Optical Encoders
174
optical encoder - low cost
Key features
•
two channel quadrature
•
square wave signal
•
high reliability
•
bushing and servo mount styles
•
small size
•
CMOS and TTL compatible
type DP21 series
The DP21 may be used as a
manual input device for
digitally controlled equipment
such as CAD/CAM systems,
electronic test equipment,
medical electronics,
instrumentation, computer
peripherals and machine tools.
Typically, the encoder drives an
up/down counter and it is used
to control one or more
functions. Common
applications include motor
speed control, cursor control,
frequency setting, amplifier
gain adjustment and table
positioning.
•
long life (10,000,000 revolutions)
•
attractively priced
Specification
Electrical
Output:
Supply Voltage:
Supply Current:
Insulation Resistance:
Rise/Fall Time:
Shaft RPM (Ball Bearing):
2 bit grey code, channel A leads channel B by 90° (clockwise)
5V DC
26mA maximum
1000 M Ohm
200 nano seconds
5000 rpm maximum
Pulse Width (Electrical):
180° ± 45° typical each channel
Pulse Width (Index Channel): 360° ± 90°
Mechanical
Rotation Angle:
Torque (Starting & Running):
A & C Bushings:
W, S, T Bushings:
Rotational Life.
A & C Bushings:
W, S, T Bushings:
360° continuous
10.5mNm maximum
0.7mNm maximum
10,000,000 revolutions (300 rpm maximum)
200,000,000 revolutions (3000 rpm maximum)
Encoders
Environmental
Operating Temperature:
-40°C to +85°C (256 PPR -20°C)
Quadrature Output Table
4.0V
0.8V
4.0V
Channel B
0.8V
Index Channel 4.0V
0.8V
(Optional)
Channel A
(Min)
(max)
(Min)
(max)
(Min)
(max)
1
0
1
0
1
0
sales action desk
(01793) 611666
sales fax line
(01793) 511513
Meggitt Citec
optical encoder - low cost
175
Dimensions
Bush Style C
type DP21 series
The DP21 can also be used for
position sensing applications.
A gear can be placed on the
encoder shaft allowing it to be
interfaced with a moving
table, rotating shaft, stepping
motor, etc... Movement of the
encoder shaft is translated
into a 24-bit quadrature signal,
which (when fed through a
logic circuit), allows the
microprocessor to determine
changes in position. As a
position feedback device, the
DP21 applications include
machine tools, plotters and
robotics.
Bush Style A
Bush Style S
(Ball Bearing)
Bush Style T
(Ball Bearing)
Servo Mount Style W
(Ball Bearing)
How To Order
DP21EN
Common Part
Encoders
C
Bushing Configuration
A -
3
/
8
"D x
3
/
8
"L Threaded
C -
1
/
4
"D x
1
/
4
"L Threaded
S -
3
/
8
"D x
3
/
8
"L Threaded
(Ball Bearing)
T -
1
/
4
"D x
3
/
8
"L Threaded
(Ball Bearing)
W - Servo Mount
7
/
8
"D
(Ball Bearing)
I
Switch Configuration
I - Leads Channel B By
90° (Clockwise)
J
Lug Position
D - None
J - 9:00 Position
DP21EN
B
Shaft Style
Bush
Code
20
Shaft Length
16 -
1
/
2
" Long
20 -
5
/
8
" Long
28 -
7
/
8
" Long
L
Terminal Configuration
L - Axial,
Multi-Purpose
Pin
00128
Resolution
00064
00100
00128
00256
-
-
-
-
64ppr
100ppr
128ppr
256ppr
B - /
4
" Dia. Plain End (A,S)
D -
1
/
8
" Dia. Plain End (C,T,W)
1
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ELECTRONIC
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