Simple. Complete. Ethernet Data Acquisition

The NI ENET-9000 series includes measurement quality data acquisition devices that were designed to make taking distributed measurements over standard Ethernet simple. More than five devices are available to take measurements of thermocouples, voltage, resistant temperature detectors (RTDs), strain gages, current, resistance, accelerometers, microphones, load cells, and more. Though the setup and implementation of these devices is simple, the performance of the ENET-9000 series is impressive. The ENET-9000 devices, see figure 1, can constantly stream 24-bit data at sampling rates of more than 200 kS/s, which is needed to capture high-speed transients or harmonics often found in acoustical, vibration, or dynamic strain testing. This performance is obtained without deep onboard memory, meaning your data retrieval is constant and only limited by the rate of your network. With the provided flexible software options – the data-logging software package NI LabVIEW SignalExpress and full programming support for LabVIEW, ANSI C, C#, Visual Studio, and .NET – you can develop a remote monitoring or test application using one or several ENET-9000 devices.

Figure 1. ENET-9000 Ethernet data acquisition device

Measure Remotely with Ethernet

Ethernet is ideal for taking measurements at distances beyond 5 m. A single Ethernet cable can extend 100 m before needing a hub, switch, or repeater. This distance, in combination with a large install base of networks in homes, labs, offices, and manufacturing facilities make the ENET-9000 an ideal choice for delivering NI measurement quality to remote locations. Though network performance is highly dependent on the number of networked devices, 100 Mb Ethernet (the most common at this point in time) can accommodate multiple ENET-9000 devices running at full speed. A 100 Mb network has a theoretical bandwidth of 12.5 MB/s per drop. As an example, the ENET-9234 needs a little more than 0.6 MB/s of bandwidth to constantly stream 200 kS/s of 24-bit data over Ethernet. No special gateways or interface cards are required to use an ENET-9000 device; a simple gateway found at a local electronics store will work. For more reliable, rugged Ethernet switches, NI offers a collection of switches and wireless access points. Learn more about those devices from the Ethernet Switches and Wireless Access Points homepage.

Integrate Ethernet Devices into an Existing System with LabVIEW

Test and measurement systems range in size from a few channels to a few thousand channels and the ENET-9000 devices can be the whole system, or the distributed component of a larger system. You can use many different bus technologies, such as PXI, PCI, USB, Ethernet, and Wi-Fi, for data acquisition. Each bus brings capabilities to the system and many times it is advantageous to use multiple busses for a single test system. PXI Express and PCI Express have the highest bandwidth available, USB has the easiest device setup and configuration, Ethernet is best for distributed systems, and Wi-Fi eliminates all problems associated with wires. Using LabVIEW and the NI-DAQmx API for the ENET-9000 device gives you complete system integration whether the other components are NI devices or manufactured by a third party. Because LabVIEW is a development environment, one user interface can include data from multiple devices, buses, and manufacturers. Figure 2 shows a single LabVIEW program, or virtual instrument (VI), that can acquire data from an Ethernet device, a USB device, and a PXI-based device. Each NI device has an associated DAQ Assistant and thus the hardware differences of the devices are abstracted from the programming experience.

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Figure 2. LabVIEW code for a multi-bus data acquisition system

Detect, Configure, and Acquire within Minutes with the ENET-9000

The ENET-9000 devices are shipped with the test and configuration application, Measurement & Automation Explorer (MAX). This is the same utility (Figure 3) that all other NI hardware uses, so all of your devices, regardless of data bus used, show up in the same place. The ENET-9000 is configured the same way as any other networked device such as laptops or gaming systems. The ENET-9000 can operate with either a static IP address or one dynamically assigned from a DHCP server. Once your system detects the device, you can remotely change the configuration settings, test the connected sensors, or begin programming your system with the NI-DAQmx driver just as you would any other NI data acquisition (DAQ) system.

Figure 3. MAX configuration utility with multiple devices

NI-DAQmx and LabVIEW, the National Instruments Data Acquisition Difference

There are two main advantages when developing a system with LabVIEW and NI-DAQmx: development time and flexibility. NI-DAQmx is the API that is shipped with the ENET-9000, and all other NI DAQ devices. With this set of drivers, you can program for many text-based programming languages including ANSI C, C#, Visual Studio, and .NET, but when programmed with the LabVIEW graphical development environment you have access to the DAQ Assistant (Figure 4), a graphical wizard-style programming interface that guides you through acquiring data with your NI device. This single node, known as an Express Virtual Instrument, or Express VI, significantly reduces the development of your data acquisition code by turning your configuration settings into running code. In addition to the DAQ Assistant, LabVIEW has hundreds of built in functions for analysis, alarming, reporting, and file I/O that further reduce your data acquisition system’s development time. Because you are developing with LabVIEW programming, the functionality of your system is not limited. As your project grows or changes, you can modify your code to meet the new requirements. LabVIEW also helps to eliminate the need for multiple software programs for a single process. There are thousands of third-party devices on the market that have drivers written for LabVIEW. You can easily integrate these devices into any LabVIEW program. For those devices that do not have a full driver, you can use a development API to integrate the new hardware device with your existing system based on LabVIEW.

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Figure 4. The DAQ Assistant configuration screen for thermocouples

I/O for Any Application with C Series

The ENET-9000 series of devices is a component of the NI C Series hardware family. The C series hardware family includes modules, chassis, and carriers designed for high-speed data acquisition and deterministic control on the benchtop, in the field, on the production line, or embedded in larger machines. More than 40 modules are available for measurements such as temperature, pressure, voltage, acceleration, current, resistance, strain, and more. Chassis and carriers are available for PC communication over Ethernet, Wi-Fi, USB, as well as chassis with onboard controllers and storage for embedded machine design or rugged data acquisition systems with local storage. Figure 5 displays an image of an 8 slot USB chassis, an 8 slot chassis with embedded controller and hard disk, and a bus-powered USB carrier for a portable laptop based system. For more information on C Series hardware, or for a list of compatible modules, see the compatibility table.

Figure 5. C Series modules shown in different chassis and carriers

Frequently Asked Questions (FAQs)

These modules look like the same ones for NI CompactDAQ and CompactRIO. Are they interchangeable?

The modules used in the ENET-9000 devices are the exact same as modules that have been on the market from NI for many years. At the time of release, five of the modules are supported on the ENET carrier. If you already own some of these modules, you can use them in an ENET-9163 carrier for which there is a separate kit. NI-DAQmx 8.8 or later is required for the ENET-9000 devices.

Where can I see which modules are supported by which C Series chassis and carriers?

There is a compatibility chart online: Click here

What comes in the box?

If you order the ENET-9000 devices as a kit, they will contain an ENET-9163 Ethernet carrier, a C Series module, and the following accessories:

• Power adapter

• 4 pin connector for trigger inputs

• Antiskid rubber feet for desktop use

• NI-DAQmx driver kit

• Getting started with NI-DAQmx

• Hardware user manuals for carrier and module

Can I order the carrier separately if I already own modules?

Yes. The NI ENET-9163 is sold separately. Please check the online support guide to see if your modules are compatible with the ENET-9163 carrier.

What is the best way to order an ENET-9000 device?

There are online model pages for all of the kits as well as the ENET-9163 carrier. There is also an advisor that quotes multiple modules and carriers in one online configuration.

How fast can the ENET-9000 devices acquire data?

Under normal network conditions, the ENET-9000 devices constantly stream all data back to the PC without needing to buffer any data on the device side.

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