The Lamma Power Station in Hong Kong is using Opto 22 SNAP PAC standalone controllers to control heat, pressurization and other critical processes. The Opto 22 PACs connect to weigh scales, conveyors, pressure transducers, and thermocouples to ensure that the coal burning operations taking place at Lamma are executed safely and optimally.
For example, analog I/O modules wired to scales measure the weight of the coal prior to its delivery to the furnaces and sends these figures to the controller. Based on these readings—and whether they're low or high—the controller then instructs the conveyors delivering the coal to the furnaces to speed up or slow down appropriately, so the furnaces generate the proper amount of heat needed to spin turbines that produce the power.
At the same time, integrated circuit temperature derivative probes (ICTDs) connected to thermocouple analog input modules monitor the actual furnace temperatures, which are then used in PID calculations to regulate the temperature via analog output modules.