Chapter02 fa14

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Chapter 02 Supplement and reinforcement of Input Devices and Output Actuators

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Chapter 02 I/O Devices and Sensors

Transcript of Chapter02 fa14

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Chapter 02

Supplement and reinforcement ofInput Devices and Output Actuators

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I/O Devices

I/O can be categorized into three areas or types: Binary (Discrete) (Unfortunately to add some confusion they are

also referred to as Digital) This includes all mechanical switches such as: pushbuttons,

selectors, limit (micro), motor starter aux. contacts, relay contacts, etc.

It also includes all solid state sensors such as: photoelectric, inductive and capacitive proximity, etc.

Digital This includes: processed video, charge coupled devices

(CCD) arrays, inductive coil impulse generators, optical code wheels (encoders), etc.

Analog This includes: potentiometers, linear variable differential

transformers (LVDT), video correlation, pressure, temperature, flow, strain, etc.

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I/O Details

Mechanically operated switches are mode up of: Pole (sometimes referred to as a wiper) Contact Actuator

Pole orWiper

Pole orWiper

Contact

Contact

Contact

SPST Switch

SPDT Relay

SPSTDB SwitchSingle Pole Single Throw Double Break

Pole orWiper

Contacts

SPDTDB SwitchSingle Pole Double Throw Double Break

Pole orWiper

Contacts

Contacts

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Mechanical Switches

Normally Open Normally Closed

Normally Open

Normally Closed

Push Buttons

Selectors

Limit (micro)

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Mechanical Switches

Normally Open

Normally Closed

Normally Open

Normally Closed

Normally Open

Normally Closed

Normally Open

Normally Closed

Normally Open

Normally Closed

FLOAT SWITCH PRESSURE SWITCH TEMPERATURE SWITCH

FLOW SWITCH FOOT SWITCH

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Relays

Electro-MechanicalNC

NONC

NO

POLE

POLE

NO NC

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Switch Bounce

Switch contact bounce

Ø V

+V

+V

PLCInput

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Switch contact bounce

Switch Bounce

Ø V

+V

+V

PLCInput

SwitchCloses

Switch comes to

rest

Random‘Bounce’

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Sensors

Photoelectric, Inductive and Capacitive

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Sensing Theory Primer

Sensors provide the equivalence of eyes, ears, nose and tongue to the microprocessor of a PLC/PAC or computer.

Microprocessor

Opticalsensor

Gassensor

Microphone

Probe

Graphic from: Petruzella, Frank D. (2005). Programmable Logic Controllers (3rd ed.). New York, NY: McGraw-Hill

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Review of Basic Solid State Devices

Brief review of: Diodes

Multiple uses within PLC/PAC control circuits DC flyback protection (Inductive surge suppression

for DC inductive loads) Transistors

Commonly used in PLC/PAC DCV output modules Silicon Controlled Rectifiers (SCR) Triac

Commonly used in PLC/PAC ACV output modules

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Diode

Current flow in one direction only.

CathodeAnode

Direction ofConventional Current

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Forward Bias

A diode will conduct current when the anode is 0.7V more positive than the cathode. When current is flowing the diode is Forward Biased.

+

Direction ofCurrent Flow

+

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Reverse Bias

A diode will not conduct current when the anode is not 0.7V more positive than the cathode. When current is not flowing the diode is Reverse Biased.

NO CURRENT FLOW

++

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Transistor

Transistors are commonly used as the switching device in PLC/PAC DCV output modules. Just like a diode, a 0.7V bias is required for current flow.

Transistors are available in two polarities, NPN & PNP. NPN Sink PNP Source

NPN PNP

+

+

+

+

+

+

Emitter Emitter

Base Base

Collector Collector

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Field Effect Transistors

Field Effect Transistors (FETs) can also be used as switches.

Transistors are current operated devices and FETs are voltage operated devices.

http://www.talkingelectronics.com/projects/MOSFET/MOSFET.html

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SCR and Triac

SCRs can be used in ACV output modules but Triacs are more commonly used as the switching device in PLC/PAC ACV output modules

GateCathode

Anode

Gate

Main Terminal 1

Main Terminal 2

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SCR and Triac Usage Review

One of the many applications for SCRs and Triacs is for light dimming and simple motor control. They are also used as AC voltage switches.

A Triac in its basic form is nothing more than two SCRs in parallel, back-to-back, with their gates connected together.

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SCR Usage – Light Dimmer

Representation of a lamp dimmer circuit using an SCR.

