When a process deviates from its normal state, process operators should start to check instruments and analyze the process to find out the causes of the deviation. Field operators usually go to examine the relevant equipment, sharing information on the process over the radio with workers in the control room. But the radio system could cause time delay and have some limitation in communicating detailed information. To overcome these drawbacks, the wireless process monitoring system has been developed and applied to the LNG terminal in this work. This system is expected to help users who move frequently around the plant do their job in many ways. For example: Field operators can access values monitored in the control room while reading field values from sensors, Unit process operators can check the process state on the spot when the process is resumed after repair work and Managers can monitor the process anywhere in the plant.
A converged PDA operating in Windows CE is adopted as a mobile device for its compactness and portability.