1. INTRODUCTION This document is written in order to provide guide lines for the modeling of power system apparatus for use in time - domain solution of electromagnetic transient phenomenon. This publication has been arranged in the following eight (8) parts. Part 1: Background Part 2: Power Electronics Part 3: Slow Transients Part 4: Switching Transients Part 5: Fast Front Transients Part 6: Very Fast Front Transients Part 7: Protection And Control Part 8: Bibliography A general statement of each area is as follows. 1.1 BACKGROUND This section presents a comprehensive summary of the background and state of the art for the transient solutions, representation of control systems, and modeling of power system components. 1.2 POWER ELECTRONICS The guideline presents the basic issues that are critical for successfully modeling of power electronics devices and the interface between power electronics and the utility or industrial system. Modeling aspects are presented for simulation of the semiconductor switching devices, power electronics system, snubber treatment, and simulation errors and control. A number of simulation examples, including FACTS modeling, are presented. 1.3 SLOW TRANSIENTS Modeling guidelines are presented for investigations of small signal torsional oscillations, large -signal shaft transient stresses, turbine -blade vibrations, fast bus transfer, controller interactions, harmonics interaction, and resonance phenomena. Sample test systems and simulation results are provided.