Deploying from USB to Embedded with C Series Hardware

The NI C Series platform consists of more than 36 measurement modules and seven different chassis for deployment. Configurations can range in size and complexity from simple 4-channel temperature loggers to high channel count, ultrahigh-speed control systems.

 

	Carrier/Chassis	Applications	Recommended Programming Experience
	USB Carrier	Portable, small channel count	None needed
	Wi-Fi/Ethernet Carrier	Remote monitoring, structural monitoring, environmental monitoring, machine condition monitoring	None needed
	NI CompactDAQ	General-purpose mixed sensor DAQ, control, high-speed DAQ, portable system up to 256 channels	None needed
	NI R Series Expansion Chassis	Large advanced test system, deterministic control and acquisition, manufacturing test	Comfortable with NI LabVIEW programming
	NI CompactRIO	In-vehicle logging, rapid control prototyping, advanced control unit, custom design deployment	Comfortable with LabVIEW programming

 

 

 

C Series Modules

 

Overview

Currently, there are more than 36 C Series modules available for different measurements including thermocouple, voltage, RTD, current, resistance, strain, digital (TTL and other), accelerometers, and microphones. Channel counts on the individual modules range from 4 to 32 channels to accommodate a wide range of system requirements. C Series modules combine signal conditioning, connectivity, and data acquisition into a small module for each specific measurement type. These modules can be inserted into any of the C Series family of chassis to create a variety of systems. Creating a mix of channel counts and measurement types within one system is accomplished by selecting the desired modules and installing them into one of several available C Series systems. For this reason, systems built on the C Series platform are highly customizable by the user. 

Connectivity

There are a variety of connector options among all of the C Series modules and some even come with multiple connector options. No terminal blocks are required for any of the modules, thereby eliminating a component and simplifying the overall setup. In some cases standard cables such as BNC, D-Sub, or RJ50 can be used with the modules. The image below shows, from left to right, an 8-channel module with screw terminals, a 4-channel module with BNC connectors, and a 32-channel module with a D-Sub connector.

C Series modules shown with screw terminal, BNC, and D-Sub connectivity

USB Single Module Carrier

Overview

For data acquisition on the market, the USB single module carrier and the NI CompactDAQ chassis both have hardware and software that is easy to set up. The driver, NI-DAQmx, and included software, LabVIEW SignalExpress LE, automatically detect and configure the inserted C Series module. With only a few clicks of the mouse you can log data or view the measurements in a custom display. In addition to the included software, you can program the USB devices with LabVIEW, ANSI C, C#, Visual Basic 6.0, or .NET for a variety of applications. Example programs exist for both graphical and text-based languages to make creating code easier. No external power is required for a USB single module carrier; the USB port on the host computer supplies all the power needed, making this solution ideal for portable applications.

USB single module C Series carrier

 

Tradeoffs

Not all of the C Series family modules are compatible with the single module carrier. A list of compatible modules can be found here: C Series Modules Supported. The "*" next to the model number indicates the module is supported by the single module carrier.

Target User

The target user for a USB single module carrier is someone who wants the lowest cost C Series solution, requires only a few channels, or needs ultimate portability (this system can be connected and powered from a USB port on any laptop based on Windows).

 

Wi-Fi DAQ Devices

Overview

NI Wi-Fi data acquisition (DAQ) devices combine IEEE 802.11 wireless or Ethernet communication, direct sensor connectivity, and the flexibility of LabVIEW software for remote monitoring of electrical, physical, mechanical, and acoustical signals. Wi-Fi DAQ devices can stream data on each channel at more than 50 kS/s with 24 bits of resolution. In addition, built-in NIST-approved 128-bit AES encryption and advanced network authentication methods offer the highest commercially available network security.

Because Wi-Fi DAQ devices use the NI-DAQmx driver, you can use LabVIEW and the DAQ Assistant to quickly and easily develop a measurement application.

For more information on Wi-Fi DAQ, visit ni.com/dataacquisition/wifi.

