See ST50 Series Hollow Shaft Encoders for Higher ppr and more Options

Other Shaft Encoders Available - go to ST20 Series Shaft Encoders

Digital feedback up to 1024 pulses/revolution.

Incremental Encoder

Compact incremental encoders are available with a variety of resolution and output options to give digital feedback from any rotating shaft. These 100-to-1024-line optical devices provide LSTTL 3.2 mA output standard; 16 mA (STTL) with optional amplifier circuitry.
Operating on 5 Vdc, the encoders offer resolutions of 100, 192, 200, 256, 360, 400, 500, 512 or 1024 lines per revolution. Square-wave output is in three channels-two in quadrature (90° phasing) for position/direction feedback, and a single-pulse-per-revolution index. Accurate resolution is achieved through the use of a low-inertia code wheel, low-refraction light from an LED source, and a bifurcated lens/receptor system.
These durable encoders employ rugged anodized aluminum housings to protect inner components; shafts and bearings are made of stainless steel for maximum wear resistance .
Standard models provide termination through an integral 24" ten-conductor ribbon cable with polarized connector. Units with amplifier circuitry use an eight-conductor cable, with ends stripped and tinned for immediate connection. Flange- and face-mount configurations are available.
 ST20 Series Encoder

Encoder Option Other Tachometer/Encoder Combinations Available go to PTS Series -

Offering the same resolution and output choices as the incremental encoder, the encoder option is available integrally mounted on Servo-Tek 1.135" dc tachometers and motors. The compact device adds just 1.1" (2.7", amplified) to the length of the host component.
Like the incremental encoder, electrical connections are made with a 24" ten-conductor ribbon cable (standard output), or with an eight-conductor cable, ends stripped and tinned (amplified output).

PTS Series Tachometer/Encoder

General Specifications

                            without amplifier       with amplifier*
Operating temperature       -55 to +85°C             0 to 70°C
Storage temperature         -55 to +100°C            -55 to + 100°C
Maximum velocity            12,000 rpm               12,000 rpm
Maximum acceleration        250,000 rad/sec^2        250,000 rad/sec^2

Electrical Specifications

                            without amplifier       with amplifier*
Supply voltage (ripple <  
 100 mV p-p)                4.5 Vdc minimum;         4.5 Vdc minimum;
                            5.5 Vdc typical          5.5 Vdc typical
Supply current              40 mA typical;           50 mA typical;
                            60 mA maximum            85 mA maximum
High-level voltage output   2.4 V minimum            2.4 V minimum
High level current output   -40 µA maximum           -0.4 mA maximum
Low level voltage output    0.4 V maximum            0.4 V maximum
Low-level current output    3.2mA                    16mA
Rise time**                 0.5 µs typical           0.6 µs typical
Fall time**                 0.2 µS typical           0.3 µs typical
Cable capacitance           12 pF/meter typical,     164 pF/meter typical,
                            output lead-to-ground;   output lead-to ground;
                            ribbon cable             4 twisted pairs,
                                                     shielded cable
*Other amplifiers available
**CL = 25 pF: RL = 11 k ohms.

Performance Characteristics

(with or without amplifier)

Resolution

100,192, 200, 256, 360, 400,500, 512 and 1024 lines/ revolution standard

Position error

10' typical; 40' maximum; (1 cycle = 43.2')

Cycle error

3°typical; 10° maximum (electrical degrees)

Maximum count frequency

200 kHz typical; 100 kHz minimum

Pulse width error

20° (electrical) at 25°C

Pulse width temperature coefficient

1.0 x 10^-5 typical; 2.5 x 10^-5 maximum (electrical degrees, °C x Hz)

Logic state width error

30° typical (electrical degrees at 25°C)

State width error temperature coefficient

1.0 x 10^-5typical; 2.5 x 10^-5 maximum (electrical degrees, °C x Hz)

Index pulse width

360° (electrical)

Index pulse adjustment

180° (electrical), set at factory

Mechanical Specifications

(with or without amplifier)

Moment of inertia

stand-alone: 7.783 x 10^-6 oz-in -sec^2;
option: 7.783 x 10^-6 oz-in -sec^2
(added to tach moment)

Weight

stand-alone: approx 3.5 oz;
option: approx 1 oz (added to tach weight)

Incremental Encoder Dimensions (in inches)

Standard Output

Face-mount (SA)

Flange-mount (SB)

Amplified Output

Face-mount (SA)

Flange-mount (SB)

Encoder-Option Dimensions (without amplifier)

Output Diagram