NECA 420:2007
NECA 420:2007 Fuse Applications Describes application and installation practices and procedures for low-voltage, medium-voltage, and high-voltage fuses. Also applies to all classifications of fuses used for overcurrent protection of
Table of Contents
Foreword1.Scope
1.1ProductsandApplicationsIncluded
1.2RegulatoryandOtherRequirements
2.Definitions
3.ApplicationDataforFuses
3.1FuseTypesandClassifications
3.2FuseRatings
3.3Current-LimitingFuses
4.SizingandSelection
4.1SizingFusesforMain,Feeder,andBranchCircuits
4.2MotorProtection
4.3Drivers,Rectifiers,andInverters
4.4Series-RatedCircuitBreakers
4.5Elevator,Emergency,LegallyRequiredStandby,and
EssentialSystemsinHealthcareFacilities
4.6Capacitors
4.7TransformerProtection
4.8FirePumps
4.9WelderProtection
5.DesignConsiderations
5.1SystemStudies
5.2Conductors
5.3Finger-SafeFuseholders
5.4Fusibledisconnects
6.Receiving,inspecting,handling,andStorage
6.1Receiving
6.2Handling
6.3Storage
7.Installation
7.1EnvironmentalConditions
7.2GeneralInstallationRequirements
7.3FusePullers
7.4SpareFuses
7.5EnergizingEquipment
8.InspectionandMaintenance
8.1FrequencyofInspectionsandMaintenance
8.2RoutineInspectionsandTesting
8.3PeriodicCleaning,Inspection,andMaintenance
8.4Inspection,Testing,andFuseReplacementFollowing
anOvercurrentorGround-Fault
8.5FusesSprayed,Splashed,Soaked,orSubmersedUnder
Water
8.6InfraredScanning
8.7Troubleshooting
AnnexA:NECRequirementsforFuses
AnnexB:ReferenceStandards