5
Instruction.Booklet.
IB48066
Effective November 2010
Instructions for Installation, Operation and Maintenance
of the Ampgard 720A Reduced Voltage Soft Starter
EATON CORPORATION www.eaton.com
A.second.low.voltage.compartment.door.is.located.on.the.front.of.
the.RVSS.medium.voltage.door ..The.keypad.operator.interface.is.
located.on.the.front.of.the.low.voltage.door.and.is.used.to.configure.
the.RVSS ..Refer.to.DEH41021.(Medium.Voltage.Solid.State.OEM.
Soft.Starter.Manual).for.details.on.operating.the.keypad ..(See.
Fig. 7.
)
Figure 7. Keypad Operator Interface
The.control.system.for.the.RVSS.is.located.in.this.low.voltage.com-
partment ..Components.include.the.CPU.board,.main.power.board,.
terminal.and.control.board,.and.CT.board ..(See.
Fig. 8.
)
Figure 8. Control System Boards
Section 2: Operation
WARNING
BARRIERS MUST BE INSTALLED BEFORE ENERGIZING STARTER.
FAILURE TO INSTALL BARRIERS CAN RESULT IN EQUIPMENT FAILURE,
SERIOUS INJURY, OR DEATH.
Starters.are.shipped.from.the.factory.with.barriers.installed.as.
shown.in.
Fig. 5
..
Refer.to.the.schematic.in.
Fig. 10
.for.the.following.description.of.
operation ..The.Ampgard.RVSS.includes.a.main.isolation.contactor.M.
that.closes.just.before.soft.start.ramping.begins.and.opens.after.a.
stop.is.completed ..During.a.fault.condition,.the.RVSS.control.system.
will.shut.down.the.soft.start.and.then.the.main.contactor.will.open ..
During.a.short.circuit.or.ground.fault.detected.by.a.separate.motor.
relay,.the.relay.will.immediately.open.the.main.contactor.to.limit.
potential.damage.to.the.system ..See.the.notes.on.the.schematic.for.
programming.the.relay ..
When.the.start.contact.is.closed.and.no.trip.condition.is.present,.
control.relay.CR.closes,.MXTD.closes,.and.main.contactor.M.closes ..
Main.contactor.aux.contacts.M2-M3.close.and.energize.control.
relay.RVX ..RVX.signals.the.RVSS.control.system.to.begin.ramping ..
Bypass.contactor.B.closes.when.the.motor.reaches.full.speed.as.
determined.by.both.time.and.current.settings .
To.allow.soft.stop.to.execute.fully,.timer.MXTD.has.been.placed.in.
the.control.circuit.to.delay.the.main.contactor.opening.until.soft.stop.
is.complete ..The.timer.delay.should.be.set.slightly.(5s).longer.than.
the.deceleration.time.selected.in.the.RVSS.configuration.set.point ..
If.soft.stop.is.not.required,.the.timer.should.be.set.at.1s.to.allow.
the.main.isolation.contactor.to.open.as.soon.as.the.soft.start.de-
energizes.the.motor ..
The.RVSS.is.set.at.the.factory.with.typical.starting.characteristics.
that.perform.well.in.most.applications ..After.the.power.and.con-
trol.connections.have.been.made,.use.the.initial.RVSS.settings.
to.operate.the.motor ..If.you.wish.to.review.the.settings.or.make.
adjustments.to.fit.your.application,.see.section.5 .1 .2.of.DEH41021.
(Medium.Voltage.Solid.State.OEM.Soft.Starter.Manual) .
