GENERAL INFORMATION
®
The Bourns EN model is a self-contained rotary optical encoder.
Bourns encoder output signals are square wave digital pulses which
do not require debounce circuitry. Both features make it possible
to significantly reduce the memory overhead, wiring and wiring inter-
connects required by other types of control devices.
It produces a 2-bit quadrature signal which is suitable for digital
systems where both magnitude and direction of adjustment must
be provided. The EN encoder is ideal for use as a digital panel
control or as a position sensing device in applications where long
life, reliability, high resolution and precise linearity are critical.
EN optical encoders offer a useful rotational life of from 10 million to
200 million shaft revolutions, making them ideal for extended service
applications. The Bourns encoder is also compact and well suited for
situations where the available space is limited.
The EN series encoder converts rotary input into electrical signals
which can be used by microprocessors without A/D conversion.
EN - Rotary Optical Encoder
How To Order
BOURNS EN SERIES OPTICAL ENCODER
E N C 1 J - D 2 8 - L 0 0 1 2 8 L
ANTI-ROTATION
LUG POSITION
SHAFT LENGTH*
Code Description
RoHS IDENTIFIER
Code Description
Code Description
16
20
24
28
1/2 " Long
5/8 " Long
3/4 " Long
7/8 " Long
L
Compliant
D
J
None
Blank Non-Compliant
Non-compliant versions are
available, but not recommended
for new designs.
9:00 Position
Rear Mount-
ing Bracket
P
TERMINAL****
SWITCHING
CONFIGURATION
Code Description
CONFIGURATION
Code Description
RESOLUTION
L
R
M
Axial, Multi-
Purpose Pin
Radial, Multi-
Purpose Pin
Axial, Ribbon
& Connector
10 “
Cycles Per
Channel A
Leads
Code Revolution
00025
00050
00064
00100
00125
00128
00200
00256
ꢀꢀ25
ꢀꢀ50
ꢀꢀ64
100
125
128
200
256
1
Channel B
By 90 °
(Clockwise
Rotation)**
Code 1
N
W
Y
Radial, Ribbon
& Connector
10 ”
Switching
With Index
Channel***
2
Axial, Ribbon
10 “ -
No Connector
Radial, Ribbon
10 ” -
No Connector
SHAFT STYLE
Use With
Code Description
Bushings (Code)
ꢀꢀA, S
B
D
C
1/4 " Dia., Plain End
1/8 " Dia., Plain End
1/4 " Dia., Single
Flatted
C, T, W
A, S
BUSHING CONFIGURATION
Code Description
A
C
S
3/8 "D X 3/8 "L Threaded
1/4 "D X 1/4 "L Threaded
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)
*
Shaft length measured from mounting surface.
** 25 and 50 PPR is reversed (Channel B leads Channel A).
*** Only available with 50, 64, 100 and 128 PPR.
REV. 02/12
*** Standard ribbon cable is 10 " long. Consult factory for other lengths.
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.