National Instruments SC Express family of data acquisition modules

National Instruments has announced the company’s first data acquisition modules with integrated signal conditioning for scalable, high-performance measurements on PXI Express.

The SC Express family delivers increased accuracy, high data throughput and synchronisation for measuring strain gauges, bridge-based transducers, thermocouples and high-voltage analog inputs.

PXI Express provides 250 MBps of dedicated bandwidth for each SC Express module in the chassis, which helps engineers increase channel count without compromising sampling rates or data throughput.

The PXIe-4330 24-bit simultaneous bridge input module offers 0.02% accuracy and 25 kSps per channel sample rate for strain, load, force and torque measurements. The module achieves high accuracy with a ratiometric design where the ADC references the excitation voltage. This approach removes the measurement’s dependence on the stability and accuracy of the excitation voltage. In addition, unique delta-sigma ADCs provide both excellent AC performance as well as DC accuracy, while traditional delta-sigma ADCs only offer AC performance.

The module can perform quarter, half and full bridge-based measurements with automatic synchronisation. The included driver software ensures tight synchronisation across multiple modules and chassis with inter-channel skews as low as 5 ppb.

The 8-channel input can scale to a 136-channel system in a single chassis and thousands of channels when synchronising across multiple chassis.

With the PXIe-4353 thermocouple module, engineers can measure temperatures with 0.30°C accuracy on 32 channels. The isothermal terminal block minimises error with a design that optimises thermal conductivity, making it possible for the nearby cold-junction compensation thermistors to accurately measure at the thermocouple junctions.

The module can scale to a 544-channel system in a single chassis and thousands of channels when synchronising across multiple chassis.

The PXIe-4300 high-voltage isolated analog input module is the first analog input module from the company that can measure up to 300 V with simultaneous sampling.

With a 16-bit ADC per channel and a 250 kSps per channel sampling rate, it can stream 4 MBps per module and 68 MBps in a single chassis. This 8-channel analog input module can scale to a 136-channel system in a single chassis and thousands of channels when synchronising across multiple chassis.