provides three analog voltage input channels.
This channel configuration is optimized for measurements in three-phase electrical systems and can also be used for other multichannel voltage measurement applications.
250 Vrms Line-to-Neutral Measurement
The NI-9242 supports direct measurement of voltages up to approximately 250 Vrms line-to-neutral.
This capability makes the module suitable for common electrical distribution and equipment-testing applications.
400 Vrms Line-to-Line Measurement
The module supports measurement of up to approximately 400 Vrms line-to-line.
This allows the NI-9242 to be used directly with many three-phase electrical systems without requiring an external voltage divider for normal operating voltages within the module’s specified range.
24-Bit Resolution
The NI-9242 uses 24-bit analog-to-digital converters to provide high-resolution voltage measurements.
High-resolution conversion is particularly valuable for power analysis where accurate waveform acquisition is required for calculating:
- RMS voltage
- Active power
- Reactive power
- Apparent power
- Power factor
- Frequency
- Harmonics
- Energy
Simultaneous Sampling
The three input channels are designed for simultaneous acquisition, which is important when comparing the phase relationship between multiple electrical signals.
Simultaneous sampling helps preserve phase information for:
- Three-phase power calculations
- Phase-angle measurement
- Power factor analysis
- Harmonic analysis
- Power quality testing
Designed for Power Measurement
Unlike general-purpose low-voltage analog input modules, the NI-9242 is optimized for direct voltage measurement in electrical power systems.
Typical applications include:
- AC power measurement
- Three-phase voltage measurement
- Power quality analysis
- Energy measurement
- Electrical equipment validation
- Grid monitoring
- Motor testing
- Inverter testing
C Series Architecture
The NI-9242 is part of the NI C Series modular I/O platform.
It can be installed in compatible CompactDAQ and CompactRIO systems alongside other C Series modules for current, temperature, digital, strain, vibration, and control measurements.
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Type | C Series Voltage Input Module |
| Model | NI-9242 |
| Manufacturer | National Instruments |
| Input Type | AC Voltage Measurement |
| Number of Channels | 3 |
| ADC Resolution | 24-Bit |
| Sampling Architecture | Simultaneous Sampling |
| Line-to-Neutral Measurement | Up to 250 Vrms |
| Line-to-Line Measurement | Up to 400 Vrms |
| Platform | NI C Series |
| Compatible System Families | CompactDAQ / CompactRIO |
| Primary Application | Electrical Power and Voltage Measurement |
How Does the NI-9242 Work?
The NI-9242 connects electrical voltage signals to a compatible NI C Series measurement system.
The module conditions and digitizes the voltage waveforms before transferring measurement data to the CompactDAQ or CompactRIO system.
A typical measurement architecture is:
AC Voltage Source → NI-9242 → CompactDAQ / CompactRIO → Measurement Software
The acquired waveform data can then be used to calculate RMS voltage, frequency, phase, harmonics, and other electrical parameters.
Three-Phase Voltage Measurement
The three-channel architecture makes the NI-9242 particularly suitable for three-phase electrical measurement.
A typical configuration is:
L1 → NI-9242 Channel 0
L2 → NI-9242 Channel 1
L3 → NI-9242 Channel 2
Depending on the electrical system and measurement configuration, the module can be used for phase-to-neutral and phase-to-phase voltage analysis within its specified limits.
Power Measurement with NI-9242
Voltage measurement alone is sufficient for voltage waveform analysis, but calculating electrical power generally requires both voltage and current measurements.
A modular power measurement system can therefore combine:
NI-9242 → Voltage Measurement
Compatible C Series Current Module → Current Measurement
CompactDAQ / CompactRIO → Synchronized Acquisition
Software → Power Analysis
This architecture can be used to calculate:
- RMS voltage
- RMS current
- Active power
- Reactive power
- Apparent power
- Power factor
- Energy
- Frequency
- Phase angle
- Harmonic distortion
Power Quality Measurement
The NI-9242 can acquire electrical voltage waveforms for power quality analysis.
Depending on the complete measurement system and software, engineers can analyze:
- Voltage RMS
- Frequency
- Voltage imbalance
- Harmonics
- Waveform distortion
- Voltage variations
- Phase relationships
Motor Testing
The NI-9242 can be used in motor and motor-drive test systems to acquire three-phase voltage waveforms.
When combined with synchronized current measurement, engineers can evaluate:
- Input voltage
- Current
- Electrical power
- Power factor
- Efficiency
- Harmonics
- Phase balance
Inverter Testing
Power electronic converters and inverters require synchronized voltage and current measurements for performance characterization.
