Upload
airton58
View
39
Download
1
Embed Size (px)
Citation preview
se
le
cti
on
aid
Find the right encoder for your application.
selection Guide for encoders
2 s e l e c t i o n G u i d e f o r e n c o d e r s | s i c k - s t e G M a n n 2 0 0 9 - 0 8
incremental, absolute, linear... Which encoder is right for your application?
Often the differences between two encoders seem to be small. This guide will help you find these differences quickly and easily, enabling you to choose the right encoder product family.
What is the difference between ...?
and between ...?
incremental and absolute
•Counts pulses from 1 to n•Reference run (zero pulse) necessary to obtain absolute
position value• The number of pulses defines the resolution
•Measures the absolute position from 1 to n•Every measuring step is defined by a unique (absolute)
code pattern• The number of steps defines the resolution
absolute singleturn and absolute Multiturn
•Variant of an Absolute Encoder•Measures the absolute position from 1 to n within one
revolution
•Variant of an Absolute Encoder•Measures the absolute position from 1 to n within one
revolution• In addition measures the number of revolutions
Wire draw encoders and linear encoders
•Measures lengths between A and B•Consists of a Rotary Encoder and a wire draw mechanism• The wire is mounted to the moving part• The encoder is fixed
•Measures lengths between A and B•Consists of read head and scale• The read head is mounted to the moving part• The scale is fixed
3s i c k - s t e G M a n n | s e l e c t i o n G u i d e f o r e n c o d e r s2 0 0 9 - 0 8
What should be measured?angle, speed, velocity or distance?
from speed monitoring to tracking products on a conveyor, sick helps you select an encoder based on the parameters that need to be measured.
angle, speed or Velocity = rotary encoders (selection guide pages 4-5)
distance = linear encoders (selection guide page 6)
absolute singleturn encoders
ARS20/25
linear encoders with scale
KH53 KH53 A L230
incremental Wire draw encoders
PKS PRF
absolute Wire draw encoders
BKS/XKS BTF
DFS60
DKS40 DKV60 DGS34/35
incremental encoders
SKM36 + fieldbus moduleAFM60 ATM60 ATM90 SRM64/50 + fieldbus module
absolute Multiturn encoders
AFS60
ARS60
DRS60/61 DRS25/26
DGS20/25 DGS21/22
DRS20/21
4 s e l e c t i o n G u i d e f o r e n c o d e r s | s i c k - s t e G M a n n 2 0 0 9 - 0 8
incremental encoders
incrementalencoders
dfs
60
dr
s60/
61
dr
s25/
26
dr
s20/
21
dG
s20/
25
dG
s21/
22
ld20
dks
40
dkV
60
dG
s34/
35
should an absolute position always be measured?
Yes
no ■ ■ ■ ■ ■ ■ ■ ■ ■How many absolute turns should be measured?
no absolute measurement ■ ■ ■ ■ ■ ■ ■ ■ ■1
2 or more
Which interface connection is required?
ttl (5 V) pulses/ Htl (10 to 30 V) pulses ■ ■ ■ ■ ■ ■ ■ ■ ■Parallel data word
ssi data word
Bus connectivity, data word
What is the maximum diameter available?
40 mm ■60 mm ■ ■ ■3.5 in ■2 in ■ ■ ■2.5 in ■ ■
What type of mounting shaft is required?
Face mount flange solid shaft ■ ■ ■ ■Servo flange solid shaft ■ ■ ■ ■ ■Square flange ■ ■ ■Blind hollow shaft ■ ■ ■ ■through hollow shaft ■ ■ ■ ■Measuring wheel ■
is a shaft diameter > 16 mm required?
Yes ■no ■ ■ ■ ■ ■ ■ ■
What resolution is required (pulses/steps)?
Max. 2,500 ■ ■ ■ ■Max. 8,192 ■ ■ ■Max. 32,768 ■> 32,768 ■
is a solution enabling program-ming by the customer required (resolution, zero-pulse …)?
