This Practice provides the requirements¿including design, installation, inspection, testing, shipment, and documentation¿for the purchase of a complete on-line, pulse-width-modulated (PWM) uninterruptible power supply (UPS) system for application in process industries. This Practice and PIP ELSAP04D - Data Sheet for Pulse-Width-Modulated (PWM) Uninterruptible Power Supply (UPS) System - define the minimum requirements for a complete on-line, PWM-type UPS system. These include requirements for design, fabrication, inspection, testing, shipment, and documentation. PWM-type UPS systems include a rectifier/charger, inverter, static bypass switch, manual bypass switches, transformers, and accessories. Batteries are not covered by this Practice.