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The convenience and reliability of Ethernet technology is as familiar to most as USB. The new NI cDAQ-918x chassis expand the NI CompactDAQ platform to include Ethernet for extending the reach of PC-based data acquisition to remote or distributed sensor and electrical measurements. The cDAQ-918x Ethernet chassis feature the same specifications as the NI cDAQ-917x USB chassis with one significant exception: cable length.
Table of Contents
- Ethernet Data Acquisition
- Zero Configuration Networking
- Mixed Measurements with Multiple Timing Engines
- NI Signal Streaming over TCP/IP
- One Driver, Many Buses
- Buy Now
Figure 1. The NI cDAQ-918x Gigabit Ethernet chassis expand the NI CompactDAQ platform to remote or distributed measurement applications.
Ethernet Data Acquisition
Ethernet offers two advantages over other common PC peripheral buses: long cabling lengths and network infrastructure. Ethernet is ideal for taking measurements at distances beyond the 5 m limit of a USB cable. A single CAT 5E cable can reach 100 m before needing a switch or router to carry the signal farther. Furthermore, many IT departments have standardized on Gigabit Ethernet (IEEE 802.3ab) as the foundation of their corporate networks. With NI CompactDAQ, you can now take advantage of that existing infrastructure and additional network bandwidth for your remote or distributed measurement applications. One host computer can manage multiple test stations within the same facility or across multiple sites. In fact, as long as an IP network connection exists, you can access an NI CompactDAQ system from anywhere in the world.
Figure 2. You can access an NI CompactDAQ Ethernet chassis from anywhere with an IP network connection.
Zero Configuration Networking
Traditionally, the process of network configuration and administration has not been for the timid. To make networking technology more accessible to the non-IT professional, NI CompactDAQ Ethernet chassis uses the Zero Configuration Networking (Zeroconf) standard. Zeroconf is a collection of three technologies: link-local addressing, multicast DNS, and DNS Service Discovery.
- Link-local addressing provides automatic IP addressing in the absence of a DHCP server.
- Multicast DNS (mDNS) delivers automatic resolution and distribution of hostnames in the absence of a DNS server.
- DNS Service Discovery (DNS-SD) offers automatic discovery of network services such as printing or data acquisition.
With Zeroconf technology, you can plug an NI CompactDAQ system directly into your computer or local subnet, and it appears automatically in the NI Measurement & Automation Explorer (MAX) configuration utility without any network setup or configuration.
In addition, a new Web configuration interface built into the firmware of the cDAQ-9188 helps you manage your system through a Web browser without installing any software on your host machine. The utility is built on Microsoft Silverlight, a new technology that provides a seamless user experience between the Web and the desktop. You see the same configuration screen whether you use a Web browser or MAX.
Figure 3. With the embedded Web server on the cDAQ-918x chassis, you can remotely configure your NI CompactDAQ system from a Web browser or from MAX.
Watch a video demonstration of the Web-Based Configuration for NI CompactDAQ
Mixed Measurements with Multiple Timing Engines
NI CompactDAQ Ethernet systems provide the flexibility of measuring low-speed DC data and high-speed dynamic signals in the same instrument. The chassis backplane includes the NI-STC3 timing and synchronization controller, which is capable of managing up to seven hardware-timed data streams for multiple analog I/O, digital I/O, and counter I/O measurement tasks. Combined with your choice of more than 50 different NI C Series I/O modules, this technology enables the NI CompactDAQ platform to provide a broad spectrum of I/O capabilities for mixed-measurement systems. You can install a thermocouple module next to an accelerometer module and acquire from both modules simultaneously at different rates because each can synchronize to a separate timing engine. This alleviates the need to decimate or parse lower-speed data from the higher-speed data.
Figure 4. More than 50 different sensor-specific NI C Series I/O modules are available for creating custom, mixed-measurement systems.
Watch the NI CompactDAQ Ethernet chassis out-of-box video
NI Signal Streaming over TCP/IP
To take advantage of the 1,000 Mbit/s of bandwidth on a Gigabit Ethernet network, NI CompactDAQ chassis implement a TCP/IP version of the same patented NI Signal Streaming technology found in high-performance NI USB data acquisition (DAQ) products. With this technology, new high-speed C Series modules, such as the NI 9223, can continuously acquire up to 1 MS/s of simultaneous 16-bit data on each of four channels. Using a sophisticated software architecture, NI-DAQmx driver software maintains a double-buffered transfer mechanism between the chassis and host computer capable of sustaining several bidirectional continuous waveforms. At the same time, the driver monitors the state of the network to adjust for unexpected delays or temporary interruptions due to network traffic. All of this is abstracted from the user, so you can focus on the measurement application and not the network.
Figure 5. Patented NI Signal Streaming technology enables parallel streaming of high-speed, bidirectional data from multiple measurement tasks over TCP/IP.
Find out more about NI CompactDAQ technologies
One Driver, Many Buses
Recognizing the diversity of measurement applications, NI approaches programmatic data acquisition independent of specific PC bus technologies. You can use the same NI-DAQmx driver software to communicate with NI data acquisition hardware across PCI, PCI Express, PXI, PXI Express, USB, Ethernet, and Wi-Fi. You can use an application developed for an NI CompactDAQ USB system with an NI CompactDAQ Ethernet system without making any changes to your software. Furthermore, the NI-DAQmx API is consistent across multiple programming platforms, so you can develop an application for NI CompactDAQ in NI LabVIEW, C/C++, C#, or Microsoft Visual Basic .NET.
Figure 6. NI-DAQmx driver software abstracts the complexity of specific hardware interfaces for a consistent API across different data acquisition buses.
Read more about using NI CompactDAQ with NI LabVIEW
Buy Now
Configure your NI CompactDAQ Ethernet system with the NI CompactDAQ Advisor.
View a pre-configured NI CompactDAQ Multifunction System.
View pricing and purchasing information on the NI cDAQ-918x Ethernet chassis product pages.
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