The user manual for the Web Enabled Data Acquisition System (WEDAS), a system that supports the Power Reactor Information System (PRIS), provides instructions, guidelines and detailed definitions for each of the data items required for PRIS. The purpose of this manual is to ensure PRIS performance data are collected consistently and that the required quality of data collection is ensured. This PRIS-WEDAS user’s manual replaces reporting instructions published in the IAEA Technical Reports Series No. 428.