3 Types of Easy-to-use Remote Data Acquisition Modules

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Date: 2015-01-22

3 Types of Easy-to-use Remote Data Acquisition Modules

3 Types of easy to use remote data acquisition modules

Data acquisition is the process of acquiring real world information from sensors and converting the sample data into numeric values that can be manipulated by a computer. By using remote data acquisition modules, users can monitor and control their applications on central computers based on the information received from remote data acquisition modules, and implement control logic operations like automatically turning on a fan based on the temperature, turning on a pump based on the tank level, etc. Data can be transferred from data loggers or other measuring sensors to the host PC, allowing users access to real time status and trends of the application at a remote site. Remote data acquisition modules are usually compact, light, and easy to use. They support RTD, Thermistor, Thermocouple, Voltage, Current, Strain Gauge, Counter, Frequency, Relay, Digital Input, and Digital Ouptut. They are easy to install and maintain, offering great reliability and flexibility for your control and monitoring projects. There is also less risk of electrical faults and other hazardous conditions compared with other devices.

Data acquisition technology provides tremendous benefits to a wide variety of industries, such as energy monitoring, remote data logging, manufacturing, water treatment, earthquake monitoring, hydrologic applications, etc. Applications can range from monitoring the pressure level of gas pipelines to controlling hundreds of vending machines at different remote sites. The high potential of renewable energy and the need for industrial automation to improve efficiency are driving the growth of global data acquisition (DAQ) market.

Here is a typical data acquisition application diagram. This picture shows a computer program running on a PC connected to an Ethernet switch which is connected to an Ethernet based Thermocouple input and digital output module. The program takes the temperature data and triggers a fan to turn on or off based on the temperature determined by the thermocouple sensor.

Remote data acquisition modules

Depending on what communication protocols they support, easy-to-use remote data acquisition can be categorized into three types: Modbus RTU based DAQ equipment, Modbus TCP based data acquisition devices, and ZigBee wireless data acquisition products.

1. Modbus RTU Based Data Acquisition Modules

Modbus is a serial based communication protocol that is one of the most widely used protocols in industrial automation industries. Modbus was originally published by Modicon (now Schneider Electric) in 1979 for use with its Programmable Logic Controllers. It allows for communication between up to 255 devices connected to the same Modbus RTU network, for example, a system that measures temperature and humidity and communicates the results to a computer. The reason why it is widely used is that it is openly published, royalty-free and easy to deploy and maintain. Modbus is often used to connect a supervisory computer with a remote terminal unit (RTU) in supervisory control and data acquisition (SCADA) systems.

Modbus RTU is an open protocol derived from the Master-slave architecture. It communicates over RS-232 and RS-485, over two copper wires. Modbus RTU is the most common form of Modbus in industrial applications. The ICP DAS USA M-7000 are Modbus RTU based data acquisition remote I/O modules. They are available in a wide variety of Analog and Digital configurations, offering full digital and analog data acquisition capability. For example, the M-7017 is a Modbus RTU remote I/O that has 8 channel voltage input and current input, analog input data acquisition module. It supports input types of ±150mV, ±500mV, ±1V, ±5V, ±10V and ±20mA. It also comes with free EZ Data Logger software for PC based data logging and control applications. M-7017 is used in renewable energy industry to monitor the current and voltage data generated by solar panels and wind turbines. By connecting with a SCADA software on your PC, users can view real time current and voltage data of the power generated at a remote solar power station.

2. Modbus TCP Based Data Acquisition Modules

Modbus TCP is a simple, vendor-neutral communication protocol that supports Ethernet connection. In recent years, Ethernet has been adopted in more and more industrial applications due to its ease of integration, lower cost and high bandwidth. It can be easily integrated with SCADA system by connecting with PLC’s, I/O modules, and gateways via Ethernet. Modbus TCP based data acquisition solutions have brought greater interoperability and faster processing for businesses.

