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RR28 Reflective Optical Encoder Module | Miniature 3-Ch 500~16000 CPR | EPOCH| Miniature 3-Ch 500~16000 CPR | EPOCH

[RR28 SERIES] standard miniature reflective optical encoder module

RR28 Reflective Optical Encoder Module — Miniature Design, 3-Channel 500~16000 CPR Differential Output, for DC Motor & Servo Motor Feedback

Name: RR28 Reflective Optical Encoder Module
Brand: EPOCH
Availability: InStock

The EPOCH RR28 Series is a miniature reflective optical encoder module with PCBA and integrated housing design, with code disc. Outputs three channels of differential signals ranging from 500~16000 CPR. The Z (index) signal can be selected from 90°, 180° and 360° (standard: 90°). The RR282 sub-series outputs two channels of 1000-count differential signals. Suitable for small size DC motor, stepping motor, and servo motor.

Quick Select: Mechanical Dimensions Features Tech Specs Waveform Pin Definition Ordering Guide FAQ

RR28 Mechanical Dimension Drawings — Miniature Reflective Optical Encoder Module Footprint (Ø28 x 18 mm)

RR28 Mechanical Dimension Drawing

RR28 Reflective Optical Encoder Module Mechanical Dimension Drawing

Miniature form factor designed for small-size DC motor integration. Unit: mm.

RR28 Reflective Optical Encoder Module — Dimensions of Motor End Face and Outgoing Shaft Length

RR28 Reflective Optical Encoder Module Motor End Face Dimension Drawing

Motor shaft axial play ≤ 0.1 mm

RR28 Series Reflective Optical Encoder Module — Description & Key Features

•

Type: Miniature reflective optical encoder module with PCBA & integrated housing

•

Resolution: 500 ~ 16,000 CPR (3-channel differential)

•

Output: 3-Channel (A, A/, B, B/, Z, Z/) — Differential type

•

Z Signal Options: Selectable 90°, 180°, or 360° (standard 90°)

•

Supply: 3V ~ 5V DC

•

Max Speed: 11,000 RPM

•

Temp Range: -40°C to +85°C

•

Design: With code disc, PCBA integrated housing

•

Connector: GH1.25-1x10P (10-pin)

•

Sub-model RR282: 2-channel differential, 1000-count output

Applications: This RR28 reflective optical encoder module is suitable for small size DC motor, stepping motor and servo motor. Part of EPOCH's Optical Encoder Modules series designed for compact motor feedback applications requiring high resolution up to 16,000 CPR.

RR28 Series Technical Specifications — 3-Channel Differential Output, 500~16000 CPR

Parameter	RR28	RR282
Resolution (CPR)	500 ~ 16,000	1,000 (Fixed)
Output Channels	3-Channel: A, A/, B, B/, Z, Z/	2-Channel: A, A/, B, B/
Output Type	Differential (RS422)
Supply Voltage	3 ~ 5V DC
Maximum Speed	11,000 RPM	11,000 RPM
Operating Temperature	-40°C ~ +85°C	-40°C ~ +85°C
Z Signal Options	90°, 180°, 360° (Standard: 90°)	N/A
Connector	GH1.25-1x10P
Motor Shaft Axial Play	≤ 0.1 mm

RR28 Output Waveform Diagram — 3-Channel Differential Timing (Clockwise Rotation)

RR28 Reflective Optical Encoder Module Waveform Diagram — 3-Channel Differential Output Clockwise Rotation

Waveform during clockwise (CW) rotation. Three-channel differential output (A, A/, B, B/, Z, Z/). Channel A leads Channel B for clockwise rotation. Z (index) pulse width selectable: 90°, 180°, or 360° electrical degrees (standard: 90°).

RR28 Pin Definition — 10-Pin GH1.25-1x10P Connector

Connector model: GH1.25-1x10P. Pin assignment for RR28 3-channel and RR282 2-channel configurations.