An SCR will only conduct on one half of the sine wave.

ACV

Zero CrossingDetector

Adj. FiringAngle

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SCR Usage Review

Waveforms across the lamp at different firing angles. Firing at different angles changes the effective AC

voltage across the lamp (load).

Fired at 30° Fired at 90°

Fired at 135°

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Triac Usage – Light Dimmer

Representation of a lamp dimmer circuit using a Triac.

A Triac will conduct on both halves of the sine wave.

ACV

Zero CrossingDetector

Adj. FiringAngle

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Triac Usage Review

Waveforms across the lamp at different firing angles. Firing at different angles changes the effective AC

voltage across the lamp (load).

Fired at 30° Fired at 90°

Fired at 135°

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AC Effective Voltage (FYI)

SCRs and Triacs change the effective voltage seen by a load.

Power calculations based upon a voltage midway between one peak and zero are not correct because AC voltage generally changes sinusoidal from zero to peak, rather than linearly as in DCV.

The voltage value that gives the correct result is called the Effective Voltage because it has the same effect on a power calculation as does a DC voltage of the same value.

Effective Voltage is equal to the square root of the mean value of the squares of all the instantaneous values of an AC voltage. Because of that, Effective Voltage is also known as the Root Mean Square or RMS Voltage.

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AC Voltmeters (FYI)

AC voltmeters read the AC voltage in one of three ways: Average Root Mean Square (RMS) True RMS

Average responding voltmeters simply use a diode to rectify the AC signal being measured and read the equivalent DC voltage. Most VOMs use this method for ACV measurements. (Not very accurate on non-sinusoidal waveforms).

RMS voltage is a function of power and an RMS meter uses electronics to simulate an AC power measurement making the ACV measurement more accurate.

True RMS voltage is also a function of power but also takes into consideration the heating characteristics of the ACV. True RMS voltmeters use a sophisticated µP based calculation that will mimic a bolometer by calculating the area under the curve. This is the most accurate of ACV measurements. This measurement will include any spikes or distortion on the AC signal.

Fairly good source to learn more about measuring AC voltage: http://www.allaboutcircuits.com/vol_2/chpt_1/3.html

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Inductive Flyback and Protecting the PLC/PAC

+Vac+Vdc

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Photoelectric Sensing

Photoelectric Sensor An electrical device that responds to a change in the intensity of

the light falling upon it. Photocell

A photocell is a device that changes resistance when it is exposed to light. This change in resistance can then be detected to trigger a response. The earliest method of photoelectric sensing used a photocell to sense light change.

Non-modulated The earliest photo sensors consisted of an incandescent light

bulb and a photocell. The gain of the non-modulated sensor is limited to the point at which

the receiver recognizes ambient light. This type of sensor is only powerful if its receiver can be made to

see only the light from its light source (emitter). What are some advantages and disadvantages to this type of

sensor?

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Ambient Light Receiver

Ambient light receivers are non-modulated type photoelectric sensors that are still in frequent use.

Applications for such devices could be: Detecting red-hot metal or glass that emit large

amounts of infrared light. As long as these materials emit more light than the

surrounding light level, ambient light receivers can reliably detect these materials.

A sensor mounted under an open frame conveyor that is reading the ambient light in the room. If a box, carton or some other material passes along the

conveyor and over the sensor, it blocks the ambient light from the sensor. This change in light is used to detect the presence of an object on the conveyor.

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Light Sources (Emitters)

Light Emitting Diode (LED) A solid state device electrically similar to the diode

except that it emits a small amount of light when it is forward biased.

RED GREEN AMBER

BLUE INFRARED

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Light Sensor (Receiver)

Phototransistor A solid state device similar to a transistor except that

the base connection is made using light. These devices are widely used as photoelectric receivers.

Phototransistor

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Picture borrowed from the Banner Photoelectric Handbook

Modulated LED Sensors

LEDs can be turned on-and-off at frequencies typically in the kilohertz (KHz) range. This switching on-and-off is referred to as modulating the light.

The receiver can be tuned to this frequency so that it only sees the light signals that pulse at this frequency.

This is what gives the LED sensor its apparent power.

Picture borrowed from the Banner Photoelectric Handbook

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Photoelectric Sensing Modes

Opposed Mode Retroreflective Mode Proximity Mode

Diffused mode Divergent mode Convergent Beam mode Fixed-field (sometimes called background

suppression mode) Adjustable-field

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Opposed Mode Sensing

Picture borrowed from the Banner Photoelectric Handbook

Receiver

EmitterThe emitter is a light source

Object

Often referred to as “Direct Scanning” or “Break Beam” mode.