Yes ■ ■ ■ ■no ■ ■ ■ ■ ■ ■ ■ ■ ■
> >>>>>>>>>>>>
>>
>>>>>>>>>
>
>>
>
>
5s i c k - s t e G M a n n | s e l e c t i o n G u i d e f o r e n c o d e r s2 0 0 9 - 0 8
absolute encoders
absolute singleturn encoders
absolute Multiturnencoders
afs6
0
ars6
0
ars2
0/25
afM
60
atM
60
atM
90
skM
36 +
fie
ldbu
s mod
ule
srM
64/5
0 +
field
bus m
odul
e
should an absolute position always be measured?
Yes ■ ■ ■ ■ ■ ■ ■ ■no
How many absolute turns should be measured?
no absolute measurement
1 ■ ■ ■2 or more ■ ■ ■ ■ ■
Which interface connection is required?
ttl (5 V) pulses/ Htl (10 to 30 V) pulses
Parallel data word ■ ■ssi data word ■ ■ ■ ■ ■ ■ ■ ■Bus connectivity, data word ■ ■ ■ ■
What is the maximum diameter available?
40 mm ■60 mm ■ ■ ■ ■ ■90 mm ■2 in ■2.5 in ■ ■
What type of mounting shaft is required?
Face mount flange solid shaft ■ ■ ■ ■ ■ ■Servo flange solid shaft ■ ■ ■ ■ ■ ■Square flange ■ ■Blind hollow shaft ■ ■ ■ ■ ■through hollow shaft ■ ■ ■ ■ ■Measuring wheel
is a shaft diameter > 16 mm required?
Yes
no ■ ■ ■ ■ ■ ■ ■ ■What resolution is required (positions/turn)?
Max. 2,500
Max. 8,192 ■ ■Max. 32,768 ■ ■ ■> 32,768 ■ ■ ■
is a solution enabling program-ming by the customer required (resolution, zero-pulse …)?
Yes ■ ■ ■ ■ ■ ■no ■ ■ ■ ■ ■ ■ ■ ■
> >>>>>>>>>>>>
>>
>>>>>>>>>
>
>>
>
>
6 s e l e c t i o n G u i d e f o r e n c o d e r s | s i c k - s t e G M a n n 2 0 0 9 - 0 8
linear encoders
incremental Wire draw encoders
absolute Wire draw encoders
linear encoders with scale
Pks
Prf
Bks
Xks
Btf
kH53
kH53
a
l230
should an absolute position always be measured?
Yes ■ ■ ■ ■ ■ ■no ■ ■
Which interface connection is required?
ttl (5 V) pulses/ Htl (10 to 30 V) pulses ■ ■HiPerface® ■ ■ssi data word ■ ■ ■ ■ ■ ■Bus connectivity, data word ■ ■ ■ ■
are there continuous mount-ing points available across the measuring length?
Yes ■ ■ ■no ■ ■ ■ ■ ■
What are the mounting tolerances?
low ■ ■ ■ ■ ■ ■ ■Medium ■ ■High ■
What measuring length is required?
up to 5 m ■ ■ ■ ■ ■ ■ ■ ■up to 40/50 m ■ ■ ■ ■ ■up to 548 m ■ ■up to 1,700 m ■
What resolution is required? 0.1 to 0.05 mm ■ ■ ■ ■ ■ ■0.025 mm ■ ■ ■0.001 mm ■
Maximum number of measuring cycles?
up to 800,000 ■ ■ ■up to 1,000,000 ■ ■Infinite ■ ■ ■
>>>>>>>>>>>>>>>>>>>>>
7s i c k - s t e G M a n n | s e l e c t i o n G u i d e f o r e n c o d e r s2 0 0 9 - 0 8
Definition of Technical Terms
accuracyDeviation between the real and the measured position
accuracy of repeatability/reproducibilityDeviationofthemeasuredvalueswhenadefinedpointisrepeatedly being approached under the same operating conditions
Baud rateSpeed of data transmission (bits/sec)
Bcd (Binary coded decimal) codeBinary presentation of a decimal number
Binary codeTwo digit numerical code consisting of 1s and 0s, which is capable of representing any integer decimal number
BitAbbreviation for “binary digit.” Smallest information unit of a binary system, whereby the values can be 1 or 0 (Yes/No decision).
