Читать книгу Automation of Water Resource Recovery Facilities - Water Environment Federation - Страница 117

Loop testing confirms that each “control loop” in the system functions as designed. A control loop is a combination of one or more interconnected instruments that are arranged to measure or control a process variable (ISA-67.02.01-1999 and ANSI/ISA-5.1-1984).

All loop testing should be overseen and approved by the site engineer. Resulting loop sign-off sheets should be kept as test records. Consideration should be given to combining loop testing with I/O testing, especially if the integrator is also the instrument supplier. This could represent a significant reduction in costs for a project.