The NI-9242 can be incorporated into modular test systems for:
- Solar inverter testing
- Motor inverter testing
- Power converter validation
- UPS testing
- Energy-storage system testing
- Electrical power research
Renewable Energy Applications
The NI-9242 can be used in renewable-energy measurement systems for monitoring AC voltage signals associated with:
- Solar inverter outputs
- Wind power systems
- Microgrids
- Energy-storage systems
- Distributed generation
- Grid-connected converters
Electric Vehicle Testing
The NI-9242 can support electrical measurement systems used for electric vehicle and charging-equipment validation.
Applications may include:
- AC charging measurements
- EVSE testing
- Onboard charger testing
- Power converter testing
- Motor drive testing
- Energy efficiency analysis
NI-9242 for CompactDAQ
When installed in a compatible CompactDAQ chassis, the NI-9242 can become part of a PC-based modular electrical measurement system.
A CompactDAQ system is suitable for laboratory, validation, production-test, and portable measurement applications.
NI-9242 for CompactRIO
When used with compatible CompactRIO hardware, the NI-9242 can be integrated into embedded and real-time power measurement systems.
CompactRIO is particularly useful when the application requires:
- Standalone operation
- Real-time processing
- Industrial deployment
- FPGA functionality
- Distributed measurement
- Embedded control
NI-9242 vs General-Purpose Analog Input Modules
| Feature | NI-9242 | General Analog Input Module |
|---|---|---|
| Primary Purpose | Power Voltage Measurement | General Sensor / Voltage Acquisition |
| Voltage Level | High AC Voltage | Usually Lower Voltage |
| Three-Phase Measurement | Optimized for 3 Channels | Module Dependent |
| Resolution | 24-Bit | Module Dependent |
| Power Analysis | Well Suited | Application Dependent |
Voltage and Current Measurement System
For complete electrical power measurement, the NI-9242 can be paired with an appropriate current measurement module.
A typical three-phase architecture is:
Three-Phase Voltage → NI-9242
Three-Phase Current → Current Input Module
CompactDAQ / CompactRIO → Synchronized Data Acquisition
Software → Power, Energy and Harmonic Analysis
The exact current module should be selected according to the required current range, sensor type, isolation, bandwidth, and accuracy.
Why Simultaneous Sampling Matters
Power calculations depend on the timing relationship between voltage and current waveforms.
If channels are sampled at different times, phase errors can affect calculated power and power factor.
Simultaneous sampling helps maintain accurate time relationships between acquired waveforms, making it particularly important for:
- Three-phase systems
- Power factor calculations
- Phase-angle measurements
- Harmonic analysis
- Motor and inverter testing
How to Choose a Power Measurement Module
Before selecting the NI-9242, evaluate:
- Maximum line-to-neutral voltage
- Maximum line-to-line voltage
- Number of voltage channels
- AC frequency range
- Required measurement accuracy
- Required bandwidth
- Current measurement requirements
- CompactDAQ or CompactRIO compatibility
- Software compatibility
- Required synchronization
- Electrical safety requirements
- Installation environment
Safety Considerations
The NI-9242 is intended for measurement of potentially hazardous electrical voltages. System designers must follow the applicable NI installation instructions, measurement category ratings, maximum working-voltage limits, wiring requirements, and local electrical safety regulations.
Never select a module based only on nominal system voltage. Verify the exact wiring configuration, transient conditions, measurement category, isolation requirements, and maximum voltage specifications before connecting the NI-9242 to an electrical system.
Software and Programming
The NI-9242 can be integrated with compatible NI hardware and software environments for data acquisition and electrical measurement.
Depending on the selected chassis and application, software can include:
- NI-DAQmx
- LabVIEW
- FlexLogger
- LabVIEW Real-Time
- Compatible NI power measurement software
Software and driver compatibility should always be verified against the exact CompactDAQ or CompactRIO hardware configuration.
Industries
- Power Electronics
- Automotive Testing
- Electric Vehicle Testing
- Renewable Energy
- Industrial Automation
- Electrical Equipment Manufacturing
- Energy Research
- Grid Monitoring
- Motor and Drive Testing
- Research and Development
Applications
Three-Phase Voltage Measurement
Three simultaneous voltage channels make the NI-9242 particularly suitable for measuring three-phase AC systems.
Power Measurement
The NI-9242 can be combined with synchronized current measurement hardware to calculate power, energy, power factor, and related electrical parameters.
