SensorBasics Level I
-
Upload
julie-soosai -
Category
Documents
-
view
216 -
download
0
Transcript of SensorBasics Level I
-
7/31/2019 SensorBasics Level I
1/68
Training Series: Level I
Introduction to Sensors
-
7/31/2019 SensorBasics Level I
2/68
Course Topics
Sensors Definition
Sensor Building Blocks
Electrical Interface
Tell me about it:
Sensing Technology
I see it: Housings
Looks are everything:
Training Series: Level I
Level IIIAdvance Problem Solving
Level IIProducts andApplications
Level ISensorBasics
-
7/31/2019 SensorBasics Level I
3/68
Training Series: Level I
Sensor Definitions
-
7/31/2019 SensorBasics Level I
4/68
What is a Sensor?
Used in Industrial Automation:
Electrical device capable of identifyingchangewithin an automated process.
Sometimes
Sensor = Switch
Sensor Definitions
-
7/31/2019 SensorBasics Level I
5/68
Sensor Uses
Sensors in our world
Automatic opening doors
Grocery check-out conveyer shut-off
Safety sensors on garage doors
Sensors in Manufacturing
Part position verification
Counting products
Liquid level control
Quality control inspection
Personal safety systems
Sensor Definitions
-
7/31/2019 SensorBasics Level I
6/68
Sensor Building Blocks
The three major components:
The sensing sideFront-end
Housing
The electrical sideBack-end
Sensor Definitions
-
7/31/2019 SensorBasics Level I
7/68
Building Block Concept
Sensor Definitions
Sensingtechnology
Electricalinterface
Housing
most any
most any
most any
-
7/31/2019 SensorBasics Level I
8/68
The Building Blocks
Front-end - Sensing
Five technology choices:
Inductive
Optical
Capacitive
Magnetic
Mechanical
Selection base on: Application
Sensor Definitions
-
7/31/2019 SensorBasics Level I
9/68
The Building Blocks
Back-end Electrical
Options:
Electrical voltage AC/DC
DC
Output type
Discrete (on-off, like a switch) Analog
Selection base on: Control System
Sensor Definitions
-
7/31/2019 SensorBasics Level I
10/68
The Building Blocks
The Sensors Housings
Material Options:
Metal (nickel-plated brass) Stainless steel
Aluminum
Plastic
Shape (mounting style):
Tubular
Block
Selection base on: Environment
Sensor Definitions
-
7/31/2019 SensorBasics Level I
11/68
The Building Blocks
and the real world
Housing
Environment
Sensor Definitions
-
7/31/2019 SensorBasics Level I
12/68
Training Series: Level I
Electrical Interface
-
7/31/2019 SensorBasics Level I
13/68
Electrical Interface
Divided into 2 areas:
Operating voltage
Output signal type
Electrical Interface
Power
Signal
-
7/31/2019 SensorBasics Level I
14/68
Output Signal Types
Discrete
ON or OFF
YES or NO
Analog
Speed control
Position information
MIN MAX
Electrical Interface
Signal
-
7/31/2019 SensorBasics Level I
15/68
Operating Voltage
Direct Current (DC)
Current flows in only
ONE direction Safe, easy-to-handle
power source
Alternating Current (AC)
Current changes direction
60 times a second Readily available
Electrical Interface
Power
-
7/31/2019 SensorBasics Level I
16/68
Basic Electrical Principals
What is electricity?
Interesting fact: Electron flow is similar to water flow
We will use this analogy during our class
Electrical Interface
Flow (current) or potential flow(voltage) of electrons
-
7/31/2019 SensorBasics Level I
17/68
Basic Series Circuit
Using Water Analogy:
Water Tank
Water Valve
Hydro motor
PotentialFlowing
Electrical Interface
-
7/31/2019 SensorBasics Level I
18/68
Basic Series Circuit
Electronics:
PotentialFlowing
+
-
BatterySwitch
Electric Motor
Basic ON or OFF operation
Electrical Interface
-
7/31/2019 SensorBasics Level I
19/68
A discrete
Sensor is a Switch
Electronics
Sensing Side
Front-end
Electronics
Power WiresSwitch
Electrical Interface
-
7/31/2019 SensorBasics Level I
20/68
Electronics
Basic Sensor Circuit
Sensors with relay output
+
-
Unlike a switch,sensors requirepower to operate
Electrical Interface
-
7/31/2019 SensorBasics Level I
21/68
Types ofdiscrete
electrical outputs
Sensors of today use Solid-State
outputs, not mechanical relaysToday Yesterday
PNP, 3-wire Relay
NPN, 3-wire
AC/DC, 2-wire
Electrical Interface
-
7/31/2019 SensorBasics Level I
22/68
The NPN & PNP outputFunctions similar to a switch,
But current only flows in one direction
PNP
Transistor MechanicalSwitch
Electrical Interface
-
7/31/2019 SensorBasics Level I
23/68
The Different Transistors
What direction do you want current to flow?