In this mode the emitter and receiver are positioned opposite each other so that the light from the emitter is aimed at the receiver.

An object is detected when it interrupts the “effective beam” of light between the two sensing components.

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Effective Beam

Photoelectric sensors will sense a change in light when the effective beam is completely blocked.

Effective Beam

Radiation Pattern

Field of View

Emitter Receiver

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Shaping the Effective Beam

The effective beam can be shaped by using different sized lenses on the emitter and/or receiver.

Effective Beam is:Cone Shaped

Emitter (or receiver)with large lens

Emitter (or receiver)with small lens

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Shaping the Effective Beam

Apertures can also be placed on the lenses to shape the effective beam for sensing small objects that would not normally be large enough to break the effective beam.

Picture borrowed from the Banner Photoelectric Handbook

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Retroreflective Mode

This mode is also called “reflex” mode or simply “retro” mode.

The emitter and receiver circuitry of these sensors are in the same package.

The light beam is established between the emitter, a retroreflective target and the receiver.

Just as in opposed mode sensing an object is sensed when it breaks the effective beam.

Retro Target

Object

Picture borrowed from the Banner Photoelectric Handbook

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Retroreflective Mode

The range of a retroreflective sensor is defined as the distance from the sensor to its retroreflective target.

The effective beam is usually cone-shaped and connects the periphery of the retro sensor lens to that of the retroreflective target.

A good reflector will return 3,000 times as much light as a piece of white paper. This is one of the reasons that a retroreflective sensor will only recognize the light coming from its emitter.

RetroreflectiveSensor

Radiation patternand field of view

Effective Beam

Retroreflectivetarget

Picture borrowed from the Banner Photoelectric Handbook

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Retroreflective Mode – Sensing Shiny Objects

Shiny objects can pass through a retroreflective beam. To cure this problem the sensor and reflector can be mounted to “skew” the light away from the shiny object. Only 10º to 15° is required to be effective.

Boxes with shinyVinyl wrap

Conveyor

Retro target

Skew angle >10°

ReflectedLight

RetroreflectiveSensor

>10°

Flow

Picture borrowed from the Banner Photoelectric Handbook

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Retroreflective Mode – Sensing Shiny Objects

It becomes more complicated if the shiny surface is a rounded surface where light can be reflected at unpredictable angles.

Position the sensor so that the light beam strikes the object at both a vertical and horizontal skew angle.

Picture borrowed from the Banner Photoelectric Handbook

Retroreflective target mountedat angle, parallel to sensor lens

Retroreflective sensor mounted at verticaland horizontal angle to the direction of flow

Shiny object with radii

Flow

Tilt up or downand

Rotate right or left

EmittedLight

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Retroreflective Mode – Sensing Shiny Objects

Polarizing or anti-glare filters can also be used to reduce the proxing effect on shiny objects.

Emitted Light islinearly polarized

Shiny Object

Retroreflector

Light waves that are reflected by shiny surfaceare in phase with the emitted light and are blocked by the receiver filter

Retroreflected light waves are rotated 90° by thecorner-cube reflector and will pass through the filter to the receiver

Picture borrowed from the Banner Photoelectric Handbook

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Proximity Mode Sensing

Proximity mode involves detecting an object that is directly in front of the sensor by detecting the sensors own emitted energy reflecting back from the objects surface.

There are five proxing modes: Diffused Divergent Convergent Fixed field (background suppression) Adjustable field

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Diffused Sensing Mode

This is the most commonly used photoelectric sensing mode.

In this mode, the emitted light strikes the surface of the object being sensed at some arbitrary angle.

The light is then diffused from the surface at many angles.

The receiver uses a lens, whereby it can be at some arbitrary angle and still receive a small portion of the diffused light.

Emitted Light

Received Light

Object

Picture borrowed from the Banner Photoelectric Handbook

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Divergent Sensing Mode

This is a special short range mode that does not use any lens in an effort to avoid signal loss from shiny objects.

By eliminating the collimating lens, the sensing range is shortened but the sensor is also made less dependent upon the angle of incidence of its light to the shiny surface.

Picture borrowed from the Banner Photoelectric Handbook

Object

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Convergent Beam Sense Mode

This mode is very effective for sensing small objects.

