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Electrical UL/CSA > Selective Coordination
Selective Coordination

Example of a Fusible Coordinated System

More than ever, today’s electrical systems are one of the most important part of any office building, industrial plant, hospital or other facility.  A major blackout cannot be tolerated.  For this reason, selective coordination is critical, and required by the NEC®, for some installations.  The following address Code requirements for selective coordination and other related areas.

Selective Coordination Increases Reliability of Emergency SystemsSelective Coordination Increases Reliability

The 2005 and 2008 National Electrical Code® (NEC®) expanded the mandatory requirements for overcurrent protective device selective coordination to include power circuits supplying vital life-safety loads and national security/public safety power systems.

This article by Tim Crnko, Manager, Training & Technical Services with Cooper Bussmann provides insight into the need for selective coordination.

Why Selective Coordination is Mandatory

National Electrical Code requirements for selective coordination are mandatory for certain electrical systems where maximum reliability of power is critical.  The materials included in this section provide insight into the relationship between selective coordination, system reliability and life safety.  The reasoning for why selective coordination is mandatory.

Selective CoordinationUnderstanding Selective Coordination

This excerpt from the 2008 Cooper Bussmann SPD covers basic and advanced topics related to system coordination.  Information is presented as an aid to understanding selective coordination of overcurrent protective devices.

Selective Coordination ArticleSelective Coordination Articles

Articles on Selective Coordination including third party articles published in IAEI News and the necdigest provide important insight into the requirements and design of selectively coordinated systems, and the electrical systems where they are required.

Code RequirementsSelective Coordination Code Requirements

Here you will find articles relevant to NEC® requirements for selectively coordinated systems.  Different installations covered by different Code articles have varying requirements.  Some of the major Code requirements can be found in these documents.

Cooper Bussmann Quik-Spec Coordination PanelboardCooper Bussmann Quik-Spec Coordination Panelboard

The Cooper Bussmann® Quik-Spec™ Coordination Panelboard was designed specifically to meet the various Code requirements for selective coordination in a fully fused system.

Available with up to 200 Amps for a 600Vac or less system with up to 200kA SCCR, this panelboard features ampacity rejecting branch circuit disconnects up to 60amps.

Selective Coordination made easyCooper Bussmann Coordination Module

The Cooper Bussmann® Coordination Module™ was designed to help meet the various Code requirements for selective coordination.

Coordination RatiosFuse Coordination Ratios

This table contains amp ratios between line and load side fuses required to achieve selective coordination.

2008 Requirements2008 NEC® Coordination Updates

The 2008 edition of the NEC® contains all the requirements from 2005 with additional stipulations for Critical Operations Power Systems (COPS).  This document covers all the relevant Code sections and how to comply with all 2008 Selective Coordination requirements.

System ReliabilitySelective Coordination and System Reliability

This article addresses the role of the overcurrent protective device in system reliability.

Example StudySample Coordination Study

A coordination study requires considering many electrical system components. This sample study covers fuses, transformers, conductors and others.