This paper presents the main features of a library of modules for representation of protective devices of distribution networks with distributed generation (DG). The impact of distributed generation in a distribution network depends, among other aspects, on the design of the protection system and the coordination between the different protective devices. The presence of distributed generation changes the radial nature of distribution systems and affects the performance of the protection system. This document discusses the present protection practices for distribution systems and DG interties, describes the implementation of protective devices (circuit breakers, relays, reclosers, fuses, sectionalizers) in an EMTP-type tool, and presents some simulation results whose main goal is to analyze the impact of synchronous machine-based embedded generators on the coordination between the different types of protective devices.