What is WirelessHART?
WirelessHART is a wireless communication network designed especially for sensors used in process automation. It connects individual sensors to a distributed control system (DCS) or asset management system.
What makes a WirelessHART system work?
A typical WirelessHART system consists of a flat mesh network, time division multiple access (TDMA), frequency hopping spread spectrum (FHSS), and a network manager in the gateway.
- Flat mesh network — A mesh network is one where there are multiple nodes consisting of wireless field devices. If one node fails, another one can take over to keep the network up and running. This ability is referred to as “self-healing.” Why is it called “flat?” It is called “flat” because every node can function as either a signal source or a repeater, without one particular node being in charge.
- TDMA — Allots a set amount of communication time for each WirelessHART field device so that each one gets a turn to communicate.
- FHSS — Keeps frequencies separate and secure.
- Network manager — Controls the network, usually from the gateway.
What is the principle behind WirelessHART? How does it work?
WirelessHART takes a well-known and accepted communication protocol, Highway Addressable Remote Transducer (HART), and combines it with wireless technology that is commonplace in the home and at work. It utilizes the 2.4 GHz industrial, scientific, and medical (ISM) frequency band, and the customer can use the same configuration, maintenance, and diagnostic procedures that HART uses.
How do I mount or install WirelessHART?
The most common way to set up WirelessHART is by using a mesh network topology, which offers redundancy in case one of the nodes goes down. A mesh network can extend for hundreds of meters. Make sure that the WirelessHART field devices are at least 0.5 m from walls to avoid noise reflection, at least 0.5 m apart from each other to avoid cross-talk, and 1.5 m off the ground for best results.
What can you do with WirelessHART? What kinds of applications or industries is it used in?
WirelessHART is ideal for use in tank farms. Typical applications include oil and gas, water and waste water treatment, power, chemical, and pharmaceutical.
Why is WirelessHART better than other options?
The advantage that WirelessHART has over other options is its ability to maintain a reliable and secure network. This is accomplished by the four items referred to earlier in this blog: flat mesh network, time division multiple access, frequency hopping spread spectrum, and a network manager in the gateway.