They use a lens system to focus the emitted light to an exact point in front of the sensor and also to focus the receiver to this same point producing a small, intense, well-defined sensing area at a fixed distance from the lens.

Depth of Field

Focal Point

ConvergentBeam

Sensor

Picture borrowed from the Banner Photoelectric Handbook

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Laser Diode Convergent Sensor

This type of sensor produces an extremely small, concentrated focal point.

The focal point can be in the order of 0.25mm (0.01”) in diameter at a sensing distance of 100mm (4.0”).

The narrow, sharply-defined beam of a laser diode can detect the edge of a semiconductor wafer (775m or 0.03 in.) in a wafer cassette mapping application. (A representation is shown here).

Picture borrowed from the Banner Photoelectric Handbook

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Fixed-Field (Background Suppression)

Fixed-field mode has a definite limit to its sensing range. They ignore objects beyond their sensing range regardless of the objects surface reflectivity.

Fixed-field sensors compare the amount of reflected light seen by two differently-aimed receivers, R1 and R2. A target is recognized as long as the amount of light reaching R2 is greater than or equal to the amount of light reaching R1.

A depiction of a fixed-field mode sensor is shown on the next slide.

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Fixed-Field (Background Suppression)

Picture borrowed from the Banner Photoelectric Handbook

LensesObject A Object B

Emitter

Receiver

Maximum Sensing Distance

MinimumSensingDistance

FixedSensing

Field

Senses when light received by R2 ≥ the light received by R1

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Adjustable Field Mode

Similar to fixed-field, adjustable field sensors can distinguish between objects that are various distances from the sensor.

The receiver produces two currents; I1 and I2. The ratio of the current changes as the received light signal moves along the length of the receiver element.

The sensing cutoff distance is directly related to the ratio of the two currents which are adjustable using either electronic or mechanical adjustments.

Picture borrowed from the Banner Photoelectric Handbook

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Sensor Adjustments

Photoelectric sensors need to be properly aligned with the target whether it is a reflector or the object being sensed. The alignment is usually accomplished by mechanically orienting the sensor and/or the target.

Some sensors have “sensitivity” adjustments to adjust the “gain” of the sensor. This adjustment is made such that the sensors output ‘just’ turns on/off when the object to be sensed is within the sensing range.

Excessive gain is a measurement that may be used to predict the reliability of any sensing system. It is the measurement of the sensing energy falling onto the receiver element of a sensing system over and above the minimum amount required to just operate the sensors amplifier.

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Sensor Output Operating Modes

Light Operated The sensor output will energize (turn ON)

when the receiver sees light. Dark Operated

The sensor output will energize (turn ON) when the receiver sees an absence of light (darkness).

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Sensor Response Time

The response time of a sensor is the maximum amount of time required for the sensor to respond to a change in the input signal (sensing event). It is the time between the leading or trailing edge of a sensing event and the change in the sensors output.

Response time can be calculated and will be different depending upon the type of object being sensed and how the object is moving (axial, radial direction or rotary).

The formulas for calculating the response time can be found in the manufacturers specification sheets or in the manufacturers product catalog.

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Training Panel Opposed Mode Sensors

Make adjustments to the photoelectric sensors on the PLC/PAC training panel.

Banner Engineeringhttp://www.bannerengineering.com/en-US/

SM31E & SM31Rhttp://www.bannerengineering.com/en-US/support/partref/25623

Data Sheethttp://info.bannerengineering.com/xpedio/groups/public/documents/literature/03560.pdf

Installation Guidehttp://info.bannerengineering.com/xpedio/groups/public/documents/literature/69943.pdf

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Training Panel Fiber Optic Sensors

Use the Internet and look up the specifications and data sheets for the fiber optic sensor.

There are two parts to this sensor, look up both parts Sensor body Power block

Read through the data sheets and attempt making some of the adjustments. (The sensors on the training panel are fairly “beat-up” from use, so don’t get frustrated if the adjustments do not work perfectly).

When you are finished, the sensor should be “ON” when the motor wand is present and “OFF” when it’s not present and the alarm output should be “ON (N/C)” unless an alarm condition exists.

When you are finished, make sure all the sensors have their covers reinstalled and the fiber optic sensor is in “Light Mode” and the opposed mode sensors are in “Dark Mode”.

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Inductive Proximity Sensors

Inductive proximity sensors are used to sense metal objects.

