The National Instruments cDAQ-9171, part number 781425, is a single slot USB CompactDAQ chassis for C Series modules. It provides a compact platform for connecting one measurement module to a host computer over USB. The chassis is used in portable measurement, bench testing, educational laboratories, and focused data acquisition systems.

The cDAQ-9171 is often used when one measurement function is required, such as voltage input, thermocouple input, current input, digital I O, or counter operations. Its role is straightforward: it connects a compatible C Series module to a host computer over USB and provides the mechanical and electrical interface for measurement.

Single Slot Architecture

The chassis supports one C Series module. This design keeps the system small and cost focused. Engineers can select the module that matches the measurement requirement and use the chassis as a dedicated acquisition interface.

The single slot format supports quick changes between measurement tasks. A module can be replaced when the test requirement changes.

USB Connectivity and Power

The chassis uses USB to communicate with a host computer. The cDAQ-9171 is designed for bus powered operation, which reduces the need for a separate power supply in portable setups. Engineers should verify power requirements for the selected module and the host USB port.

Proper strain relief for the USB cable and sensor wiring helps maintain reliable operation.

C Series Module Compatibility

The cDAQ-9171 works with compatible C Series modules. Module selection should consider signal range, isolation, resolution, sampling rate, and connector type. The chassis provides the USB and mechanical interface, while the module defines measurement performance.

Software and System Integration

The chassis is designed to work with NI data acquisition software and standard application development environments. Engineers can configure channels, acquire data, log results, and build user interfaces.

For small systems, the cDAQ-9171 can serve as a dedicated acquisition node connected to a laptop or desktop computer.

Applications

The cDAQ-9171 is suitable for benchtop validation, sensor characterization, educational experiments, and portable diagnostics. In a sensor characterization setup, the chassis can hold a voltage or temperature module while the host computer records response data.

Installation and Maintenance

Installation requires connecting the chassis to a compatible C Series module, attaching the USB cable, and verifying software recognition. The chassis should be placed in a location that avoids excessive heat, moisture, and mechanical stress.

Maintenance includes checking USB connections, inspecting module seating, and confirming software configuration. Documentation of module type and channel configuration helps maintain repeatability.

Summary

The National Instruments cDAQ-9171 CompactDAQ Chassis 781425 provides a single slot platform for C Series measurement modules. It combines USB connectivity, bus powered operation, and a small footprint for portable and focused data acquisition. The cDAQ-9171 is a practical choice for simple and flexible measurement systems.