USB Data Acquisition Frequently Asked Questions (FAQ)

Overview

The following are the most frequently asked questions about NI USB data acquisition (DAQ) devices.

Contents

On which OSs can my DAQ device run?

NI DAQ products are compatible with most common OSs, depending on the device.Visit the NI-DAQ driver support page for more information.

What performance level can USB  DAQ devices offer?

USB DAQ technologies, such as NI Signal Streaming, help you achieve unprecedented performance over USB. Total throughput is system- and device-dependent, but USB 2.0, devices such as X Series DAQ or CompactDAQ can sustain up to 32 MB/s of data throughput. With USB 3.0, the cDAQ-9179 can sustain data transfer rates of more than 250 MB/s.

  • High-performance X Series devices for USB can stream data at up to 2 MS/s for analog input and up to 2.8 MS/s for analog output
  • Simultaneous sampling USB X Series devices can acquire data from all eight analog inputs at 2 MS/s per channel on select PCs (16 MS/s or 32 MB/s)
  • CompactDAQ delivers a modular platform with up to 14 slots for I/O and analog input module throughput up to 1 MS/s per channel.

How far away from my computer can I place my USB DAQ device?

The USB specification limits the distance between your computer and a device or hub to 5m.

For distances further than 5m, NI recommends that you use Ethernet or wireless DAQ devices.

What USB standards are NI USB DAQ devices compatible with?

All NI USB DAQ devices are compatible with USB 2.0. Three speed classifications exist in USB 2.0: low-speed (1.5 Mb/s transfer rate), full-speed (12 Mb/s), and Hi-Speed (480 Mb/s). NI USB DAQ devices use both the Hi-Speed and full-speed modes of operation. Full-speed devices compatible with USB 2.0 also work with USB 1.1 hosts without any decrease in transfer rate. However, USB 2.0 devices are limited in speed if used with a USB 1.1 host or a USB 1.1 hub.


CompactDAQ offers support for USB 3.0 with the cDAQ-9179 14-slot USB chassis. The USB 3.0 standard operates in SuperSpeed mode at 5 Gb/s transfer rate. The cDAQ-9179 is also compatible with USB 2.0 and USB 1.1, but speeds will be limited by the data transfer rates of the host or hub.

Can USB DAQ products be used in industrial environments?

High data throughput; ease of use; reliable communication; and availability on industrial PCs, laptops, and industrial human machine interfaces (HMIs) have made USB an attractive bus technology for industrial use. Several NI products also provide built-in isolation to protect plant assets, the DAQ system, the host PC, and the user from hazardous voltages. They also offer panel and DIN-rail mounting options, along with strain relief, to prevent accidental disconnection of a USB cable.

Which certifications are provided with the USB DAQ devices?

NI products comply with the applicable international requirements for product safety, electromagnetic compatibility (EMC), hazardous locations, marine, RoHS, and quality. Refer to the NI product certification web page for product-specific certification information.

Is there a way to prevent the USB cable from disconnecting from my laptop?

An accessory is available to prevent any accidental disconnection of the USB cable from a laptop. Refer to Strain Relief Accessory.

USB X Series devices and CompactDAQ include USB cables with locking thumbscrews for securing the connection of the USB cable to the DAQ device.

Can I use smart TEDS sensors with NI USB DAQ devices?

Combine USB DAQ and smart transducer electronic data sheet (TEDS) sensors to achieve the ultimate in simple setup: a plug-and-play DAQ system. NI has worked with more than 20 sensor vendors to create Sensors Plug&Play hardware and software to parse and interpret the data from smart TEDS sensors. There are several ways that you can combine smart TEDS sensors, Sensors Plug&Play hardware and software, and USB DAQ to create a plug-and-play DAQ system:

  1. Use a CompactDAQ chassis with one of the following modules: NI 9219, NI 9233, NI 9234, and NI 9237. Connect the TEDS sensor to the module and use NI-DAQmx measurement services software to interpret and apply the TEDS data.
  2. Use the SCXI-1600 USB DAQ and control module for SCXI along with the SCXI-1520 bridge sensor input module and the SCXI-1314T TEDS terminal block. Connect any bridge-based TEDS sensor to the terminal block and use NI-DAQmx measurement services software to interpret and apply the TEDS data.
    Note: SCXI is now obsolete and is no longer manufactured or available for purchase and support services are also no longer available.

What is the NI ready-to-run data-logging software and how do I use it?

Windows Users

All NI USB DAQ devices supported by NI-DAQmx has access to the free companion software known as DAQExpress™.  Visit the DAQExpress web page to learn more about the capabilities of this software. Another ready-to-run data-logging software on offer is FlexLogger™, which is ideal for those who wish to accomplish quick and easy data logging tasks. 

For software systems prior to LabVIEW 2015, there is also SignalExpress which can be used in place of DAQExpress and FlexLogger.

Mac OS/Linux OS Users

On Mac OS and Linux OS, a subset of NI DAQ products is supported by NI-DAQmx Base driver software. This software includes ready-to-run data-logging software to help you begin taking measurements quickly.

 
NI DAQExpress (left) and FlexLogger (Right)

 

Do I need to buy a separate terminal block and cable to use my USB DAQ device?

Most NI USB DAQ devices feature built-in signal connectivity for your convenience, including screw and BNC connectors. See device model pages for more details.

Do any USB DAQ devices have isolation?

Yes, several C Series modules include some level of isolation: bank isolation, channel-to-earth ground isolation, or channel-to-channel isolation. In addition, there are several bus-powered multifunction USB devices that feature isolation, including the USB-6215, USB-6216, and USB-6218.

Measurement and control applications often involve environments with hazardous voltages, transient signals, common-mode voltages, and fluctuating ground potentials capable of damaging measurement systems and ruining measurement accuracy. Isolation electrically separates sensor signals from the measurement system’s low-voltage backplane and offers many benefits including projection of equipment and user, improved noise immunity, ground loop removal, and increased common-mode voltage rejection.

NI products are UL- and CE-certified, and all isolated devices are rated based on rigorous tests for their respective measurement categories. NI isolated DAQ products meet both spacing requirements and high-potential withstand tests required for proper certification.

Was this information helpful?

Yes

No