Product Overview
The National Instruments NI-9174 is a four slot CompactDAQ chassis with USB connectivity. It is designed to hold up to four C Series I/O modules and to connect them to a host computer through USB. The chassis provides power, communication, and timing resources for the installed modules and supports a compact multi channel measurement system.
The NI-9174 is part of the NI CompactDAQ platform, which is known for modular signal conditioning and quick system assembly. Engineers select C Series modules for the signal types they need, install them in the chassis, and configure the system in software. The chassis handles communication with the host and provides the physical and electrical interface for the modules.
Four Slot Modular I/O
The chassis accepts up to four C Series modules, allowing a mix of analog input, analog output, digital I/O, counter, and communication modules in one system. Module types can be matched to the sensors and actuators in the application, which keeps wiring organized and reduces the number of separate instruments required.
Each module is recognized by the software and can be configured for range, sampling, and scaling. Synchronization across modules is handled through the chassis timing resources, so analog, digital, and counter data can be compared in time. This is important in applications that correlate mechanical, electrical, and thermal measurements.
USB Communication
The NI-9174 uses USB for communication with the host computer. USB is widely available on laptops and desktop computers, so the chassis can be connected without additional network infrastructure. This makes the chassis convenient for bench top measurement, portable test setups, and laboratory work where a dedicated network is not required.
Engineers should validate sustained USB throughput for the planned channel count and sample rate, because host performance and USB bandwidth affect continuous streaming performance. Host power management settings can affect USB device behavior during unattended testing, so these should be reviewed before deployment.
Timing and Synchronization
The chassis provides timing resources for the installed C Series modules and supports synchronization with other NI hardware where the system architecture allows. Hardware timed acquisition and triggering can be used to align measurements with external events. Engineers should document the sample clock source and trigger configuration so that the test sequence can be reproduced.
In systems with multiple chassis, synchronization may require a shared time reference or trigger distribution. Engineers should review the supported synchronization methods for the specific modules and software version. Careful planning reduces timing uncertainty when data from different locations must be compared.
Installation and Environmental Considerations
The NI-9174 is designed for bench top and industrial use. It should be mounted where airflow is adequate and where the operating temperature range is respected. The chassis should be protected from moisture, dust, and excessive vibration beyond its ratings. Cable routing should avoid strain on connectors and should keep signal cables away from high current power conductors.
Proper grounding and shielding help maintain measurement quality. Engineers should follow the module and chassis documentation for shield termination and grounding. In industrial cabinets, DIN rail mounting and organized cable management improve serviceability and reduce the chance of accidental damage during maintenance.
Typical Applications
Portable and bench top multi channel measurement
Laboratory test setups with mixed signal types
Sensor monitoring and data logging
Machine mounted measurement points
CompactDAQ systems with up to four modules
Educational and research measurement systems
The NI-9174 provides a four slot CompactDAQ chassis with USB communication. Its capacity, modular I/O, and USB connectivity make it suitable for compact multi channel measurement applications.
