Administrador

Table of Contents

Introduction...............................................................................2 Need.for.Circuit.Protection........................................................4 . Types.of.Overcurrent.Protective.Devices. .................................8 Circuit.Breaker.Design............................................................. Types.of.Circuit.Breakers.........................................................23 Circuit.Breaker.Ratings............................................................27 . Time-Current.Curves. ..............................................................29 Selective.Coordination.............................................................32 Series-Connected.Systems.....................................................34Siemens.Circuit.Breakers........................................................37 Residential.Circuit.Breakers.....................................................38 . Panelboard.Circuit.Breakers. ...................................................46 . General.Purpose.Thermal-Magnetic.Circuit.Breakers. .............49Solid-State.Trip.Unit.Circuit.Breakers.......................................56 Internal.Accessories................................................................62 External.Accessories...............................................................65 VL.Circuit.Breakers.................................................................. 7 . WL.Circuit.Breakers. ...............................................................79Review.Answers......................................................................84 Final.Exam...............................................................................85 quickSTEP.Online.Courses......................................................88



Introduction

Welcome.to.another.course.in.the.STEP.series,.Siemens. Technical.Education.Program,.designed.to.prepare.our.distributors.to.sell.Siemens.Energy.&.Automation.products. more.effectively..This.course.covers.Basics of Circuit Breakers. and.related.products.. Upon.completion.of.Basics of Circuit Breakers.you.will.be.able. to: •. •. •. •. •. •. •. •. Explain.the.need.for.circuit.protection Identify.various.types.of.overcurrent.protective.devices Explain.the.basic.electro-mechanical.operation.of.a.circuit. breakerIdentify.various.types.of.Siemens.circuit.breakers Identify.circuit.protection.ratings.for.various.types.of. Siemens.circuit.breakers Describe.time-current.characteristics.on.a.time-current. curve Explain.the.benefits.and.function.of.circuit.breaker. coordination Identify.internal.and.external.circuit.breaker.accessories

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This.knowledge.will.help.you.better.understand.customer.applications..In.addition,.you.will.be.better.able.to.describe. products.to.customers.and.determine.important.differences. between.products..You.should.complete.Basics of Electricity before.attempting.Basics of Circuit Breakers..An. understanding.of.many.of.the.concepts.covered.in.Basics of Electricity.is.required.for.Basics of Circuit Breakers.. If.you.are.an.employee.of.a.Siemens.Energy.&.Automation.authorized.distributor,.fill.out.the.final.exam.tear-out.card.and. mail.in.the.card..We.will.mail.you.a.certificate.of.completion.if. you.score.a.passing.grade..Good.luck.with.your.efforts. Siemens.is.a.trademark.of.Siemens.AG..Product.names. mentioned.may.be.trademarks.or.registered.trademarks.of.their. respective.companies..Specifications.subject.to.change.without. notice. National ElectricalCode®.and.NEC®.are.registered.trademarks. of.the.National.Fire.Protection.Association,.Quincy,.MA.0269747.. Portions.of.the.National Electrical Code®.are.reprinted.with. permission.from.NFPA.70®,.National Electrical Code®. Copyright.©.2008,.National.Fire.Protection.Association,.Quincy,. MA.0269..This.reprinted.material.is.not.the.complete.and. official.position.of.the.National.Fire.Protection.Association....