Ingeniero

Table of Contents

Introduction...............................................................................2 Need.for.Circuit.Protection........................................................4 Types.of.Overcurrent.Protection.Devices..................................6 Circuit.Breaker.Design...............................................................9Types.of.Circuit.Breakers.........................................................20 Circuit.Breaker.Ratings............................................................24 Time-Current.Curves. ..............................................................26 . Selective.Coordination.............................................................29 Series-Connected.Systems.....................................................3Siemens.Circuit.Breakers........................................................34 Residential.Circuit.Breakers.....................................................35 Panelboard.Circuit.Breakers. ...................................................43 . General.Purpose.Thermal-Magnetic.Circuit.Breakers. .............46 . Solid-State.Trip.Unit.Circuit.Breakers.......................................53Internal.Accessories................................................................59 External.Accessories...............................................................62 VL.Circuit.Breakers..................................................................68 WL.Circuit.Breakers. ............................................................... 76 .Review.Answers......................................................................86 Final.Exam...............................................................................88



Introduction

Welcome.to.another.course.in.the.STEP.series,.Siemens. Technical.Education.Program,.designed.to.prepare.our. distributors.to.sell.Siemens.Industry,.Inc..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.protection.devices Explain.the.basic.operation.of.a.thermal-magnetic.circuit. breaker Describe.time-current.characteristics.on.a.time-current. curve Define.important.circuit.breaker.rating.termsExplain.why.circuit.breaker.coordination.is.important Identify.internal.and.external.circuit.breaker.accessories Identify.the.various.types.of.Siemens.circuit.breakers Identify.circuit.protection.ratings.for.various.types.of. Siemens.circuit.breakers

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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.. After.you.have.completed.this.course,.if.you.wish.to.determine. how.well.you.have.retained.the.information.covered,.you.can.complete.a.final.exam.online.as.described.later.in.this.course..If. you.pass.the.exam,.you.will.be.given.the.opportunity.to.print.a. certificate.of.completion.from.your.computer. 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. NFPA70®, National Electrical Code®,.and.NEC®.are.registered.trademarks.of.the.National.Fire.Protection.Association®,. Quincy,.MA.0269.. NEMA®.is.a.registered.trademark.and.service.mark.of.the. National.Electrical.Manufacturers.Association,.Rosslyn,.VA. 22209. Underwriters.Laboratories.Inc.®.and.UL®.are.registered. trademarks.of.Underwriters.Laboratories.Inc.,.Northbrook,.IL. 60062-2096. Other.trademarks.are.the.property.of.their.respective.owners.

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Need for...