Purged and Pressurized Systems

摘要

This is a continuation of my last column, which was about the different types of purged and pressurized systems used in modern control rooms. Electrical control components and instrumentation devices and other equipment located in control rooms at refineries, chemical plants and similar facilities also are suitable for use in hazardous or classified locations. If purged and pressurized systems are installed in these rooms, the National Electrical Code (NEC) permits general-purpose equipment intended for use in unclassified locations.