NPNAlso called Sinking
Electrical Interface
PNPAlso called Sourcing
+--+
-
7/31/2019 SensorBasics Level I
24/68
PNP, 3-wire
1
4
+
PNP Output
3 -
Load
Standard diagram formAs shown in our catalog
The Sensor
The LoadConnector
Pins
Electrical Interface
-
7/31/2019 SensorBasics Level I
25/68
PNP, 3-wire
1
4
+
PNP Output
3 -
Load
Watching the current flow
Sensors Power
Output Signal
Electrical Interface
-
7/31/2019 SensorBasics Level I
26/68
1
4
+
NPN Output
3 -
Load
NPN, 3-wire
Watching the current flow
Sensors Power
Output Signal
Electrical Interface
-
7/31/2019 SensorBasics Level I
27/68
1 ~
3 ~
Load
The 2-wire AC/DC outputFunctions similar to a switch,
But with a small leak
Sensors PowerSupply from leakage current
Output SignalTriac
Electrical Interface
-
7/31/2019 SensorBasics Level I
28/68
Quick Reference:
wiring PNP & NPN
N P NP N P
+
-
Load
Positive
Negative
Sensor is PNP
Electrical Interface
-
7/31/2019 SensorBasics Level I
29/68
If given a choice, which discretesensortype should I choose?
PNP or NPN, 3-wire- Fewer interface
problems- Largest selection- Lowest unit costs
AC/DC, 2-wire- Many interface issues- Smaller selection- Susceptible to noise
1st CHOICE
2nd CHOICE
1
4
+
3 -
Load
1 ~
3 ~
Load
Electrical Interface
-
7/31/2019 SensorBasics Level I
30/68
Normally Open (NO)
vs.
Normally Closed (NC)Identifies the non-active state (target not present)of the sensor
Electronics
+
-
Normally Open
Is it off (open)?
Is it on (closed)?
Electrical Interface
-
7/31/2019 SensorBasics Level I
31/68
Normally Open (NO)
vs.
Normally Closed (NC)Identifies the non-active state (target not present)of the sensor
Electronics
+
-
Is it off (open)?
Is it on (closed)?
Normally Closed
Electrical Interface
-
7/31/2019 SensorBasics Level I
32/68
Analog OutputsUnlike a discreteoutput with two defined states,analog signals have an infinite number of states.
Discrete
Analog
On
Off
Voltage
Time
Max
Min
Voltage
Time
Electrical Interface
-
7/31/2019 SensorBasics Level I
33/68
Analog UsesTo provide absolute measurement orposition information
MeasurementPosition
Electrical Interface
-
7/31/2019 SensorBasics Level I
34/68
Analog Applications!
What can you do with measurement information? Measure thickness
Position feedback
Measure tool wear
Null out machine wear Null out thermal
expansion
Verify die position
Verify bend radius
Part profiling
Stack height
Spool diameter
Rotational position
Liquid level
Sort parts Determine part
orientation
Measure vibration
Measure straightness
Hydraulic or pneumaticcylinder position
Expanding
possibilities
Electrical Interface
-
7/31/2019 SensorBasics Level I
35/68
-
7/31/2019 SensorBasics Level I
36/68
Analog Information
The many forms for representingmeasurement or position information
10
0
10
-10
5
-5
20
0
20
4
Voltage
Current
Digital Pulse
Electrical Interface
-
7/31/2019 SensorBasics Level I
37/68
Analog Voltage
Information contained in varying voltage
Maximum Voltage
0 1098
7654321
Measurement
Half Voltage
0 1098
7654321
Measurement
Water Analogy Volt Meter
Electrical Interface
-
7/31/2019 SensorBasics Level I
38/68
Analog Current
Information contained in varying Current
0 1098
7654321
Measurement
0 1098
7654321
Measurement
Maximum CurrentHalf Current
Water Analogy Current Meter
Electrical Interface
-
7/31/2019 SensorBasics Level I
39/68
Digital Pulse
Information contained in digital pulse timing
100.00Maximum measurementHalf wayMinimum measurement
50.000.00Pulse WidthMeter
Start/Stop
Electrical Interface
Measurementrange
Measurementrange
-
7/31/2019 SensorBasics Level I
40/68
Electrical Interface
REVIEW Operating voltage: Sensor Power
DC: Safest
AC: Most available Output signal types
Discrete PNP, 3-wire
NPN, 3-wire
AC/DC 2-wire
Analog Voltage
Current
Digital pulse
Electrical Interface
Power
Signal
Training Series: Level I
-
7/31/2019 SensorBasics Level I
41/68
Training Series: Level I
Sensing Technologies
S i T h l i
-
7/31/2019 SensorBasics Level I
42/68
Sensing Technologies
Non- Contact
No physical contactwith target
Preferred method forsensing endproducts
Contact
Contact with target
Simplest methodavailable
Sensing Technologies
S i T h l i
-
7/31/2019 SensorBasics Level I
43/68
Contact Sensing
Mechanical switch
Contact with plunger
opens electricalcontacts
Sensing Technologies
S i T h l i
-
7/31/2019 SensorBasics Level I
44/68
Non-Contact
Popular sensing technologies Inductive Sensors
Metal targets
Optical SensorsTarget capable of reflecting or blocking light
Capacitive Sensors
Liquids/solids Magnetic Field Sensors
Magnets
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
45/68
Inductive When voltage is applied, an electromagnetic field is
generated and extends out the face of the sensor.
