National Instruments 777687-14 Universal Strain Terminal Block 

National Instruments part number 777687-14 is an identifying part number for the SCXI-1314 Universal Strain Terminal Block. The NI 777687-14 is designed for use with the SCXI-1520 module. This setup enables easy connection of strain gauges via screw terminals. The terminal block features 88 screw terminals, organized into eight groups of 11 terminals each. Each group corresponds to a channel on the SCXI-1520 module, and every channel input has screw terminals that connect to the inputs. 

Additionally, there are two precision 100 kΩ shunt calibration resistors and a precision quarter-bridge completion resistor on the 777687-14. The SCXI-1520 module uses relays to switch the resistors in and out of the input circuit for shunt calibration and quarter-bridge completion. The quarter-bridge completion resistor is set to a default value of 350 Ω, suitable for use with a 350 Ω strain gauge. These resistors are placed in sockets on the terminal block, allowing users to easily replace them with resistors suited to their specific strain gauge needs. For applications requiring a 120 Ω strain gauge, eight 120 Ω resistors can be used. 

The part number 777687-14 operates with the NIDAQmx driver software, compatible with LabVIEW, LabWindows/CVI, and Measurement Studio. To install this Terminal Block, you will need several items. These include an SCXI chassis, the SCXI-1520 module, eight precision 120 Ω resistors (if using quarter-bridge completion circuits), a wire insulation stripper, a wire cutter, long-nose pliers, a 1/8 in. flathead screwdriver, Number 1 and 2 Philips-head screwdrivers, and the Installation Guide/User Manuals.

National Instruments has declared obsolete status for the 777687-14 terminal block, however, it is still available for purchase and repairs at Apex Waves.