National Instruments 781490-01

The National Instruments 781490-01 Sound and Vibration Module, also known as the PXIe-4492, is an advanced 8-input device engineered for precision sound and vibration measurements. This module features 24-bit delta-sigma analog-to-digital converters (ADCs) that deliver a high dynamic range, enabling the detailed acquisition of sound and vibration data. It supports a versatile sampling rate from 100 samples per second to 204.8 kilohertz, with an impressive resolution of less than 181.9 microseconds that ensures consistent and accurate data capture across all channels. Each of the eight channels can be independently configured for either AC or DC coupling, utilizing pseudodifferential input with a resistance of 50 Ω between the negative input and the chassis ground.

The NI 781490-01 incorporates integrated IEPE signal conditioning, providing a constant current of 4 mA to power transducers, such as accelerometers and microphones. This module supports TEDS (Transducer Electronic Data Sheet) in accordance with the IEEE 1451 standard, which streamlines sensor setup and minimizes configuration errors. It automatically adjusts antialiasing filters to match the sampling rate, preserving data integrity and preventing frequency distortion. Performance metrics include an AC coupled gain amplitude accuracy of 0.05 dB at 1 kHz and a DC coupled gain amplitude accuracy of 0.5% within 5 °C of the last self-calibration temperature. The module also incorporates overvoltage protection, allowing the positive terminal to handle inputs up to ±30 V and the negative terminal up to ±5 V.

With compact dimensions of 16 cm x 10 cm, this module is designed to fit seamlessly within a 3U CompactPCI slot, making it suitable for integration into various PXI or PXI Express systems. It supports both analog and digital triggering options, enhancing flexibility for synchronization and data capture in complex test configurations. The 781490-01 is built to operate in diverse environmental conditions, with an operational temperature range of 0 °C to 55 °C and a humidity tolerance of up to 90%. It aligns with multiple international safety and electromagnetic compatibility standards, making it ideal for applications such as noise, vibration, and harshness (NVH) analysis, large-scale microphone arrays, and dynamic structural testing.