Page 2 - Introduction; Basics of Panelboards; National Electrical
2 Introduction Welcome.to.another.course.in.the.STEP.series,. S iemens. T echnical. E ducation. P rogram,.designed.to.help.our.distributors. and.customers.better.understand.Siemens.Industry,.Inc..products..This.course.covers. Basics of Panelboards . Upon.completion.of. Basics of Panelboards, .you.wi...
Page 4 - Distribution Systems; Power distribution systems
4 Distribution Systems Power distribution systems .are.used.in.every.residential,. commercial,.and.industrial.building.to.safely.control.the.distribution.of.electrical.power.throughout.the.facility.. Residential Power . Most.of.us.are.familiar.with.the.power.distribution.system Distribution found.in...
Page 6 - Panelboards; panelboards
6 Panelboards Electrical.distribution.systems,.whether.simple.or.complex,.typically.include. panelboards ,.the.focus.of.this.course.. Even.the.load.center.used.in.a.home.is.a.type.of.panelboard..However,.the.focus.of.this.course.is.on.panelboards.used.in.commercial.and.industrial.facilities. Panelbo...
Page 7 - National Electrical Code; Lighting and appliance branch-circuit panelboards
7 1.75 in. (44 mm) 0.25 in. (6 mm) Used to Control Light, Heat, or Power Circuits Mounted in or Against a Wall Placed in a Cabinet or Cutout Box Accessible Only From the Front Flush Mounted Surface Mounted For.additional.information,.refer.to. National Electrical Code ®. Article.408,.Switchboards.an...
Page 8 - Review 1; NEC
8 Prior.to.the.2008. National Electrical Code® ,.the.distinction. between.these.two.panelboard.types.was.described.in. NEC® . Articles.408.34.and.408.35..These.articles.placed.restrictions.on.lighting.and.appliance.panelboards.and.indicated.that.panelboards.that.did.not.comply.with.these.restriction...
Page 9 - Overcurrent Protection Devices; ampacity; short circuit
9 Overcurrent Protection Devices Because.current.flow.in.a.conductor.always.generates.heat,.the.greater.the.current.flow,.the.hotter.the.conductor..Excess.heat.is.damaging.to.electrical.conductors..For.that.reason,.conductors.have.a.rated.continuous.current.carrying.capacity.or. ampacity ..Current.b...
Page 14 - Circuit Breaker
4 When.an.overcurrent.occurs,.the.circuit.breaker.trips.to.remove.power.from.the.circuit..The.greater.the.overcurrent,.the.more.rapidly.the.circuit.breaker.trips..Once.the.overcurrent.condition.has.been.corrected,.a.simple.flip.of.the.breaker’s.operating.handle.restores.the.circuit. The.ability.to.r...
Page 15 - NEB Circuit Breaker
5 Some.circuit.breakers.have.what.is.referred.to.as.a.“slash”.voltage.rating,.such.as.20/240.VAC.or,.as.shown.in.the.following.graphic,.600/347.VAC.for.2,.3,.or.4-pole.NEB.breakers.and.5/250.VDC.for.2-pole.NEB.breakers..In.such.cases,.the.breaker.may.be.applied.in.a.circuit.where.the.nominal.voltage...
Page 19 - Panelboard Construction
9 Panelboard Construction Panelboards.are.available.in.different.sizes.with.variations.in.construction..The.components.that.make.up.a.panelboard,.however,.are.similar..Panelboards.contain.a.can,.interior,.circuit.protection.devices,.label,.and.trim.. Can . The. can .is.typically.constructed.of.galva...
Page 20 - NEC®
20 Interior . The. interior .consists.of.several.components,.including. overcurrent.protection.devices,.bus.bars.and.insulated.neutral.bus.bars..A.lighting.panel.interior.is.mounted.to.the.four.mounting.studs.in.the.can..Jacking.screws.(not.shown).allow.adjustment.of.the.interior.within.the.enclosur...
Page 21 - B phase
2 High Leg . Some.power.supply.systems.use.a.transformer.with.a.three-phase,.four-wire.(3Ø4W),.delta-connected.secondary.with.grounded,.center-tap.connection.on.one.phase..The.following.illustration.shows.an.example.of.such.a.system.with.240.volts.phase-to-phase..The.midpoint.of.one.phase.winding.is...
