What Are the Types of Data Acquisition Systems?

In this article we will learn about the different types of Digital Data Acquisition (DAQ) Systems, describing them with enough detail that you will:

• See what the major variants of digital DAQ systems are
• Learn about how these types differ from each other and why
• Understand how they can be used and where

Introduction

There is a wide variety of types of digital data acquisition systems (DAQ) on the market today. They are available in a variety of form factors, speed, sample rate ranges, signal input types, and many other criteria. DAQ systems cover a very broad range of measurement applications or acquiring and sampling electrical signals, from general-purpose to very specific, which further influences their designs.

Although the focus of this article is on Digital data acquisition systems, there are other kinds of data recorders to mention:

• Digital Data Acquisition
• Data Loggers
• Data Recorders
• Signal Conditioners
• Oscilloscopes
• Spectrum Analyzers
• Vibration Analyzers

Data acquisition system types

We can sort digital data acquisition systems types according to several important criteria:

• Data Acquisition Systems by Form Factor: From small computer-connected modules to stand-alone systems.
• Data acquisition systems by Distributability: Modularity and interoperability of acquisition nodes.
• Data acquisition systems by Speed: How fast they can sample data.
• Data acquisition systems by IP Environmental Protection: The ability to withstand shock, vibration, dust, water, and temperature extremes.
• Data acquisition systems by Control Capabilities: The ability to integrate with real-time control systems.

All data acquisition system types mentioned below offer signal conditioning amplifiers (i.e. signal conditioning circuitry) for sampling and collecting data from all sorts of analog signals and analog sensors such as strain gauge, IEPE, thermocouple, RTD, LVDT, voltage, current, etc.

Learn more about data acquisition systems:

Data Acquisition (DAQ) - The Ultimate Guide [Updated 2024] The complete guide to data acquisition (DAQ). Learn how DAQ systems work and what are the basic elements of modern digital data acquisition systems.

Data Acquisition History - From Strip Chart Recorders to Digital DAQ [UPDATED 2024] History of data acquisition article shows how the industry evolved from early strip chart and tape recorders into the modern digital data acquisition era.

Dewesoft Data Acquisition Technology Explained Find out which are the most important Dewesoft DAQ technologies and learn more about their principle of operation and how they improve the DAQ process.

What Is A Sensor and What Does it Do? Sensors ultimate guide. See what the sensors are. Learn about major sensor types. Understand the importance of sensors in the data acquisition (DAQ).

What Is Signal Conditioning or Signal Conditioner? The complete guide to signal conditioning in data acquisition. Learn what signal conditioning is, types of signal conditioners, and the technology behind.

What Is ADC Converter (Analog-to-Digital Converter)? The ultimate guide to ADC converters (Analog-to-Digital converters). Learn what do they do and which types are best for data acquisition applications.

Types of ADC Converters [Updated 2024] In this article, you will learn about the different types of A/D converters used in data acquisition systems and the basic technology of each type of ADC.

How To Choose the Right Data Acquisition System [UPDATE 2024]? Choosing the right data acquisition system can be a challenge. See our complete guide on choosing the right DAQ system for your measurement application.

Data acquisition systems by form factor

One of the most useful ways to sort the wide range of DAQ systems on the market today is by form factor. DAQ hardware is available in a wide variety of sizes, from those you can hold in your hand to benchtop systems and multi-chassis rack-mounting systems. As you would expect, the smallest systems have fewer channels than larger ones.

DAQ systems are available in a variety of form factors, including:

1. Computer-connected DAQ Modules
2. Stand-alone Data Acquisition Systems (also called Portable data acquisition systems with a built-in computer)
3. Rack-mounting Data Acquisition Systems

Computer-connected data acquisition modules

DAQ systems that connect to the user’s computer are generally less expensive than those with built-in computers. They can also be smaller and lighter by virtue of not having a computer and its related peripherals, such as one or more hard drives, a keyboard, and a display, for example.

Dewesoft makes several popular computer-connected DAQ modules:

Stand-alone or portable data acquisition systems

When a computer is added to a DAQ device, it becomes a stand-alone data acquisition system, meaning that it does not require any additional hardware to perform data recording and analysis as a data acquisition system. These systems usually also have built-in displays and keyboards, although these elements can be connected externally as well. Internal data storage is always included.

Dewesoft makes several popular stand-alone or all-in-one data acquisition systems:

Series	Image	Top Sample Rate/ch	Max Channel Count	Features
MINITAURs		200 kS/s	8 analog 8 counter/encoder 24 digital 1 CAN bus	Very small stand-alone system. The display and keyboard are available as separate options.
SIRIUS R1DB/R2DB		200 kS/s or 1 MS/s	32 analog in 16 counters 48 digital 18 CAN bus	Portable data acquisition systems, configurable with up to two SIRIUS signal conditioning slices . Built-in display, keyboard, and batteries.
SIRIUS R2/R4		200 kS/s or 1 MS/s	64 analog in 32 counters 92 digital 36 CAN bus 32 analog out	Benchtop unit, configurable with 4 SIRIUS signal conditioning cards. The display and keyboard are separate.
SIRIUS R8		200 kS/s or 1 MS/s	128 analog in 64 counters 184 digital 36 CAN bus 64 analog out	High-channel count data acquisition system, configurable with up to 8 SIRIUS cards, a built-in computer, SSD storage, and high-quality signal conditioning.
SIRIUS R8DB		200 kS/s or 1 MS/s	128 analog in 64 counters 184 digital 36 CAN bus	Portable high-channel count display data acquisition system with a built-in computer, SSD storage, and batteries. Configurable with up to 8 SIRIUS signal conditioning cards.
OBSIDIAN		20 kS/s	Up to 8 IOLITE signal conditioning cards.	Embedded data logger with ARM CPU and internal storage for stand-alone operation.

