EJX110B Wireless Differential Pressure Transmitter

Geothermal power plants create electricity from geothermal energy. These power plants are similar to other steam turbine station; however their heat source is that of the earth's core. The created steam is used to turn the turbine for the production of electricity. Technologies include Dry steam, Flash steam and Binary cycle power stations with Binary cycle being the most common geothermal plant in current production. In the process of geothermal power generation the facility needs to monitor various processes, as in this case steam line pressure sits in remote from control room's location.

The client wanted to monitor the injection gas pressure of gas lift remotely in central control room. Antitheft measures are needed to install new equipments and cables.

Both bulk and finished inventories are stored in distributed tank farm remote from the site operations. These are difficult to instrument due to the infrastructure cost involved. These are then monitored daily by patrol rounds. While effective, this method does require a large skilled labor force to monitor all of tanks. This can impose an additional risk when the stored medium is of a hazardous nature.

ISA100 wireless temperature and pressure transmitters.

ISA100 wireless temperature and pressure transmitters with orifice plates allow:

• No cabling installations or maintenance.
• Small amount of hardware and simple equipment implementation means minimizing potential vandalism.

ISA100 Wireless Monitoring  

• Gateway x1, Temperature Transmitter (YTA) x3, Pressure Transmitter (EJX) x1, Repeater x1

Gateway is installed at control room and 3m height extended antenna is set.

• Oil level measurement of diesel tanks that feed fuel to their diesel generator's which are at three locations and 400 meters apart from each other.
• Also to measure level , pressure and flow to and from their main storage yard.

ISA100 Wireless Temperature and Pressure Transmitters

• Gateway x1, Temperature Transmitter (YTA) x1, Pressure Transmitter (EJX) x1

High quality wireless communication confirmed

• Packet Error Rate (PER) is 0 to 2.5%/ 5 days

The use of wireless technology in industrial automation systems offers a number of potential benefits, from the obvious cost reduction brought about by the elimination of wiring to the availability of better plant information, improved productivity and better asset management. However, its practical implementation faces a number of challenges: not least the present lack of a universally agreed standard. This article looks at some of these challenges and presents the approach being taken by Yokogawa.

In recent years, more field wireless devices have been used in hazardous areas. Meanwhile, in plants that are usually recognized as hazardous areas, there are numerous metallic tanks and pipes that easily shield or reflect radio waves, as discussed later, thus resulting in a poor environment for wireless communication.

The innovation of wireless technology increases the use of wireless communication in the industry. The introduction of wireless communication to plants, however, requires strict features such as robustness, real-time responsiveness, and low power consumption. This has restricted the use of wireless communication to limited applications such as data logging and device status monitoring that does not require strict real-time responsiveness and data arrival reliability in communication.