Page 23 - Circuit Identification; Panelboard Label
23 Circuit Identification . Specifications.typically.require.panelboard.circuit.terminals.to.be.labeled.or.for.a.wiring.diagram.to.be.provided..One.approach.for.numbering.terminals.is.to.use.odd.numbers.for.poles.on.the.panelboard’s.right.(your.left.as.you.face.the.panelboard).and.even.numbers.on.th...
Page 24 - Filler Plates
24 Dead Front and Trim . The. dead front .and. trim .are.the.front.surfaces.of.the. panelboard.that.cover.the.interior..The.trim.includes.an.access.door..These.components.provide.access.to.the.overcurrent.devices.while.sealing.off.the.bus.bars.and.internal.wiring.from.contact. Access Door Trim Dead ...
Page 26 - Installation; working
26 Installation . Panelboard.installation.requires.careful.planning.to.ensure.a.safe.environment.for.personnel.and.equipment..Article.0.26.of.the. NEC® .covers.spaces.about.electrical.equipment,.such.as. panelboards.. The.intent.of.Article.0.26.is.to.provide.enough. working space .for.personnel.to.e...
Page 27 - Individual Overcurrent Protection; Split Bus
27 Individual Overcurrent Protection NEC® Article.408.36.requires.panelboards.to.be.protected.by. an.overcurrent.protection.device.with.a.rating.that.does.not.exceed.the.panelboard’s.rating.. The.following.illustration.shows.two.ways.individual.panelboard.overcurrent.protection.can.be.accomplished.....
Page 28 - split bus; Panelboard Supplied
28 When.two.main.circuit.breakers.are.used.in.a.panelboard,.a. split bus .is.used..Half.of.the.branch.circuits.are.protected.by. one.main.circuit.breaker,.and.the.other.half.are.protected.by.the.other.main.circuit.breaker..Keep.in.mind.that.the.combined.ratings.for.these.circuit.breakers.must.be.no....
Page 29 - Panelboards Main Configurations; Main Breaker Panelboard
29 Panelboards Main Configurations There.are.three.types.of.panelboard.main.configurations:.main.lug.only,.main.breaker,.and.main.switch..In.this.context,.the.term.switch.refers.to.a.fusible.switch..All.three.of.these.configurations.are.available.for.power.panels..Lighting.panels.are.available.with....
Page 34 - Review 3
34 Sub-feed Breaker . When.an.application.requires.a.circuit.breaker.that.is.a.larger.frame.size.than.the.branch.circuit.breakers.available.and.will.not.fit.in.a.branch.circuit.location,.a. sub-feed breaker .can.be. used..One.possible.application.is.to.supply.a.second.panelboard.located.some.distanc...
Page 35 - Power Supply Systems; Ø3W Power System
35 Power Supply Systems Panelboards.receive.power.from.a.variety.of.sources..For.example,.a.downstream.panelboard.typically.receives.power.from.an.upstream.panelboard.or.switchboard..However,.power.for.the.distribution.system.originates.from.a.utility.power.company..Power.from.the.power.company.is.s...
Page 38 - Service Entrance Panelboards
38 Service Entrance Panelboards Sometimes.panelboards.are.used.as. service entrance equipment .for.a.building..This.is.the.equipment.located.near. where.the.power.enters.the.building..The.incoming.power.is.connected.to.this.equipment.which.provides.a.means.to.control.and.cut.off.the.supply.. Accordi...
Page 39 - Disconnects Versus Poles
39 In.the.example.on.the.right,.a.main.lug.only.panelboard.is.equipped.with.up.to.six.circuit.breakers.to.disconnect.power.to.all.equipment.being.supplied.by.the.service.. Regardless.of.which.of.these.examples.is.used,.each.circuit.breaker.must.be.clearly.labeled.to.show.the.load.it.supplies.. Main ...
Page 40 - Panelboard Grounding; Grounding; Service Entrance Grounding
40 Panelboard Grounding Grounding .is.an.important.aspect.of.any.electrical.equipment. and.must.be.considered.carefully..A.ground.connection.is.a.connection.to.earth.or.to.a.conductive.object.that.is.connected.to.earth..The.accompanying.illustration,.for.example,.shows.the.neutral.(N).conductor.of.a...
