National Instruments 785641-01

The National Instruments 785641-01 is a high-performance Strain/Bridge Input Device designed for the FieldDAQ system, identified by the model number FD-11637. This device features eight analog input channels, providing galvanic isolation between each channel and the chassis to ensure reliable data acquisition. With an input range of ±38 mV/V, the 785641-01 is equipped with a 24-bit delta-sigma ADC featuring analog prefiltering for enhanced signal fidelity. It operates in simultaneous sample mode with selectable timebase frequencies of 13.1072 MHz, 12.8 MHz, 12.288 MHz, or 10.24 MHz, achieving a maximum timing accuracy of ±30 ppm. The device supports a flexible data sampling rate, scalable from 500 samples/s to 102.4 ksamples/s.

For network connectivity, the 785641-01 supports both TCP/IP and UDP protocols across multiple ports, including configuration-only ports at HTTP:80, UDP:5353, and others. It includes two internally-switched 8-pin X-coded M12 ports that auto-negotiate Ethernet communication rates of 10/100/1000 Mbps, with a maximum cabling distance of 100 meters per segment and support for up to 15 hops per line. The device operates on an input voltage range of 9 VDC to 30 VDC, with a maximum power consumption of 15 W and heat dissipation of 11 W, all connected through a 5-pin L-coded male M12 connector. The recommended torque for the connector is 0.6 Nm, with a maximum current rating of 10 A at the Power IN/OUT terminals, and it is advisable to use a 16 A slow blow fuse for external overcurrent protection.

Physically, the 785641-01 measures 7.8 inches in length, 3.0 inches in width, and 1.9 inches in height, weighing 1.2 kg. It exhibits high operational durability, functioning effectively in temperatures ranging from -40 °C to 85 °C and withstanding up to 100% relative humidity. For storage, it can be kept in environments from -40 °C to 100 °C and is capable of operation at altitudes of up to 5000 meters. The device is recommended for calibration annually to ensure measurement accuracy.