The sensing distance is usually specified in millimeters and varies with the size of the sensor. The smaller the sensor, the closer the object to be sensed must get to the sensor. As the sensor gets larger the object sensing distance becomes further.

Operationally they are solid state devices with no moving parts. They consist of a:

coil high-frequency oscillator detector circuit solid state output

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Inductive Proximity Sensors

Operationally, a high-frequency field is generated in a coil mounted in the nose of the sensor and directed from the sensing surface of the sensor.

When a metal object enters the high-frequency field, eddy currents are induced into the surface of the target object.

These eddy currents cause a lose of energy in the high-frequency oscillator to occur and the amplitude of the oscillator reduces.

The detector circuit detects the reduction in amplitude of the oscillator and energizes the output circuitry to turn the sensor ON.

Oscillator Detector Output

Target

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Inductive Prox. Sensor – Shielded vs. Non-Shielded

Shielded sensor construction includes a metal band that surrounds the ferrite core and coil of the sensor. The band helps to bundle or direct the electro-magnetic field to the front of the sensor.

Non-shielded sensors do not have this metal band and therefore can be sensitive to sensing objects on the sides of the sensor.

Shielded sensors can be safely mounted in metal panels or metal brackets whereas non-shielded sensors require a metal free area around the face of the sensor.

Spacing of adjacent or opposing sensors must be taken into consideration due to the possible interference of the electro-magnetic fields generated. To avoid this problem always leave at least 2-sensor diameters, center-to-center, between adjacent or opposing sensors.

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Mounting Inductive Proxs.

When mounting inductive prox. Sensor side-by-side or face-to-face, there needs to be at least two sensor diameters between them so that the magnetic field emanating from the sensors do not interfere with each other causing the possibility of the sensors being ON all the time.

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Inductive Prox. Sensor – Sensing range

The normal sensing range of the different sensors is basically a function of the diameter of the sensing area or sensing coil. The shape of the target and the alloy of the metal will also affect the actual operating range.

Correction factors need to be applied to non-ferrous targets and are nominal values.

The table below lists some of these correction factors.

Sensing range multipliers Shielded Non-ShieldedAluminum (foil) approx. 1.00 1.00Stainless steel (alloy dependent) 0.35 to 0.65 0.50 to 0.90Brass 0.40 0.55Aluminum (massive) 0.30 0.55Copper 0.25 0.45

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Hysteresis

Hysteresis is the distance between the operating points of an inductive proximity sensor when the target is approaching the face of the sensor and the release point when the target is moving away from the sensor.

As the target approaches the sensor it must always get closer to the sensor to make the sensor turn ON then to make it turn OFF when it is moving away from the sensor.

The following slide demonstrate the hysteresis.

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Hysteresis – Axial approach

When the target approaches the sensor in an axial manner the sensor will turn ON when the target reaches the sensors prescribed sensing distance.

When the target is leaving the sensor the target must be moved further away from the sensor then the prescribed sensing distance for the sensor to turn OFF.

TargetAxial approach

Switch point when leaving Sensor turns OFF

Switch pointwhen approaching Sensor turns ON

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Hysteresis – Radial approach

When the target approaches the sensor in a radial manner the target must move further in front of the sensor to turn it ON than it has to move away from the sensor to make the sensor turn OFF.

Target

Radial approach

Sensor ON when target approaches

Sensor OFF when target leaves

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Capacitive Sensors

Capacitive sensors will sense any object that gets within their sensing range.

They can sense paper, wood, metal, liquid, powders, etc. They are one of the few sensors that are approved by

the Food and Drug Administration (FDA) to come into direct contact with consumable food products.

Oscillator Detector Output

Target

A

C

C

B

B

CB

AFront View

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Capacitive Sensors

The active element is formed by two metallic electrodes positioned much like an “opened” capacitor.

Electrodes A and B are placed in a feedback loop of a high frequency oscillator.

When no target is present, the sensors capacitance is low making the oscillator amplitude small.

When a target approaches the face of the sensor, the capacitance increases resulting in an increase in amplitude of the oscillator.

This amplitude increase is detected by the detector and output of the sensor is turned ON or OFF.

