Wireless Field Instrumentation

Large-scale, reliable, next-generation plant-wide field wireless system

A new architecture for our “Grow” concept

Yokogawa launched the world’s first wireless field products conforming to the ISA100.11a standard in 2010 and has led the business ever since. Now, Yokogawa has released a new, large-scale, reliable, next-generation plant-wide field wireless system.
In developing this system, which forms the core of field digital solutions, Yokogawa has focused on the following three key features.

1. Reliability: reliable high-performance field wireless and redundant technologies
2. Flexibility: flexible architecture that supports the full range, from small to large-scale plants
3. Openness: open ISA100.11a standard that allows third-party field wireless devices to be connected
This new system has been developed in line with Yokogawa’s “Grow” concept of helping customers to grow and enabling ourselves to evolve and continue to offer timely solutions.

 →The individual specifications of products are here：http://www.field-wireless.com/en/products/index.html

Advantages of the next-generationfield wireless system

Although most field wireless systems are currently installed in relatively small areas, demands are rising for increasing the number of monitoring points, covering wider areas, and expanding to process control as well as diagnosis, monitoring, and measurement.
To respond to these demands, Yokogawa has developed a large-scale, reliable, next-generation plant-wide field wireless system, which will manage up to 500* wireless field devices.

Conventional small field wireless systems are mainly installed as additional monitoring tools in areas with a clear line-of-sight such as tank yards and wastewater treatment facilities. Such systems offer only limited advantages such as improved inventory management, reduced regular visual checking, automated environmental measurement, and reduced wiring costs.
In contrast, plant-wide field wireless systems can cover both a large number of measuring points in a small area packed with production equipment where wireless devices are difficult to install, as well as the entire plant. This allows customers to set up wireless devices anywhere in their plants and manage data from those devices to improve plant-wide production efficiency.

Architecture of the large-scale, flexible, field wireless system

Yokogawa has developed the following new products for the new field wireless system:

- YFGW410 field wireless management station
- YFGW510 field wireless access point
- YFGW610 field wireless media converter

Our YFGW710, the existing all-in-one type field wireless integrated gateway, combines all the functions of access points and wireless management, enabling small wireless systems to be easily installed.
In the new architecture, the YFGW510 serves as an access point and forms the wireless backbone network with the YFGW410 field wireless management station.
Therefore, by installing multiple YFGW510 field wireless access points throughout the plant, wireless sub-networks can be built and then connected to each other to create a large-scale, plant-wide field wireless system.
The YFGW510 and YFGW410 can communicate via Ethernet, optical Ethernet, wireless LAN, instrumentation cable communication*, and so forth, allowing flexible installation in plants.

An example of the system configuration is shown below.

Technologies to support a highly reliable field wireless system

YOKOGAWA Field Wireless has excellent receiving efficiency and the feature is high reliability of wireless physical layers（Reliable Radio).The technology enabled the 600m long distance communication with standard antenna if there is no obstacle. The low packet error rate is realized under the environment of multi path in “Pipe Jungle”.

The reliability of network layer is enhanced with the import of new technology. YOKOGAWA proposals are next two technologies.

1. Duocast

Duocast is a redundancy technology for the wireless path specified in the ISA100.11a standard. In the conventional mesh-topology network, if communication is not established in a path, data is then sent via another path. However, this may affect real-time performance because the data is not sent in the same time slot, but in a later time slot even in the same superframe.
On the other hand, Duocast simultaneously sends two identical data in the same time slot, and provided either data is successfully transmitted, real-time performance is maintained. Therefore, Duocast is ideal for ensuring the redundancy of mission-critical wireless paths and helps improve reliability while securing low latency (see the figure below).

　Duocast can overcome failures of either access point as well as errors in a wireless path.

2. Dual wireless backbone network

The network between the YFGW510 and YFGW410 is called a wireless backbone network. Its redundancy is specified by the ISA100.11a standard to improve the reliability of the network and is achieved by the redundant YFGW410 stations. Either of the dual YFGW410 stations can deal with disconnections and errors of the wireless backbone network, and malfunctions of the other YFGW410 (see the figure below).

                           stations, one set to Active and the other to Standby, are connected with each other via a synchronous communication cable. If any trouble in the Active YFGW410 is detected, the functions and data are quickly shifted to the Standby YFGW410 to seamlessly continue communication.

Enhanced Version of Wireless Transmitters

Wireless Differential Pressure/Pressure Transmitter and Wireless Temperature Transmitter have enhanced with the release of Plant Wide Field Wireless System.

The improvement of communication quality with detachable antenna

The detachable antenna type model has released. The antenna extension cable and high-gain antenna* can used with this model. The placement of antenna can be adjusted with the antenna extension cable without change the installation of transmitters.

And the expansion of communication distance becomes possible with high-gain antenna*.
*Subject to the Radio law regulation of each country.

The extension of battery life with low power consumption

The battery life of the detachable antenna type model becomes longer than conventional product with low power consumption. It depends on the condition, from 1.5 times to 2 times of battery life is realized. The examples of the battery life is shown below.

  EJX B Series Wireless Differential Pressure/Pressure Transmitter (Amplifier housing code 8 or 9)

               Update time 10 years at 30 seconds

               Update time 5 years at 10 seconds

  YTA510 Wireless Temperature Transmitter (Amplifier housing code 8 or 9 and low power mode)

               Update time 10 years at 10 seconds

               Update time 8 years at 5 seconds

Summary

Yokogawa has been researching and developing industrial wireless technologies for ten years and has compared a variety of standards, with the following conclusion: in adopting wireless systems in the fields of industrial measurement and control, wireless physical layers must eliminate instability as far as possible (Reliable Radio) and the system must reinforce it.

Among various industrial wireless communication standards, the ISA100 standards were the most suitable for achieving Yokogawa’s policy. Therefore, Yokogawa adopted this standard and released the world’s first ISA100-compliant products in the market in 2010.

Yokogawa has since released various wireless applications while its development engineers have visited over 100 sites worldwide for survey.

The accumulation of such experience as well as the information obtained from many customers have been reflected in the development to make full use of the advantages of the ISA100 standards (ISA100 Full Functional), and to make the role of wireless communication clearer and securer toward Field Digital Innovation.