Process monitors measure and analyze temperature, pressure, flow and other processing parameters to maintain product quality and safe production operating conditions. They usually consist of sensors, cables, input terminals, and integrated software. Typically, multiple algorithms are applied to each signal that comes from a sensor. These input signals are monitored for an integrated value or a peak input value, and can track different variables.
With process monitoring systems, tolerances can be set to detect problems such as short or double feeds, faulty transfers, collisions, and damage to tools. Systems that count every part and stop a machine at a preset total help to improve operator efficiency and reduce costly overruns. Process monitors with programmable tolerances, crash limits, mode indication status, process deviation indicators, and downtime analysis are commonly available. Features may also include revolutions per minute (RPM) tracking, historical error logging, shop floor data entry, and a supervisor lock-out option.
Applications and Industries
Process monitors are used in many different applications and industries. For example, semiconductor and liquid crystal process monitors are used to improve the yield of etching and film fabrication processes. These devices monitor parameters such as film thickness, trench depth, and plasma levels. Thin film process monitors are used to control thin film deposition rates or composition during thin film processing. Products use quartz crystal microbalances, ellipsometers, and spectrometers. Chemical process monitors are used to manage the flow from feed pumps and control valves, and to check chemical concentrations in tanks. These process monitoring systems can be installed either in the process stream or at the point-of-use where chemicals are delivered and then blended. Industry-specific process monitors are also used with cold forming, metal cutting, thread rolling, metal stamping, forging, tapping, and drilling operations. Process monitors and process monitoring systems are often used in conjunction with larger, plant-based control systems. Products such as plant performance monitors can be used to monitor multiple process units on a single screen. Complete plant and process monitoring systems (PPMS) are scalable process monitors that provide continuous, real-time information and trend analysis. Advanced process monitoring software that uses proprietary software and operating systems (OS) such as Microsoft Windows is also available. Microsoft and Windows are registered trademarks of Microsoft Corporation.