Pin No.	Signal (RR28)	Signal (RR282)	Direction	Description
1	VCC	VCC	Input	Power Supply 3~5V DC
2	GND	GND	Input	Ground (0V)
3	A	A	Output	Channel A (+) Differential Output
4	A/	A/	Output	Channel A (-) Differential Output
5	B	B	Output	Channel B (+) Differential Output
6	B/	B/	Output	Channel B (-) Differential Output
7	Z	N/C	Output	Index Z (+) Differential Output (RR28 only)
8	Z/	N/C	Output	Index Z (-) Differential Output (RR28 only)
9	N/C	N/C	—	Not Connected (Reserved)
10	N/C	N/C	—	Not Connected (Reserved)

RR28 Ordering Information / Part Number Code — Reflective Optical Encoder Module

Code Structure: RR28 [CPR Code] [Shaft Code] [Year Code] — example: RR28-A-01-24

R

→

R

→

2

→

8

→

-

→

CPR Code

→

-

→

Shaft Code

→

-

→

Year Code

Series Prefix

Dash

e.g. A=500, B=1000

Dash

e.g. 01=2mm, 11=4mm

Dash

e.g. 24=2024

CPR Code	A	B	T	N	8K	16K
CPR	500	1,000	2,000	4,000	8,000	16,000

Shaft Code	01	02	03	04	05	06	11
RR28	2 mm	3 mm	1/8 in	5/32 in	3/16 in	1/4 in	4 mm
RR282	Code 14 — 5 mm only

Housing Type	1	2
RR28 / RR282	Perforated housing	Non-perforated housing

RR282 Sub-Model (2-Channel): Add suffix "2" to the series code — RR282 [CPR Code] [Shaft Code] [Year Code]. CPR codes: A (500), B (1,000). Shaft code: 14 (5 mm). No Z signal output.

Z Signal (RR28 3-Channel only): Configurable to 90°, 180°, or 360° electrical degrees. Standard default: 90°. Must be specified when ordering.

RR28 Reflective Optical Encoder Module Printing — Model Print Label

RR28 Reflective Optical Encoder Module Model Print Label

Technical FAQs — RR28 Series Reflective Optical Encoder Module

Q: What resolution options are available for the RR28 reflective optical encoder module?

A: The RR28 reflective optical encoder module offers resolutions from 500 CPR to 16,000 CPR with 3-channel differential output. The RR282 sub-model offers a fixed 1,000 CPR with 2-channel differential output. Contact EPOCH for specific CPR code availability.

Q: What is the difference between the RR28 and the RR282 reflective encoder module?

A: The RR28 is a 3-channel model (A, A/, B, B/, Z, Z/) with selectable resolution from 500~16,000 CPR and an adjustable Z (index) signal. The RR282 is a 2-channel model (A, A/, B, B/) with a fixed 1,000 CPR output and no Z signal. Both share the same PCBA and integrated housing design and the same GH1.25-1x10P connector.

Q: How does the Z (index) signal selection work on the RR28 3-channel differential encoder?

A: The Z signal on the RR28 3-channel differential encoder can be configured to 90°, 180°, or 360° electrical degrees. Unless otherwise specified, the standard product ships with 90° Z signal. This allows flexibility for different position reference requirements in servo motor and stepping motor applications.

Q: What is the difference between an encoder module and a traditional rotary encoder?

A: An encoder module (like the RR28) features a PCBA and integrated housing design with a code disc, but has no bearing or shaft of its own. It is designed to be mounted directly onto a motor, using the motor's own shaft and bearings. This makes it more compact and cost-effective for integration into DC motors, stepping motors, and servo motors. A traditional rotary encoder is a self-contained unit with its own bearings and shaft.

[CROSS-REFERENCE] Related Products

Also available: RT28 Series Reflective Optical Encoder Module — 28mm form factor, 2-channel 100~1000 CPR for standard motor feedback applications.

B2B Global RR28 Encoder Module Sourcing

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Need custom resolution, Z signal configuration, or bulk pricing? Contact our sales team.

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Sales: liya@epoch-electronic.com

Legal Disclaimer: All manufacturer names and trademarks referenced are for cross-compatibility reference only. EPOCH is an independent manufacturer with no affiliation to OEM brands.