HART Maximization

It wasn't until we wanted to know who was calling on the telephone that we decided we needed caller ID. That data point was on the wire with the voice all along, we just didn't have a real need to see the information. With that in mind, look at your plant and consider what you already have installed that you may not be using to its full potential.

By Ron Helson July 1, 2005

HART offers two simultaneous communication channels—a 4-20 mA channel and a digital two-way communication channel for device status, diagnostics, and alerts.

It wasn’t until we wanted to know who was calling on the telephone that we decided we needed caller ID. That data point was on the wire with the voice all along, we just didn’t have a real need to see the information. With that in mind, look at your plant and consider what you already have installed that you may not be using to its full potential. The answer will likely be HART Communication.

HART Communication is installed in more than 15 million process devices worldwide and included in 70% of all smart process measurement and control instruments installed each year.

To help tap into this resource, the HART Communication Foundation (HCF—the technology owner and standards-setting body for the HART protocol) is offering a multi-part educational series of mini-courses on HART technology to help you better understand and more fully utilize the power of HART.

The first mini-course is available online at www.hartcomm.org . Additional installments will be added monthly. At the end of the series, a test will be given and a certificate awarded demonstrating proficiency in understanding HART.

Following are examples of the information that will be provided in the online mini-courses:

A backward-compatible enhancement for 4-20 mA instrumentation that enables remote, two-way digital communication with smart microprocessor-based field devices, HART communication devices support two simultaneous communication channels on the same wire—the 4-20 mA current loop analog communication channel and the HART digital communication channel.

All HART-enabled field devices contain 35-40 data items of information for improving plant operations and managing assets. These intelligent devices perform internal diagnostic checks and other functions, and then communicate information about their status on top of the 4-20 mA signal on the same wire.

HART Communication enables control systems to continuously monitor and validate integrity of a 4-20 mA current loop. Gateway interface solutions are also available for linking HART devices to systems based on network protocols, such as Ethernet, Modbus, and Profibus.

HART-smart field devices are real-time data servers with valuable process-related information. These devices continuously self-assess and self-monitor performance as well as supply device status and diagnostic information with every communication.

Other topics to be addressed in the online tutorials include:

How to use HART data from intelligent devices;

HART as part of asset management, control, and safety systems;

Sharing HART data in OPC servers and via ISA-88 and -95;

HART and the plant life cycle; and

Selection and implementation of HART devices.

Author Information

Ron Helson is executive director of the HART Communication Foundation;