dcDirect current
direction of rotationCan be clockwise (cw) or counterclockwise (ccw), as viewed from the shaft
enableControl input, by which the data outputs of absolute en-coders with parallel interface can be activated
flanges/shaftsDifferent mechanical adapters for the mounting of drive shafts to motors and gearboxes, as well as to gearwheels and pulleys
Gray codeSingle-step code. When changing from one value to the next,onlyonesingledatacodebitismodified.Worksforresolutions which can be expressed by 2n (e.g., 1024, 2048, 4096, etc.).
Gray excess codeGray code with cut-out (excess). Ensures that the single step characteristic of Gray code is maintained for resolu-tions which cannot be expressed by 2n (e.g., 360, 720, 1440, etc.).
JitterVariation of pulses during the transmission of digital sig-nals.Thepositionofthesignalflankscontinuallychange.
line driverOutput circuit which enables the use of a higher current to drive the signal over long distances
MultiturnIn addition to the singleturn data (positional information within one turn), the number of shaft revolutions (turns) is also transmitted
Protection classesDefinedaccordingtoDINVDE0470(EN60529,IEC529),are to be understood when the encoder is mounted. There are differences between protection classes for different housing styles and protection classes for shafts. The pro-tection class for housing depends mainly on the female connector being used or on the type of connector.
repeatabilityMaximum variation of the measured values produced dur-ingaminimumof5successivemovementstoadefinedposition, whereby the position is approached from the samedirectionandatafixedtemperature(accordingtoDIN 32878)
resolutionNumber of lines/steps per revolution. In case of abso-lute multiturn encoders, the resolution also includes the number of shaft turns.
shaft loadMechanical load on the encoder shaft in axial or radial direction
singleturn Positional information within one turn
speedMechanical turns of a shaft in revolutions per minute
ssiSynchronous serial interface. Standardized interface for serial data transmission.
Zero pulse (reference signal)An output signal given by an incremental encoder, which signifiestheendofonerevolution(360degreesofrotation)
Zero pulse widthLength of the marker/pulse reference
7130711/2009-08-01∙PrintedintheU.S.(2009-08)
Subj
ect t
o ch
ange
with
out n
otic
e
Handed over by:
factory automation
With its intelligent sensors, safety systems,andautoidentificationsolutions, SICK offers comprehensive solutions for factory automation.
logistics automation
Solutions from SICK automate material flowsandoptimizesortingandwarehousing processes.
Process automation
Analyzers and process instrumentation from SICK provide the best possible acquisition of environmental and process data.
our competence in the Business segments
• Non-contact detecting, counting, classifying, and positioning of any type of object
• Accident protection and personal safety using sensors, as well as safety software and services
• Automated identification with bar code reading devices for the purpose of sorting and target control in industrialmaterialflow
• Detecting volume, position, and contours of objects and surroundings with laser measurement systems
• Complete system solutions for gas analysis, dust measurement, flow rate measurement, water analysis, liquid analysis, and level measurement as well as other tasks
SICK AG | Waldkirch | Germany | www.sick.com
Worldwide presence with subsidiaries in the following countries:
australia
Belgium/luxembourg
Brasil
ceská republika
china
danmark
deutschland
españa
france
Great Britain
india
israel
italia
Japan
nederland
norge
Österreich
Polska
republic of korea
republika slovenija
românia
russia
schweiz
singapore
suomi
sverige
taiwan
türkiye
united arab emirates
usa/canada/México
Pleasefinddetailedaddressesand additional representatives and agencies in all major industrial nations at www.sick.com
sick steGMann, inc.7496 Webster street dayton, oH 45414 usa800.811.9110 or 937.454.1956 www.stegmann.com