Industrial Digital I/O Device for USB – 60 V, Channel-to-Channel Isolated

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BUY ONLINE at ni.com or CALL 800 813 3693 (U.S.)

Isolation

Isolation is a form of built-in signal conditioning that provides an

extended voltage range for direct connectivity to industrial sensors and

actuators. The USB-6525 provides channel-to-channel isolation where

each channel is physically and electrically separated from the others.

Isolation provides three main benefits:

1. Safety from hazardous high voltages and transients

2. Rejection of common-mode voltages

3. Removal of ground loops

Safety from High-Voltage Transients

Isolation electrically separates high-voltage front-end channels from

each other and the low-voltage back end of the USB-6525. Signals

are passed between the two sections of the device using optocouplers.

By separating the two sections, any voltages within the isolation

specifications are prevented from entering the USB bus section or other

channels. Isolation provides protection for the user, data acquisition

system, and measurement data.

Common-Mode Voltage Rejection

A voltage common to both sides of a differential circuit pair is

called common-mode voltage. This phenomenon is typical in noisy

environments containing machinery and inductive loads. The differential

voltage across the circuit pair is the desired signal, whereas the common

voltage signal is the unwanted signal that may have been coupled into

the transmission line. The USB-6525 can measure signals from lines with

signal plus common-mode voltage of up to 60 VDC.

Ground Loop Removal

Ground loops are the most common source of noise in data acquisition

applications. They occur when two connected terminals in a circuit are

at different ground potentials, causing current to flow between the

two points. This additional voltage can cause significant error in the

measurement. When a ground loop exists, the measured voltage is

the sum of the signal voltage and the potential difference that exists

between the signal source ground and the measurement system ground.

This potential is generally not a DC level; therefore, the result is a noisy

measurement system. By offering an isolated floating ground on the

front end, the isolated USB-6525 devices are able to prevent ground

loops from forming.

Software

National Instruments measurement services software, built around

NI-DAQmx driver software, includes intuitive application programming

interfaces, configuration tools, I/O assistants, and other tools designed

to reduce system setup, configuration, and development time.

National Instruments recommends using the latest version of NI-DAQmx

driver software for application development in National Instruments

LabVIEW, LabWindows/CVI, and Measurement Studio. To obtain the

measurement services software speeds up your development with

features including:

• A guide to create fast and accurate measurements with no

programming using DAQ Assistant

• Automatic code generation to create your application in LabVIEW;

LabWindows/CVI; LabVIEW SignalExpress; and Visual Studio .NET,

C/C++/C#, or Visual Basic using Measurement Studio

• Multithreaded streaming technology

• More than 3,000 free software downloads to jump-start your project

• Software configuration of all digital I/O features without hardware

switches/jumpers

• Free LabVIEW SignalExpress LE data-logging software

The USB-6525 is compatible with the following versions (or later) of

NI application software – LabVIEW, LabWindows/CVI, and Measurement

Studio versions 7.x or LabVIEW SignalExpress. You can also use your NI

digital I/O device with ANSI C, Microsoft Visual C++, Visual Basic, and

the Microsoft .NET languages C# and Visual Basic .NET. The USB-6525 is

not compatible with the Traditional NI-DAQ (Legacy) driver.

Ordering Information

NI USB-6525 ..........................................................................779640-01

Includes NI-DAQmx software, LabVIEW SignalExpress LE data-logging software, and

a USB cable.

NI USB-6000 Series Prototyping Accessory ........................779511-01

Includes breadboarding area with cover and strain relief.

BUY NOW!

For complete product specifications, pricing, and accessory

information, call 800 813 3693 (U.S.) or go to ni.com/usb.