 

Wi-Fi single module C Series carrier

 

Tradeoffs

Like the USB single module carrier, not all of the C Series modules are supported. A list of compatible modules can be found on the Wi-Fi DAQ FAQ document.

Target user

Wi-Fi DAQ devices are useful for any user who needs to take measurements where cabling is impractical or impossible. Several application areas stand to benefit from wireless or Ethernet connectivity: industrial remote monitoring, structural monitoring, environmental monitoring, and machine condition monitoring.

 

NI CompactDAQ

 

Overview

NI CompactDAQ, NI USB technology, and the NI hardware driver provide an easy way to bring a measurement from a C Series module into a PC/IPC or other machine based on Windows XP. NI CompactDAQ is a chassis that connects to any device or computer running a full Windows OS by USB and can hold up to eight C Series modules. All of the modules are compatible with each other – you can mix and match the modules in the chassis to create a system with your specific channel count and measurement type needs. This platform is programmed with one of the industry standard drivers, NI-DAQmx. This API is easily implemented with a variety of languages including C++, .NET, Visual Basic, and LabVIEW. As an ease-of-use benchmark, most simple data acquisition programs written with NI-DAQmx can be functional within a few minutes, even for a novice LabVIEW programmer.

 

NI CompactDAQ connected to small laptop

 

Tradeoffs

The tradeoffs with the NI CompactDAQ platform include minor limitations on some of the speed ratings of the modules when the chassis is full, as well as a chassis total of 16 channels of analog output. The actual performance of a system can be determined by entering the types of modules and number of channels used in the CompactDAQ System Advisor. For more information about how CompactDAQ works under the hood, see the white paper Three Technologies That Drive USB.

Target User

NI CompactDAQ is ideal for the vast majority of data acquisition systems needed for general-purpose measurements in the lab or test chamber, in the field as a portable unit, or implemented as an I/O unit for a larger machine or processing system. The rugged design and small size of the chassis make it a convenient choice for machine or system builders seeking OTS components with the easiest of implementations that still allow for some system customization. With an included AC adaptor and DC power requirements, the chassis is flexible when it comes to power options. Many systems have been built to run off of a car battery or even a small stack of rechargeable batteries for in-vehicle tests.

 

NI CompactRIO

 

Overview

CompactRIO provides a more flexible and advanced platform for the NI C Series modules with similar mechanical dimensions to that of NI CompactDAQ. Though the implementation is slightly different, a CompactRIO system encompasses all functionality of the CompactDAQ platform and goes far beyond in terms of performance. CompactRIO is a chassis-based platform for C Series modules, but that is where the similarities with NI CompactDAQ end. There is no USB interface to a PC on CompactRIO, and the I/O it is not programmed with NI-DAQmx. With NI CompactRIO, an entire controller/processor is attached to the chassis to form a complete, self-standing, data collecting, processing, and controlling unit. The controller options for the platform are sold separately and vary in specs by hard drive space, processor speed, and RAM. This controller does not run a standard Windows type OS and instead runs a real-time OS. This is important for control applications because it enables time deterministic operations and reliable deployment. This PC type controller is fully programmable by downloading a LabVIEW application to the controller.

 

CompactRIO was designed to operate in rugged environments. A full CompactRIO system consisting of eight C Series modules and a controller is no larger than 92 by 92 by 276 cm, can withstand up to 50g of instantaneous shock, and operates in temperatures ranging from -40 to 70 °C. CompactRIO was designed to provide a fast method of control system prototyping and deployment combining home-built customization and OTS convenience. The image below shows a 4-slot CompactRIO system with four C Series modules inserted. CompactRIO also has an available 8-slot chassis.