Rack-mounting data acquisition systems

When DAQ systems are going to be installed permanently, for example in a laboratory or test bench, it makes sense to put them in standard 19” rack enclosures. This provides physical protection for the system as well as the cables and is especially useful in high channel count applications.

Dewesoft makes several rack-mounting compatible DAQ systems:

Series	Image	Top Sample Rate/ch	Max Channel Count	Features
IOLITE R12		40 kS/s	Up to 12 slots for analog, and digital I/O	Industrial EtherCAT-compatible data acquisition and control system. Dual EtherCAT data bus with real-time output capability.
SIRIUS R3		200 kS/s or 1 MS/s	32 analog in 16 counters 48 digital 2 CAN bus	Rack-mountable data acquisition system with built-in computer and storage. Configurable with up to 3 SIRIUS signal conditioning cards.
SIRIUS R8		200 kS/s or 1 MS/s	128 analog in 64 counters 184 digital 36 CAN bus 64 analog out	High-channel count data acquisition system, configurable with up to 8 SIRIUS cards, a built-in computer, SSD storage, and high-quality signal conditioning.
SIRIUS R8rt		200 kS/s or 1 MS/s	128 analog in 64 counters 184 digital 36 CAN bus 64 analog out	Same as R8 with additional real-time EtherCAT output for feeding low-latency data to 3rd party controllers.

Distributed data acquisition systems

What does “distributed” mean? Most engineers are familiar with the classic DAQ system that sits on a lab bench. But what about applications that have a wide array of measurement points located some distance from each other? In the past, these applications could only be handled by using multiple DAQ systems and then attempting to merge and synchronize their data together after the testing.

Today there is a new kind of DAQ system. A distributable data acquisition system capable of locating input modules all around a factory or other large area or structure. These DAQ systems are designed to have built-in synchronization across all of the measurement units and input channels. They digitize the signals right at the measuring points, sending back digital data to a central computer, EtherCAT master, or even a central database or cloud database.

The example photo below shows how data acquisition systems are distributed over a large area. This distribution of DAQ systems brings several advantages:

1. The single cable connects DAQ hardware units for power, synchronization, and data.
2. Sensor cable lengths are kept to a minimum since DAQ systems are placed close to them. This removes signal noise and improves signal quality overall.

Dewesoft offers several distributable data acquisition systems:

Data acquisition systems by acquisition speed

Along with accuracy, sampling speed is one of the most important performance characteristics of any measuring system.

Included with all Dewesoft systems, DewesoftX DAQ software supports the full range of sample rates that the hardware allows, from extremely slow speed sampling in the range of minutes or even hours between samples), all the way up to 15 million samples per second (per channel!) with SIRIUS XHS DAQ modules.

Here is a top-level overview of Dewesoft DAQ systems by top acquisition speed:

Slow to medium DAQ systems

Slow to Medium systems (100 S/s to 20 kS/s) are typically found in:

• Process control and machine monitoring applications
• Real-time control, factory automation
• Voltage and current monitoring, power plant tests, relay, and valve tests
• General-purpose testing across every industry
• Civil engineering, structural monitoring

Medium to fast DAQ systems

Medium to Fast systems (200 kS/s) are often found in:

• Noise and vibration (NVH), modal tests, sine processing, structural analysis
• The road load, combustion analysis, cold and hot weather, and vehicle tests of all kinds
• Aerospace and military testing of engines, control surfaces, and wind tunnel tests
• Electromotor tests, elevator

Fast DAQ systems

Fast systems (1 MS/s) are used for:

• Dynamic shock, impact, and crash tests
• Ballistics testing
• Power analysis
• Power quality analysis
• E-mobility

Very fast DAQ systems

Very fast systems (15 MS/s) are used primarily for:

• Transient capture applications
• Impact and crash tests
• Weapons testing
• Power analysis
• Power quality analysis
• E-mobility

Data acquisition systems by environment protection or ruggedness (IP rating)

Rugged data acquisition systems are built to work in very harsh environments. The most important considerations include a wide operating temperature range, the ability to withstand high shock and vibration, and resistance to water, dust, smoke, ice, etc.

Data acquisition systems with control capability

There is a whole new kind of DAQ system available from Dewesoft. So-called data acquisition and real-time control systems. These systems can be used in a real-time control system loop and offer high-speed buffered data acquisition and also stream-reduced data to any 3rd-party EtherCAT controllers with very small latency.

R4rt = 4 SIRIUS slices
R2rt = 2 SIRIUS slices