When metal enters the sensing zone, an eddycurrent is induced in the metal.
The change in eddy current is detected and thesensors output is energized.
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
46/68
Two basic Sensing types Flush mount
Shorter range
Sensor can be buried in metal
Non-flush mount
Longer range
Sensor can NOT be buried in metal
Inductive
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
47/68
OpticalRegardless of the operating mode, all opticalsensors share the same operating principle:
Light emitter Visible red Laser Infrared
Light receiver
OperationEmits a light beam thendetects or measures changes
in received light.
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
48/68
Optical
Optical sensors offer three mainsensing modes
Thru-beam
Retroreflective
Diffuse
Note: There are other sensing modes available, but theyare covered in other courses.
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
49/68
Optical: Thru-Beam Separate emitter and receiver
Beam-break operationTarget blocks beam
Emitter Receiver
Great for long range and dirty environments
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
50/68
Optical: Retroreflective Emitter and receiver in one unit Requires a reflector Beam-break operation
Target block light beam
ReflectorEmitter
Provides good range in well defined area
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
51/68
Emitter and receiver in one unit Convenient stand-alone design Beam-make operation
Light reflects off target
Optical: Diffuse
Simple point and shoot operation
Target
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
52/68
Capacitive Detects target based on density
Simple point and shoot operation
Target
Electrostatic field established
Target detected when field properties change
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
53/68
Magnetic Detects magnetic field Magnetic field can travel through aluminum
Used extensively with pneumatic cylinders
Magnet
N
S
Sees through aluminum
Sensing Technologies
Sensing Technologies
-
7/31/2019 SensorBasics Level I
54/68
Sensing Technologies
Head-to-HeadMechanical:
Inductive:
Optical, Thru-beam:
Optical, Retro:
Optical, Diffuse:
Capacitive:
Magnetic:
Popular, simple
Rugged, cost-effective
Long range
Mid range
Short range
Liquid & bulk targets
Pneumatic cylinders
Sensing Technologies
Training Series: Level I
-
7/31/2019 SensorBasics Level I
55/68
Housings
Housings
-
7/31/2019 SensorBasics Level I
56/68
Housing Function
Protection from environment
Mounting provisions
Electrical connection
Housings
Housings
-
7/31/2019 SensorBasics Level I
57/68
Protection from
environment Multiple degrees of protection liquids IP65: Protects against water mist
IP67: Protects against temporary immersion
IP68: Protects against continuous immersion
Multiple level of physical abuse
Metal housing
Plastic housing
Housings
Housings
-
7/31/2019 SensorBasics Level I
58/68
Mounting Provisions
Depends on shape of housing
Tubular
Popular for short range sensors
Range adjustments made by moving sensor inand out
Block
Popular for optical sensors
Easy to align horizontally and vertically
g
Housings
-
7/31/2019 SensorBasics Level I
59/68
Inductive Sensor
Tubular HousingsEasy mounting and range adjustment
Optical Sensor
Capacitive
Magnetic
g
Housings
-
7/31/2019 SensorBasics Level I
60/68
Block Housings
Providesthru-holesfor mountingbolts
Allows foreasy beamalignment
Inductive Sensor
Optical Sensor
BOS-SR2
g
Housings
-
7/31/2019 SensorBasics Level I
61/68
Combination HousingsCombinationof tubular andblockhousings
Inductive Sensor
Optical Sensor
g
Housings
-
7/31/2019 SensorBasics Level I
62/68
Application Specific
ShapesInductive Sensor
Optical Sensor
Magnetic
HydraulicCylinder
RingSensor
ValvePosition Clamp
Position
SlotSensors
WindowsFiber-optics
PneumaticCylinders
g
Housings
-
7/31/2019 SensorBasics Level I
63/68
Electrical Connection
Cable Out version
Economical: no additional cable to
purchase Difficult to replace sensor
Connector version
Cost: must purchase mating cable Much easier to replace sensor
Housings
-
7/31/2019 SensorBasics Level I
64/68
Cable Connection Options
Cable Lengths
Standard lengths: 2m, 3m & 5m
Jacket Material PVC: Standard, low cost jacketing
PuFlex: For flexing applications
Housings
-
7/31/2019 SensorBasics Level I
65/68
Connector Options
Industry standard connector sizes:
Micro (M12)
Most popular, mid-size
Available in 3, 4, 5 and 8 pins
Nano (M8)
Smallest size
Available in 3 and 4 pins
Mini
Largest size
Available in 3 and 4 pins
Housings
-
7/31/2019 SensorBasics Level I
66/68
Sensor Housings
REVIEW Protection from environment
IP65, IP67, IP68
Mounting provisions Tubular, Block, Combination, Application
specific shapes
Electrical connection Cable out and connectors
Sensors Definitions
-
7/31/2019 SensorBasics Level I
67/68
Sensor Fundamentals
Housing
Environment
Questions & Answers
Training Series: Level I
-
7/31/2019 SensorBasics Level I
68/68
Sensor Basics