The National Instruments PCI-8431/8 Serial Interface Device is designed for robust communication in industrial automation applications, supporting RS485 and RS422 standards through eight dedicated ports. This device ensures enhanced protection with optical isolation of up to 2000 V, effectively mitigating issues related to ground loops and high common-mode voltages in noisy environments. The optical isolation between each communication port and the host PC not only safeguards the system against accidental voltage spikes but also promotes safe concurrent operation among peripherals connected to the same interface.

Operating at a typical current of 1.3 A and a maximum of 1.9 A at +5 VDC, the PCI-8431/8 integrates seamlessly into existing setups. It supports four hardware flow control modes, including an advanced 2-wire control mode, which optimizes transmitter and receiver operation across various bus topologies. Users can leverage LabVIEW to easily acquire data from numerous instruments such as serial devices, IEEE 488.2 compatible devices, VXI devices, programmable logic controllers, and modular DAQ systems, significantly enhancing their data analysis capabilities with built-in analysis routines and instrument drivers that streamline software development.

The device features a 68-pin SCSI I/O connector, a maximum baud rate of 3 Mbps, and a FIFO size of 128 bytes, contributing to its overall performance and responsiveness. Compactly designed, it measures 4.2 by 5.7 inches and weighs 85 grams. It operates reliably within a temperature range of 0 to 55 °C and maintains storage capability between -20 to 70 °C, along with humidity resistance of 10 to 90% for operation and 5 to 95% for storage. While National Instruments has announced a mature status for the PCI-8431/8, it remains available for both purchase and repairs through Apex Waves.