Johnson Controls Frick RXB Plus 12, Установка, эксплуатация и обслуживание

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RXB PLUS ROTARY SCREW COMPRESSOR UNITS
MAINTENANCE
070.101-IOM (JAN 13)
Page 62
be.direct.coupled.to.the.control.power,.analog.device,.and.
communications. grounding. and. may. cause. unexplained.
behavior.and.possible.damage.to.components..
To. install. correctly,. run. a. separate,. properly. sized. (10. or.
8. AWG. typically). insulated. ground. along. with. and. taken.
to.ground.with,.the.3-phase.ground.at.the.3-phase.supply.
transformer.(plant)..This.will.require.that.the.3-phase.ground.
and.the.control.power.ground.be.electrically.isolated.except.
for.the.connection.at.the.plant.supply.transformer..
This.style.of.grounding.should.steer.the.noise.(EMI/RFI).to.
earth.ground,.reducing.the.potential.for.it.to.affect.the.sensi-
tive.equipment,.which.could.occur.if.the.grounds.were.left.
coupled..
NOTE: If all other recommendations for ground-
ing are followed, this process should not be necessary.
CONDUIT
All. national. and. local. codes. must. be. followed. for. conduit.
with.regard.to.materials,.spacing.and.grounding..In.addition,.
Johnson Controls-Frick requirements must be followed
where they exceed or match national or local codes. Con-
versely, there is no allowance for any practices that are
substandard to what is required by national or local codes.
Johnson.Controls-Frick.conduit.requirements:
•. For.
variable frequency drives .(VFDs).of.any.type,.threaded.
metallic. or. threaded. PVC-coated. metallic. is. required.
for.both.the.power.feed.(line.side).from.the.source.and.
between.the.VFD.output.and.the.motor.(load.side).
•. PVC.conduit.is.acceptable. only .when. VFD rated cable .of.
the.proper.conductor.size.and.ground.is.used..This.applies.
to.both.the.line.side.and.load.side.of.the.drive..When.VFD.
rated. cable. is. not. used,. threaded. metallic. or. threaded.
PVC-coated.metallic.must.be.used..
•. When.threaded.metallic.or.threaded.PVC-coated.metallic.
is.used,.it.must.be.grounded.at.both.ends..
•. When. not. required. to. be. in. metal. or. other. material. by.
national. or. local. codes,. conduits. for. the. power. feed.
(3-phase).of.constant.speed.starters.may.be.PVC..
•. When. not. required. to. be. in. metal. or. other. material. by.
national.or.local.codes,.conduits.between.a.constant.speed.
starter.and.the.motor.(3-phase).may.be.PVC..
•. Any. unshielded. control. voltage,. signal,. analog,. or.
communication.wiring.that.does.not.maintain.12.inches.
of.separation.from.any.3-phase.conductors.for.every.33.
feet.(10.meters).of.parallel.run.must.be.in.metal.conduit.
which.will.be.grounded..
Separation:.(0-33.feet,.0-10.meters.–.12.inches,..3.meters),.
(33-66.feet,.10-20.meters.–.24.inches,..6.meters).
•. Since. PVC. conduit. does. absolutely. nothing. to. protect.
lower.voltage.lines.from.the.magnetic.field.effects.of.higher.
voltage.conductors,.running.either.the.lower.or.the.higher.
voltage.lines.in.PVC,.does.not.reduce.these.requirements.
on.separation..Only.running.in.metal.conduit.can.relieve.
these.requirements..
•. Due.to.the.level.of.EMI.that.can.be.induced.onto.lower.
voltage.lines.when.running.multiple.feeders.in.a.trench,.
control.power,.communications,.analog,.or.signal.wiring.
cannot.be.run.in.trenches.that.house.multiple.conduits/
electrical.ducts.carrying.3-phase.power.to.starters/vfd.or.
motors..
•. Control.power,.communications,.analog,.or.signal.wiring.
should.be.run.overhead.(preferred).or.in.a.separate.trench..
If.these.lines.are.not.in.threaded.metallic.or.threaded.PVC-
coated.metallic,.abiding.by.the.separation.requirements.
noted.above.is.necessary.
•. Though.not.recommended,.if.cable.trays.are.used,. metallic .
dividers.must.be.used.for.separation.of.conductors.of.unlike.
voltages.and.types.(AC.or.DC).
NOTE: When in doubt contact the factory or use threaded
metallic or threaded PVC coated metallic conduit.
WIRING PRACTICES
Do.not.mix.wires.of.different.voltages.in.the.same.conduit..
An. example. of. this. would. be. the. installation. of. a. screw.
compressor.package.where.the.motor.voltage.is.480.volts.
and.the.electronic.control.panel.power.is.120.volts..The.480.
volt.circuit.must.be.run.from.the.motor.starter.to.the.motor.
in.its.own.conduit..The.120.volt.circuit.must.be.run.from.the.
motor. starter. control. transformer. to. the. electronic. control.
panel.in.its.own.separate.conduit..If.the.two.circuits.are.run.
in.the.same.conduit,.transients.on.the.480.volt.circuit.will.be.
induced.onto.the.120.volt.circuit.causing.functional.problems.
with.the.electronic.control.panel..Metallic.dividers.must.be.
used.in.wire.way.systems.(conduit.trays).to.separate.unlike.
voltages..The.same.rule.applies.for.120.volt.wires.and.220.
volt.wires..Also,.never.run.low.voltage.wires.for.DC.analog.
devices.or.serial.communications.in.the.same.conduit.with.
any.AC.wiring.including.120.volt.wires..See.Figure.24.
Figure 24
Never run any wires through an electronic control panel
that do not relate to the function of the panel.
.Electronic.
control.panels.should.never.be.used.as.a.junction.box...These.
wires.may.be.carrying.large.transients.that.will.interfere.with.
the.operation.of.the.control.panel.
An extreme example of
this would be to run 480 volts from the starter through
the electronic control panel to an oil pump motor.
When.running.conduit.to.the.electronic.control.panel,.use.
the.access.holes.(knockouts).provided.by.the.manufacturer..
These.holes.are.strategically.placed.so.that.the.field.wiring.
does.not.interfere.with.the.electronics.in.the.panel..Never.al-
low.field.wiring.to.come.in.close.proximity.with.the.controller.
boards.since.this.will.almost.always.cause.problems.