Page 41 - Bonding; Equipment Grounding Bus
4 The.neutral.and.the.panelboard.enclosure.are.bonded.together.at.the.service.entrance.so.that.the.enclosure.is.also.connected.to.ground.through.the.grounding.electrode.connector.. Bonding . permanently.joins.metal.parts.to.form.a.low-resistance.path.for.electrical.current. Power Source Neutral Bus ...
Page 42 - Fault Path
42 Grounding Panelboards . The.neutral.conductor.is.only.connected.to.ground.at.the Downstream . service.entrance..As.shown.in.the.following.illustration,.when.a.downstream.panel.is.used,.the.neutral.is.isolated.from.ground.in.that.panel.and.connected.to.the.neutral.bus.in.the.service.entrance.panel...
Page 43 - Review 4
43 Review 4 .. If.the.secondary.of.a.four-wire,.wye-connected. transformer.is.480.V.phase-to-phase,.the.phase.to.neutral.voltage.is._____.V. 2.. If.the.secondary.of.a.four-wire,.delta-connected,.BØ. high.leg.transformer.is.240.volts.phase-to-phase,.determine.the.following..phase.to.neutral.voltages....
Page 44 - Ground Fault Protection; ground fault
44 Ground Fault Protection A. ground fault .is.a.condition.in.which.electrical.current. unintentionally.flows.to.ground..Because.ground.faults.can.cause.damage.to.equipment.and.can.endanger.lives,.ground.fault.protection.is.required.in.some.situations.. For.example,. NEC® .Article.230.95.requires. g...
Page 46 - Panelboard Interrupting Ratings
46 Panelboard Interrupting Ratings Interrupting Rating . When.selecting.panelboards.and.overcurrent.protection.devices,.it.is.essential.to.know.the.available.fault.current.for.an.application.and.the.interrupting.rating.for.the.protective.devices.under.consideration.for.use.in.the.panelboard. NEC® .A...
Page 47 - Series Rating Method; Series Connected
47 Series Rating Method . An.alterative.to.the.full.rating.method.is.the.series.rating.method,.which.requires.that.the.main.upstream.circuit.protection.device.must.have.an.interrupting.rating.equal.to.or.greater.than.the.available.fault.current.of.the.system,.but.subsequent.downstream.circuit.protec...
Page 48 - Siemens P Series Panelboards; Siemens P series of panelboards
48 Siemens P Series Panelboards Siemens P series of panelboards .offers.a.stepped.approach. to.power.distribution..The. P1 .panel.fits.the.majority.of.lighting. panel.needs.in.a.cost.effective.package..P.offers.a.flexible.design.that.virtually.eliminates.the.impact.of.common.mistakes.in.feed.directi...
Page 49 - General Specifications; Enclosure Options
49 General Specifications . P.series.panelboard.interiors.are.designed.to.accommodate.top.or.bottom.feed..Regardless.of.which.is.specified.for.three-phase.panels,.branch.device.poles.are.arranged.with.the.uppermost.pole.always.on.“A”.phase,.the.second.pole.down.always.on.“B”.phase,.and.the.third.pol...
Page 52 - P2 Panelboards
52 P2 Panelboards . P2.panelboards.offer.a.wide.variety.of.factory-assembled.options.to.meet.most.lighting.panel.application.requirements..The.P2.design.also.offers.the.ability.to.mix.breaker.frames.in.unit.space.up.to.250.A.to.meet.many.power.distribution.panel.requirements.in.a.much.smaller.packag...
Page 53 - P3 Panelboards
53 P3 Panelboards . P3.panelboards.are.small.footprint.power.distribution.panelboards.designed.for.use.in.applications.that.require.more.or.larger.branch.devices.than.a.lighting.panelboard.typically.includes.. P3.panelboards.can.include.a.wide.variety.of.factory.assembled.options.and.have.the.abilit...
