Читать книгу Automation of Water Resource Recovery Facilities - Water Environment Federation - Страница 71

Uninterruptible power supply requirements should be clearly defined in the specifications. The design engineer should prepare initial sizing calculations for all control equipment to provide this information to the electrical design engineer for correct sizing of breakers and cabling. Final UPS sizing should be left up to the system integrator based on specified design criteria, such as a percentage of connected load 125 to 150% for a defined time (e.g., for half an hour, 1 hour, or other desired period of time). For facilities with on-site generators, a half-hour UPS battery on time is typically sufficient to allow on-site power generators to be fully online in case of utility power failure.