Download What is Proximity?

What is Proximity?
Created by: ProvibTech
Proximity Outline
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Definition of Proximity?
What is a Proximity Sensor?
Why use a Proximity Sensor?
When to use a Proximity
Sensor/Transmitter?
How to use a Proximity Sensor?
Proximity Transmitters?
Definition of Proximity?
Nearness in place, time, order, occurrence,
or relation
 The region close around a person or thing
 Distance is a numerical description of how
far apart objects are
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What is a Proximity Sensor?
Detects presence of nearby objects
without any physical contact
 Detects movement or the presence of an
object and converts it to an electrical
signal
 often emits an electromagnetic or
electrostatic field and looks for changes in
the field or return signal
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Electromagnetism
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Magnetism arising from electric charge in
motion
Electrostatic
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The charge build up that usually occurs
because of electron imbalance at the
surface of materials
Types of Detection Systems
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Eddy Current or Inductive
◦ generated in metallic sensing objects by
electromagnetic induction
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Capacitive
◦ systems that detect changes in electrical
capacity when approaching the sensing object
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Magnetized
◦ systems that use magnets and reed switches
Why use a Proximity Sensor?
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Because ProvibTech made it!
Why use a Proximity Sensor?
High Reliability
 Machine vibration monitoring
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◦ Measure the variation in distance between a
shaft and its support bearing
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Long functional life
◦ Absence of mechanical parts
◦ Lack of physical contact between sensor and
the sensed object
When to use a Proximity Sensor/
Transmitter
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If needing to measure the following:
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Radial vibration
Axial thrust position/vibration
Shaft radial position
Vibration Amplitude and Phase Angle
Eccentricity
Phase Reference
When to use a Proximity Sensor/
Transmitter Cont’d
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Radial Vibration
◦ Vibration in a direction perpendicular to the
centerline of a shaft or rotor.
◦ Used for indicating bearing condition
◦ Measuring machine malfunction:
 Rotor imbalance
 Misalignment
 Shaft crack
◦ Potential bearing failure
When to use a Proximity
Sensor/Transmitter Cont’d
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Axial Thrust Position/Vibration
◦ Vibration in the direction of the centerline of a
shaft or rotor.
◦ Determining thrust bearing wear
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Shaft radial position
◦ Determining shaft position relative to rotor
amplitude angle
◦ Indicator of rotor stability and shaft alignment
◦ Vector monitoring
When to use a Proximity
Sensor/Transmitter Cont’d
When to use a Proximity Sensor/
Transmitter Cont’d
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Eccentricity
◦ Measures the shaft bow during startup of large
turbine machinery
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Phase Reference
◦ Measures shaft rotation speed and phase angle
of shaft vibration for monitoring and diagnostic
purposes
When to use a Proximity
Sensor/Transmitter
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Vibration amplitude and Phase Angle
◦ Diagnostic information in Polar and Bode
formats
How to use a Proximity Sensor?
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Things Needed:
◦ Probe
◦ Extension cable
◦ Driver
How to use a Proximity Sensor?
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This is how the complete system looks
once everything is connected together
How to use a Proximity Sensor?
When using a proximity sensor, distance is
always the most important thing
 Ideal GAP voltage = -10 VDC but -8 to
-12 VDC is also OK
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Proximity Transmitters
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TR3101
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TR3102
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TR4101
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TR4102
◦ Radial Vibration Transmitter
◦ 3 wire Transmitter
◦ Axial Vibration Transmitter
◦ 3 wire Transmitter
◦ Radial Vibration Transmitter
◦ 2 wire Loop-Powered Transmitter
◦ Axial Vibration Transmitter
◦ 2 wire Loop-Powered Transmitter