Page 54 - P4 and P5 Panelboards; P4 and P5 power panelboards
54 P4 and P5 Panelboards P4 and P5 power panelboards .are.similar.in.design.and. features,.but.vary.in.the.ratings.available..P4.panelboards.have.a.medium.footprint.to.fit.applications.that.require.more.or.larger.branch.devices.and.higher.current.ratings.than.lighting.and.appliance.panelboards.can.a...
Page 55 - P Series Panelboard Catalog Numbers
55 P Series Panelboard Catalog Numbers The.following.P.series.panelboard.catalog.number.description.provides.summary.information..For.more.detail.including.information.on.circuit.breaker.selection,.refer.to.the.SPEEDFAX.catalog.. The.catalog.number.provides.a.description.of.the.panelboard..There.are...
Page 57 - Review 6
57 You.can.minimize.the.potential.for.error.when.ordering.panelboards.by.making.sure.that.you.have.the.correct.answers.to.the.following.questions. •. What.is.the.power.system.(voltage,.phases,.number.of.wires)? •. What.is.the.interrupting.rating.required.for.the.panel? •. Which.NEMA.type.enclosure.i...
Page 58 - Quick-Spec Coordination Panelboards; Quick-Spec coordination panelboards
58 Quick-Spec Coordination Panelboards Siemens. Quick-Spec coordination panelboards .provide. fusible.solutions.that.make.it.simple.and.cost.effective.to.selectively.coordinate.a.fused.electrical.distribution.system..These.panelboards.are.designed.to.address.the. NEC® .selective. coordination.requir...
Page 59 - Additional Types of Panels and Cabinets; C1 and C2 panelboards
59 Additional Types of Panels and Cabinets In.addition.to.the.P.series.and.coordination.panelboards.described.in.this.course,.Siemens.also.offers.C.and.C2.column.type.panelboards,.lighting.control.panels,.and.telephone.and.equipment.cabinets. Siemens. C1 and C2 panelboards .have.a.narrow.width.suita...
Page 60 - Accessories; Shunt Trip
60 Accessories Accessories.add.to.the.performance.of.a.panelboard.or.adapt.the.panelboard.for.specific.application.requirements..Various.accessories.are.available.for.Siemens.panelboards..The.shunt.trip.accessory.described.on.this.page.is.just.one.example.of.a.circuit.breaker.accessory..Refer.to.the...
Page 62 - Siemens; TPS3 SPDs
62 TPS3 Transient Protection .. Many.electrical.devices.and.systems.are.susceptible.to Systems . damage.from.the.high.energy.levels.associated.with.electrical.surges.caused.by.lightning.or.other.electrical.equipment...Any.component.between.the.source.of.the.surge.and.ground.can.be.damaged..Therefore...
Page 63 - Power Meters
63 Power Meters . In.today’s.complex.business.climate,.power.monitoring.systems.often.require.meters.with.a.range.of.capabilities.from.basic.energy.and.power.meters.to.advanced.power.quality.meters.that.can.accumulate.data.from.a.variety.of.sources..In.addition,.while.small.systems.often.need.low-co...
Page 65 - Review 7
65 Review 7 .. Siemens.________.panelboards.provide.fusible. solutions.that.make.it.simple.and.cost.effective.to.selectively.coordinate.a.fused.electrical.distribution.system.. 2.. Siemens.________.and.________.panelboards.have.a. narrow.width.suitable.for.column.mounting. 3.. A.________.is.a.circui...
Page 66 - Review Answers
66 Review Answers Review 1 . ).power.distribution;.2).b;.3).2008. Review 2 . ).can;.2).interior;.3).bus.bar;.4).split;.5).dead.front,.trim. Review 3 . ).man.breaker,.main.lug.only,.main.switch;. . 2).horizontally,.vertically;.3).lug.only;.4).Feed-thru;.5).Sub-feed;.6).sub-feed. Review 4 . ).277;.2)....
Page 68 - Final Exam
68 Final Exam Before.taking.the.final.exam,.it.is.recommended.that.you.delete.the.temporary.internet.files.from.your.computer’s.web.browser..For.most.versions.of. Internet Explorer ,.you.can.do.this.by. selecting. Internet Options .from.the. Tools .menu.and.then. clicking.on.the. Delete Files .butto...
