Heatcraft Refrigeration Products Air-Cooled Condensers none - Manual (Page 15)

15
E Series Motors with Integrated Variable Speed
E.Series.units.use.an.EC.motor/fan.blade.combination.to.provide.variable.speed.condenser.control ...All.components.required.
to.run.the.motor.at.variable.speeds.are.built.into.the.motor .
Speed Adjustment Characteristics
The.EC.motor.varies.it’s.speed.linearly.based.on.a.0-10V.input.signal ...At.10.VDC,.the.motor.runs.at.full.speed ...At.0.VDC,.the.
motor.turns.off ...A.chart.of.the.speed.control.curve.is.shown.below .
.
The.input.control.signal.can.be.supplied.from.any.controller.that.outputs.a.0-10.VDC.signal ...For.units.with.a.control.signal.
supplied.from.a.rack.control.or.other.external.controller,.the.unit.is.provided.with.a.terminal.board.for.control.signal.wiring ...
Units.with.factory.installed.proportional.pressure.controls.require.no.installation.wiring .
External Control Signal
Contact.control.manufacturer.for.setup.of.external.controller.to.provide.0-10.VDC.control.signal ...Wire.the.control.signal.to.
terminal.board.in.unit.control.box ...See.Diagram.#3.for.typical.external.signal.control.wiring .
Proportional Pressure Control
Units.with.factory.installed.proportional.pressure.controls.use.a.PI.controller.to.vary.the.motor.speed.in.order.to.maintain.a.
constant.desired.head.pressure ...The.PI.controller.has.five.user.adjustable.features:
•.Head.Pressure.Setpoint
•.Minimum.Output
•.Throttling.range
•.Integration.constant
•.Reverse.acting.or.direct.acting.mode.of.operation
Warning! When.connecting.the.unit.to.the.supply.power,..
. dangerous.voltages.occur ..Do.not.open.the.motor.within..
. the.first.5.minutes.after.disconnection.of.all.phases .
Be sure that the unit is isolated.
Warning! Dangerous.external.voltages.can.be.present..
. at.terminal.KL2.even.with.the.unit.turned.off .
Warning! With.a.control.voltage.fed.in.or.a.set.speed...
............... value.being.saved,.the.motor.will.restart.. . .
. automatically.after.a.power.failure .