 

CompactRIO chassis with four slots and four C Series modules

 

More Than Just a Controller and Modules: FPGA Technology

 

Though the controller provides the main physical difference between NI CompactDAQ and CompactRIO, the biggest technological difference is the field programmable gate array (FPGA) that is built into every CompactRIO chassis. All of the I/O data from the modules first passes through the FPGA in the chassis backplane. With this technology, the more advanced system programmer can customize hardware performance using software flexibility. At anytime, you can download FPGA code to the chassis, which performs calculations and operations that otherwise would be performed by the controller, or not performed at all. Not only does this free up processor load while speeding up performance, but it also gives you the ability to implement features such as custom triggering that would otherwise only be available through custom hardware and circuit design. Any simple digital I/O line can be turned into a counter/timer with FPGA technology. PID control loops can be downloaded to the FPGA rather than the processor, meaning single-point control loops can operate at speeds achieved with custom hardware yet be designed with software flexibility Learn more about FPGA technology from NI at the LabVIEW FPGA homepage.

Tradeoffs

The DAQ Assistant, found in the NI-DAQmx driver and used for the wizard style measurement setup, is not available to help program a CompactRIO chassis. In addition, LabVIEW Real-Time and LabVIEW FPGA modules are needed to program the CompactRIO chassis. While these modules greatly expand the functionality of the system, they do add cost that is not associated with NI CompactDAQ. With these software tools, CompactRIO is not bound by any of the system limitations seen with NI CompactDAQ and, because of the software and FPGA technology from NI, can outperform NI CompactDAQ in all aspects except the USB plug-and-play setup.

Target User

CompactRIO users often require a wide array of data communication standards such as CAN, Ethernet, serial, or other less common protocols. Other key functions include the remote on-board processing that no longer requires a PC for operation. This makes the solution more portable and rugged. Finally, target users often use CompactRIO rather than designing their own special circuitry in house. With no prior embedded development knowledge, a basic to intermediate LabVIEW programmer can program the FPGA for advanced control or design prototyping.

 

R Series Expansion Chassis

 

Overview

For applications that require a combination of PC performance and functionality, high-speed FPGA-based control, and self-contained signal conditioning there is the expansion chassis for R Series boards. R Series boards are multifunction I/O boards for the PC/PXI bus that have an FPGA, similar to the one found in CompactRIO, on board. This chassis is a 4-slot option that, instead of having an onboard controller or USB port, connects by cable to the front end of a PCI/PXI R Series board installed in a desktop PC or PXI chassis. The FPGA is in the board and, like in CompactRIO, all data from the C Series modules pass through the FPGA before moving on to the processor/controller. With this option, you can use the latest PC processing technology in addition to NI FPGA targets. With multiple connectors on an R series board, up to four chassis can be connected to each R Series board – large channel counts can be reached if you are using a PXI chassis with multiple R Series boards.

 

Expansion chassis shown connected to PXI system

 

Tradeoffs

The implementation of a LabVIEW program on a system with R Series expansion chassis is near identical to that of CompactRIO with the LabVIEW FPGA code embedded on the chip and a LabVIEW programming running on the controller/PC. The tradeoffs with CompactRIO are size of hardware, ruggedness, and cost. Although, in return a PXI-based system can have higher channel counts, higher bandwidth, more modules, and a broader range of off-the-shelf communication standards since it is based on commercial PC technology. With the exception of size and ruggedness, a PXI R Series system can do anything a CompactRIO system can do and more.

Target User

Applications for a PXI system range from small and general purpose, to large and highly specialized. PXI systems are often used for manufacturing test because of the reliability of a real-time operating system, high bandwidth, precise synchronization, and wide array of instruments available for the platform. Engineers and scientists that need to combine a large number of measurements with several advanced algorithms should use PXI because of the adoption of the latest in PC processing technology. In addition to advanced computation and manufacturing test systems, PXI systems are often used for high-speed control platforms because of the availability of FPGA devices, signal conditioning from C Series modules, and deterministic timing from the optional real-time operating system.

 

 

 

 

Quick Comparison Table

 

 

 

 

Pricing Information

Find all pricing information online on the product pages or in any of the online system advisors. See specifications, connection diagrams, and accuracy tables for the modules in their individual manuals linked from the product page or by searching for the model number on ni.com/manuals.

CompactDAQ System Advisor

CompactRIO System Advisor

PXI System Advisor

USB Single Module Carrier Model Pages

Wi-Fi DAQ Device Model Pages

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