Liquid Controls CIM100 - Manual (Page 5)

prIncIples of operatIon
principles of operation
1.. The.precision.turbine.flowmeter.is.a.volumetric.flow.measuring.device.
2.. Fluid.flowing.through.the.flowmeter.engages.the.vaned.rotor.and.causes.it.to.rotate.at.an.angular.velocity.proportional.to.the.
flow.rate.
3.. The.rotating.vanes.pass.by.the.pickup.coil.and.generate.an.electrical.signal.(AC.sine.wave.type)..The.sum.of.the.pulsing.
electrical.signal.relates.directly.to.the.flow.rate.
4.. The.electronics.of.the.integral.register.scales.and.divides.the.pulsing.electrical.signal.and.displays.the.measured.volume.in.the.
desired.unit.of.measure.
5.. The.differential.pressures.developed.across.the.turbine.flowmeter.balance.out.normal.downstream.thrust.loads,.which.
eliminates.the.need.for.thrust.bearings.over.the.rated.range.of.the.meter..
6.. The.vaned.rotor.is.the.only.moving.part.of.the.flowmeter.
pickup coil
varIable reluctance pIckups
Generating.pickups.contain.a.permanent.magnet.and.an.associated.wire-wound.coil..The.movement.of.the.ferrous.
material.of.the.rotor.blade.past.the.coil.tip.disrupts.a.magnetic.field,.producing.an.AC.signal.within.the.coil.winding.
pIckup coIl output
Pickup.coil.output.is.a.generated.AC.sine.wave.transmitted.via.2-wire.shielded.cable.that.minimizes.external.
interference..Variable.reluctance.coils.provide.the.highest.full.scale.frequency.and.a.lesser.signal/noise.ratio..
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