Using NI CompactDAQ Controllers

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1 Using NI CompactDAQ Controllers When architecting a system with an NI CompactDAQ controller, there are many factors to consider. For example, developing and deploying a Windows-based system is going to be a different experience than using the NI LabVIEW Real-Time Module. Beyond development and deployment considerations, you must also decide how to communicate with the system and store your data. Development First, consider how you will interact with your controller. The experience will be different depending on the OS, and whether you want to connect directly or remotely. The development and deployment stages of your application will also offer different experiences. In the development stage, you design, test, debug, and validate your code. As such, you will need to regularly interact with your hardware and software. Windows When developing a Windows-based system, you can connect to it directly or through a remote connection. In both configurations, you will need to use NI LabVIEW 2014 or later and NI- DAQmx 14.1 or later. Direct Connection NI CompactDAQ controllers with Windows operate just like a standard PC. You can simply connect a mouse, keyboard, and monitor and you are ready to begin programming. Remote Connection Alternatively, you can use the Windows Remote Desktop Connection to remotely connect to NI CompactDAQ through a network connection. The environment gives you the same look and feel as the local connection, but without the need to physically plug in peripherals like with a direct connection. LabVIEW Real-Time You need a remote host computer to develop a LabVIEW Real-Time application. The host can be any Windows computer with LabVIEW and LabVIEW Real-Time installed. After the PC and NI CompactDAQ are networked together, you can deploy your code as often as you need for testing and debugging. National Instruments. All rights reserved. LabVIEW, National Instruments, NI, ni.com, the National Instruments corporate logo, and the Eagle logo are trademarks of National Instruments. See ni.com/trademarks for other NI trademarks. Other product and company names are trademarks or trade names of their respective companies. For patents covering National Instruments products, refer to the appropriate location: Help>>patents in your software, the patents.txt file on your CD, or ni.com/patents.

2 Networking Even though NI CompactDAQ controllers can fully operate on their own, you may need to remotely develop, control, monitor, and retrieve data. A networked setup could be as simple as a host computer directly connected to NI CompactDAQ, or a computer interacting with multiple chassis within the same facility or even across multiple sites. As long as a network connection exists, you can access NI CompactDAQ from anywhere in the world. Figure 1. NI CompactDAQ controllers can network via Ethernet, wireless, and cellular connections to other systems like a host computer or a mobile device. Ethernet Hardwired Ethernet network connections are generally considered fast, reliable, and simple. NI CompactDAQ controllers feature two Gigabit Ethernet ports that give you the ability to directly connect. A single CAT 5E Ethernet cable can reach up to 100 meters before needing a switch or router to carry the signal farther. With Ethernet, you have the option of directly connecting a computer to an NI CompactDAQ system, connecting through a router, or using an existing network. The disadvantage to Ethernet connections is that they require physical wiring, which may not be feasible in certain environments. Wireless The main benefit of wireless technology is the ability to minimize the use of wires and cables. Depending on the nature of the application and the environment, physical wiring can be expensive, inconvenient, or even impossible. Some implementations include moving platforms, mobile applications (for example, vehicles or cranes), and structures that complicate wiring installation. You can use a wireless access point to connect an NI CompactDAQ controller to a wireless network. A wireless access point acts as a bridge between wired and wireless connections by converting the wireless signal into Ethernet that can be plugged into the chassis. National Instruments sells the MOXA AWK-3121 as an option to work with NI CompactDAQ controllers. Wireless networking is generally slower than Ethernet, not always as reliable, and can be more complicated to implement. 3G Cellular Wireless Access Point 2

3 If you don t have access to a wired or wireless network, consider using the S.E.A. GXXX 3G Mobile HSPA module. The module plugs into the NI CompactDAQ controller, and, similarly to the wireless access point, acts as a bridge between cellular networks and the Gigabit Ethernet port found on the system. You can access the system anywhere there is a cellular data connection, though carrier data rates apply. Data Streaming There are different file types and storage locations to choose from depending on your application requirements. File Types For embedded measurement applications, NI recommends one of two file format types: binary or Technical Data Management Streaming (TDMS). Binary Binary files store data as raw values, as opposed to a text file, which stores data as userreadable ASCIIbased text characters. Although binary files are not directly readable by the user, they do offer a major advantage in throughput. Data can be stored and retrieved in binary format much faster than in text format. TDMS A TDMS file is an open binary file format that NI introduced as a result of the deficiencies of other data storage options commonly used in test and measurement applications. The TDMS file format is an easily exchangeable, inherently structured, high-speed-streaming-capable file format that, when combined with the other technologies in the NI TDM solution, becomes quickly searchable without the need for complicated and expensive database design, architecture, or maintenance. Storage Location Next, you should consider where you are going to store your data as there are internal, external, and network storage options. Internal and External Storage NI CompactDAQ controllers include options for internal and removable SD storage.. You also have the capability of connecting additional external storage devices through the built-in USB ports. Table 1 outlines the various options. 3

4 Medium Location Throughput 1 Capacity Pros Cons Removable Removable 14 MB/s 32 GB Removable Slower SDHC Swappable Throughput (9132/34 Only) Easy data access cfast Card Internal 25 MB/s 32 GB Onboard Difficulty (9138/39 Fastest retrieving data Only) throughput Limited disk space USB External 2 MB/s Up to Removable Slow throughput Thumb 64 GB Swappable Drive Price per GB External External 16 MB/s Up to 3 Fast throughput Susceptible to USB HDD TB Removable vibration Swappable Larger Capacity External External 16 MB/s Up to Fast throughput Smaller capacity USB SSD 512 GB Removable versus HDD Swappable Price per GB No moving parts Extended temperature range 1 Approximate throughput that varies with transfer methods used Table 1. Choose from a variety of options for internal and external storage. Network Storage You could also consider network storage, which can offer a larger amount of storage space and offload data to a location where it can be easily backed up and accessed by multiple users. This requires a reliable network connection, and the total throughput depends on network connection and the access speeds of your storage location. You can stream to a network storage site or a host computer. You also have the option of using a cloud service like the NI Technical Data Cloud. Deployment Once you have developed and debugged your code, you will be ready to deploy your measurement system. Much like the development phase, you have different options for interacting with your deployed system. In the deployment phase, your main objectives are to configure your tests, as well as to monitor, retrieve, and process your data. Windows With Windows, you have the option to replace a monitor with a more portable touch screen or use the full functionality of a touch panel PC. Direct or Remote Connection 4

5 Similar to the development phase, you can connect a monitor, keyboard, and mouse directly to NI CompactDAQ to control it. You also still have the opportunity to remotely connect to the system through Windows Remote Desktop Connection. Touch Panel Monitor You can replace the functionality of a monitor, keyboard, and mouse with a touch panel monitor, which gives you the ability to operate the software directly by touch. While a touch panel is not ideal for many small changes, it is useful for tweaking a few parameters on the fly. Touch Panel PC You also have the option to remotely monitor and control an NI CompactDAQ controller from a touch panel PC. A touch panel PC is a separate computer that can interact with the system through a network connection LabVIEW-Real Time When running LabVIEW Real-Time, you can use a touch panel PC much in the same way that you would with a Windows system, which gives you the ability to control and monitor your application through a network connection. Mobile Devices You can also choose to integrate mobile devices to control and display your data. With the NI Data Dashboard, you can create custom views of LabVIEW applications to display charts, gauges, textboxes, and LEDs. Data Dashboard is available for ios and the Android OS through their respective app stores. 5