The ICP DAS USA ET-7200 series Modbus TCP based dual Ethernet port data acquisition I/O modules are equipped with 2 Ethernet ports for daisy-chain networking and can easily work with standard Ethernet switches for monitoring and control applications. The daisy-chain typology allows for easier cabling and saves your cost on Ethernet cabling and switches. As remote web-based Ethernet I/O modules, the ET-7200 series also feature a built-in web server which allows you to configure your devices and monitor your systems simply through a regular web browser. Users can create dynamic web pages for I/O monitoring and control without programming or HTML skills. They also come with our free EZ Data Logger Software for remote monitoring and control.

Here’s a real life application that uses ICP DAS ET-7000 Modbus TCP based remote I/Os to set up an emergency warning system. In the emergency warning system of a tunnel, we need to control the cameras and to receive signals from smoke sensors and transmitters. We can build an immediate and control system through the internet with ICP DAS ET-7000 series. They can be linked to devices like cameras, smoke sensors and transmitters. They can send digital output signals to devices like web based LED displays. These displays can help warn drivers about obstructions to keep the roadway smooth and safe. Learn more

3. ZigBee Based Wireless Data Acquisition Devices

With the Internet of Things (IoT) being the next big tech trend, industrial wireless communication opens up many new possibilities for highly flexible and efficient automation solutions. When used in the fields for remote control and maintenance, industrial wireless devices can bring outstanding benefits. ZigBee is a specification based on the IEEE 802.15.4 standard for wireless personal area networks (WPANs). ZigBee lets you easily and cost-effectively add intelligent new features that improve the efficiency, safety, security, reliability and convenience of your applications. They can help users save energy and money, or give them the tools they need to gain control of their homes. It's even possible to help people maintain their independence and allow them to closely monitor their health and fitness.

ZigBee operates in the ISM radio bands, and it defines a general-purpose, inexpensive, self-organizing, mesh network for industrial controls. It can be used in a very wide variety of applications, ranging from building automation to industrial control. ZigBee wireless technology can help with embedded sensing, data collection, smoke and intruder warning, remote control, etc.

ZigBee products can work with data acquisition products for ZigBee I/O Pairing applications where the input of a ZigBee product can wirelessly trigger the output of another module. The ZT-2052-IOP is a ZigBee Alliance based digital input module that can be configured to trigger relay and digital outputs from ZT-2042 Zigbee wireless data acquisition module. ZT-2052-IOP features embedded I/O pairing function, so there is no need for users to use an external controller. The status of each ZT-2052-IOP channel triggers the corresponding remote digital output channels on the ZT-2042 module. The ZT-2052-IOP constantly sends status updates of the digital input channels to the remote ZT-2042 to ensure that the digital output channels are synchronized. It comes with external DIP and rotary switches for easy configuration. ZigBee Alliance based modules with I/O pairing can be used to synchronize digital signals in any environment where wiring is inconvenient.

ZigBee Alliance based Wireless Converters and Data Acquisition Modules are being used in factory automation systems for system status, wireless communication, monitoring and data acquisition. A ZT-2570 host repeater is connected to a laptop computer which runs Indusoft SCADA software. It communicates wirelessly over the zigbee network to ZT-2571 slave converters which are connected to VPD-133 Touch Screen PLC's which operators use to input data. ZT-2060 digital input and relay output and ZT-2053 digital input modules are also in the network for data acquisition. Another ZT-2571 slave converter is connected to serial I/O modules and racks for data acquisition. All the data is gathered on the laptop running SCADA software where users can see the status of the entire factory, generate reports, log data, review alarms and trend reports.

Dora Li
Marketing Coordinator, ICP DAS USA, Inc.
Ph.   (310) 517-9888   |  Fax. (310) 517-0998
Email:  sales@icpdas-usa.com      
Website: www.icpdas-usa.com

ICP DAS USA is a provider of Industrial Data Communication, Automation Control and Test and Measurement products.  We specialize in PLC hardware, Ethernet controllers, distributed I/O modules, Industrial Ethernet Switches and protocol converters.  We provide programming services, training classes and free technical support.

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