Power Quality Analysis
High-resolution waveform acquisition supports analysis of RMS voltage, frequency, phase relationships, harmonics, and waveform distortion.
Motor and Drive Testing
The NI-9242 can acquire three-phase voltage waveforms for motor, inverter, and variable-frequency-drive validation.
Renewable Energy Testing
The module can be used in solar, wind, microgrid, inverter, and energy-storage measurement systems.
Electrical Equipment Validation
The NI-9242 can be incorporated into automated test systems for validating electrical and power electronic equipment.
Recommended Related Products
| NI-9242 | 3-channel, 24-bit C Series voltage input module for high-voltage AC and three-phase power measurements. |
| C Series Current Input Modules | Current measurement modules can be combined with the NI-9242 to create synchronized voltage and current measurement systems. |
| C Series Analog Input Modules | General-purpose analog input modules for voltage, current, sensor, and industrial measurements. |
| CompactDAQ Chassis | Modular USB or Ethernet data acquisition chassis for PC-based electrical measurement and automated testing. |
| CompactRIO Controllers | Real-time embedded controllers for industrial power monitoring, distributed measurement, and advanced control systems. |
Why Choose NI-9242?
- 3 voltage input channels
- Designed for electrical power measurement
- Up to 250 Vrms line-to-neutral measurement
- Up to 400 Vrms line-to-line measurement
- 24-bit resolution
- Simultaneous sampling architecture
- Suitable for three-phase measurements
- Suitable for power and energy analysis
- Compatible with modular C Series systems
- Suitable for CompactDAQ applications
- Suitable for CompactRIO applications
- Useful for motor and inverter testing
- Useful for renewable-energy systems
- Suitable for electrical equipment validation
Frequently Asked Questions
What is the NI-9242?
The NI-9242 is a three-channel C Series voltage input module designed for high-voltage AC and electrical power measurement applications.
How many channels does the NI-9242 have?
The NI-9242 provides three voltage input channels, making it particularly suitable for three-phase electrical measurements.
What is the resolution of the NI-9242?
The NI-9242 provides 24-bit analog-to-digital conversion.
What voltage can the NI-9242 measure?
The module is designed for direct measurements up to approximately 250 Vrms line-to-neutral and 400 Vrms line-to-line, subject to the specified wiring configuration and safety limits.
Can the NI-9242 measure three-phase voltage?
Yes. Its three-channel architecture is specifically well suited to three-phase voltage measurement.
Does the NI-9242 use simultaneous sampling?
Yes. Simultaneous acquisition helps maintain phase relationships between channels, which is important for power and three-phase measurements.
Can the NI-9242 measure current?
No. The NI-9242 is a voltage input module. A compatible current measurement module or appropriate current sensor and input hardware is required for current measurement.
Can the NI-9242 measure power?
The NI-9242 provides voltage waveform measurements. When synchronized with suitable current measurement hardware, the acquired voltage and current data can be used to calculate active power, reactive power, apparent power, power factor, energy, and other electrical parameters.
Can the NI-9242 be used for power quality analysis?
Yes. Its high-resolution simultaneous voltage acquisition makes it suitable for power quality and waveform analysis when used with appropriate hardware and software.
Can the NI-9242 be used for motor testing?
Yes. The module can acquire three-phase voltage waveforms in motor and motor-drive test systems.
Can the NI-9242 be used for inverter testing?
Yes. It can be incorporated into inverter, converter, UPS, renewable-energy, and power-electronics validation systems.
Can the NI-9242 be used with CompactDAQ?
Yes. The NI-9242 can be installed in compatible CompactDAQ hardware for modular PC-based electrical measurement.
Can the NI-9242 be used with CompactRIO?
Yes. It can be used with compatible CompactRIO hardware for embedded, real-time, and distributed electrical measurement applications.
What should I check before purchasing an NI-9242?
Before purchasing the NI-9242, verify the required voltage range, line-to-neutral and line-to-line configuration, number of channels, measurement category, safety requirements, accuracy, bandwidth, chassis compatibility, software compatibility, and whether synchronized current measurement is also required.
Conclusion
The NI-9242 C Series Voltage Input Module provides three simultaneously sampled, 24-bit voltage input channels for electrical power measurement applications. With direct measurement capability up to 250 Vrms line-to-neutral and 400 Vrms line-to-line, it is particularly well suited for three-phase voltage acquisition, power and energy analysis, motor and inverter testing, power quality measurement, renewable-energy systems, and electrical equipment validation using compatible CompactDAQ and CompactRIO platforms.