Oscillator Detector Output

Target

A

C

C

B

B

CB

AFront View

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Capacitive Sensors

Capacitive sensors have a compensation adjustment. Electrode C is the compensation electrode. The adjustment can null the affect of water droplets, humidity, dust,

etc. from affecting the operation of the sensor. In practice the compensation can literally be adjusted to “see

through” objects to another object. As an example, the sensor could be adjusted to read the ink in a felt tip pen after the cap has been placed on the pen. (Actual process at Crayola)

Oscillator Detector Output

Target

A

C

C

B

B

CB

AFront View

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Sensor Connections

Sensors come in many connection configurations. Always read the manufacturer wiring specifications before connecting a sensor. Listed are the three most common configurations:

4-wire Sink or Source Some of these sensors can be wired as either sink or source.

Not all 4-wire sensors can be wired in either polarity. Some 4-wire sensors can offer NO and NC operation and/or an alarm output, etc.

3-wire Sink or Source These sensors are specified as either sink or source when

they are purchased. The polarity can not be changed. 2-wire Sink or Source

These sensors can be wired as either sink or source and are becoming very popular because of their simplicity.

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Sensor Connections

Sensor connections vary not only between manufacturers, but within the same manufacturer. Always read the manufacturers wiring specifications before connecting a sensor into the circuit.

Wire color coding is sometimes used to identify the sensor connections. The two wires that are most in common across manufacturers are the power connections. Remember…sensors are solid state devices and therefore require power to operate.

Brown wire – +VDC usually 24VDC Blue wire – VDC common

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Interpreting Sensor Wiring Diagrams

These wiring diagrams are from the Turck sensor catalog for one particular 3-wire inductive proximity sensor.

Note how the polarity is designated.

Sink sensors supply the VDC common to the load when the switch is closed.

Source sensors supply the +VDC to the load when the switch is closed.

The load in our case would be the PLC input module.

NPN (Sinking)

PNP (Sourcing)

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Interpreting Sensor Wiring Diagrams

This is a wiring diagram from the Turck sensor catalog for one particular 2-wire inductive proximity sensor.

Note how the polarity is designated.

Two wire sensors can be wired as sink or source.

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Interpreting Sensor Wiring Diagrams

These wiring diagrams are from the Turck sensor catalog for one particular 4-wire inductive proximity sensor.

Note how the polarity is designated.

This sensor has one pole, a normally open (N.O.) and a normally closed (N.C.) contact. (SPDT)

NPN (Sinking)

PNP (Sourcing)

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Interpreting Sensor Wiring Diagrams

These wiring diagrams are from the Turck sensor catalog for one particular 4-wire inductive proximity sensor.

Note how the polarity is designated.

This sensor have one pole, a normally open (N.O.) and normally closed (N.C.) contact. (SPDT)

NPN (Sinking)

PNP (Sourcing)

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Interpreting Sensor Wiring Diagrams

This wiring diagram is from the Banner Engineering manual for a particular 4-wire sensor.

This sensor is Bipolar, meaning that a sink or source load can be switched depending upon which lead, the white or black, that is connected to the load.

White – Sink connection Black – Source connection

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Interpreting Sensor Wiring Diagrams

These diagrams are of a Keyence photo – electric sensor.

This is an example of why the manf. data sheets are required.

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I/O MODULES ARE AVAILABLE IN MANY DIFFERENT CONFIGURATIONS

PLC/PAC Module Wiring

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I/O Module Wiring

PLC/PAC I/O modules are available in many different wiring configurations: The entire module is either sink or source and

uses one I/O power source. The module is split in two halves where one half

can be sink and the other half can be source or both halves can be sink or source. When used split, two different I/O power sources can be used.

The module is split into more than two halves where each section can be independent from the others or can be combined into one section.

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Single Section Module

This is module is a single section module. The polarity (sink or source) of a single section module is determined by the manufacturer and cannot be changed. All I/O must be capable of operating from the same power source.

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Split Module – 2 Sections

Group 0 Group 0

Group 1 Group 1

This module is split into 2-sections. The 2-sections are the same polarity, (source), but each section can be powered from a different power source.

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Split Module – 4 Sections

Group 0 Group 0

Group 3Group 3

Group 1 Group 1

Group 2 Group 2

This module is split into 4-sections. The 4-sections are the same polarity, (sink), but each section can be powered from a different power source.

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Split Module – 2 Sections

This module is split into 2-sections. Each section can be wired as either sink or source and use different power sources. Also, terminals CA and CB can be jumped and the entire module can be wired as either sink or source.

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Class Wiring Exercise

Instructor led wiring exercise Equipment

1) Sensor, any polarity 1) Mechanical switch and actuator 1) Lamp assembly or illumination block Wire Various hand tools Disconnect the pre-wired I/O cables.