How do I determine the right Pulses Per Revolution (PPR) for my rotary encoder?

The required PPR depends on the precision your application needs. Lower PPR values (e.g., 100-400) are suitable for manual control inputs or simple speed monitoring. Higher PPR values (1000 and above) are necessary for high-accuracy positioning, motor feedback, and high-speed applications. Always match the PPR to your controller's input capabilities.

What is the difference between NPN and PNP output types?

NPN encoders provide a sinking output that switches the signal to ground (0V), while PNP encoders provide a sourcing output that switches the signal to your positive supply voltage. You must choose the type that matches the input circuit of your PLC or controller. Check your controller's documentation, as using the wrong type will prevent the signal from being read.

What is an AB 2-phase output used for?

An AB 2-phase output provides two square wave signals that are 90 degrees out of phase. This allows the connected control system to determine not only the amount of rotation but also its direction. Many of our encoders feature this output for complete motion tracking.

Does the operating voltage for an encoder need to be exact?

No, most industrial encoders operate across a voltage range, such as 5-24V DC or 8-24V DC. As long as your system's supply voltage falls within this specified range, the encoder will function correctly. Always verify the acceptable voltage range on the product datasheet to prevent damage.

When should I choose a stainless steel encoder versus an alloy one?

Choose a stainless steel body for encoders used in harsh industrial environments with exposure to moisture, chemicals, or frequent washdowns, as it offers superior corrosion resistance. For general-purpose machinery in controlled environments, an alloy body provides sufficient durability and strength.

Encoders

23 products available

A rotary encoder is a sensor that converts the angular position or motion of a shaft into an analog or digital signal. These devices are fundamental to industrial automation, providing precise feedback for motor control, robotics, PLC systems, and machinery positioning. Compel is a leading UK supplier of industrial encoders for trade professionals and engineers.

Our range includes many encoder types, with a focus on incremental optical and photoelectric models. We stock components with a wide variety of specifications, including different pulses per revolution (PPR) from 50 to over 1000, common operating voltages like 5-24V DC, and both NPN and PNP output types. Find the exact rotary encoder for your system's mechanical and electrical requirements.

23 products in Encoders

Five EC11 rotary encoder code switches with push buttons, 30 positions, 360-degree rotation, SMD 5-pin plum shaft.

Encoders

Rotary Encoder | 30 Position with Push Button | SMD 5-Pin Plum Shaft

TBS-06251ENCO-00014

£4.99

Encoders

Rotary Encoder | 5-Pin with Push Switch | 10mm Plum Shaft EC11

TBS-06280ENCO-00019

£4.99

A pair of EC12 360-degree rotary encoder with button switch, featuring 24 positioning and 24 pulse.

Encoders

Encoder with Push Button | 24-Pulse for Audio Mixers | 18mm Half Shaft

TBS-06490ENCO-00022

£6.99

Five EC11 rotary encoder with push switch, 5-pin, 20mm shaft, suitable for digital potentiometer DIY kits.

Encoders

Encoder with Switch | 20mm Shaft for DIY Kits | 5-Pin EC11 Digital

TBS-06279ENCO-00018

£7.99

E6B2-CWZ6C incremental photoelectric rotary encoder, a precise pulse meter for motors.

Encoders

Rotary Encoder | 600 P/R Resolution | 5-24VDC Pulse Output

TBS-06259ENCO-00016

£62.99

A lot of five EC11 rotary encoder units, featuring half or plum blossom shafts and 15mm/20mm handles.

Encoders

Rotary Encoder | 5-Pin with Push Button | 15mm/20mm Half-Moon Shaft

TBS-06226ENCO-00013

£4.99

E38 incremental optical rotary encoder with 6mm shaft, offering various pulse per revolution options.

Encoders

Rotary Encoder | 6mm Shaft AB Two Phase | 5-24VDC 1000 P/R

TBS-06278ENCO-00017

£26.99

A 38S6G5-Z rotary encoder, incremental type, with various pulse options (50-2000P/R) and NPN output.

Encoders

Rotary Encoder | 1000 PPR Resolution | NPN A/B/Z Phase Output

TBS-06479ENCO-00021

£28.99

A robust DC 5-24V 360/600 P/R photoelectric incremental rotary encoder with a 6mm shaft for game steering wheels.

Encoders

Rotary Encoder | 600 P/R Incremental | 6mm Shaft for Gaming

TBS-06203ENCO-00011

£12.99

A photoelectric incremental rotary encoder 38S6G5-B-G24N, featuring a robust metal casing.

Encoders

Rotary Encoder | 600 PPR AB Phase | 8-24V NPN Optical Sensor

TBS-06257ENCO-00015

£28.99

A set of five 20-position incremental 360 rotary encoder knobs with push buttons, EC11 type.

Encoders

Encoder with Knob | 20 Position Incremental | EC11 for Arduino

TBS-06202ENCO-00010

£4.99

Five half/plum axis rotary encoder units, with handle lengths of 15mm or 20mm, functioning as digital potentiometers.

Encoders

Encoder with Switch | 15mm & 20mm Plum Shaft | EC11 Digital Pot

TBS-06214ENCO-00012

£10.99

An OVW2-06-2MHT-10-2MD-1024-01 incremental optical rotary encoder with DC 5-24V input.

Encoders

Rotary Encoder | 1024 PPR Optical | DC 5-24V Automation

TBS-06102ENCO-00008

£63.99

OMCH GNS38B Magnetic Incremental Rotary Encoder, a precise rotary encoder for position sensing.

Encoders

Rotary Encoder | 6mm Shaft Diameter | 600 P/R AB 2-Phase NPN

TBS-06143ENCO-00009

£34.99

An E6B2CWZ6C optical rotary encoder, also known as E6B2-CWZ6C, offering various pulse options including 2500, 2000, 1024, 1000, and more.

Encoders

Rotary Encoder | E6B2-CWZ6C | 1000 PPR 2000 PPR Incremental

TBS-06089ENCO-00005

£66.99

Encoders

Rotary Encoder | Photoelectric Pulse Meter | For Motor Speed Control

TBS-06086ENCO-00004

£60.99

A silver photoelectric incremental rotary encoder with a black cable and a metal shaft, designed for precise position sensing.

Encoders

Rotary Encoder | Optical AB 2-Phase Sensor | NPN Collector Output

TBS-06100ENCO-00007

£26.99

Cloweit 38mm incremental rotary encoder with 6mm shaft, A/B/Z-2/3 phases, and 10-3600 PPR for precise motion sensing.

Encoders

Rotary Encoder | 38mm Body 6mm Shaft | 1024 PPR 5-24VDC

TBS-06084ENCO-00003

£41.99

Incremental optical rotary encoder with a 6mm shaft, offering 100 to 1024 P/R resolution for precise motion sensing.

Encoders

Rotary Encoder | 1024 P/R AB 2-Phase | 5-24V 6mm Shaft

TBS-06068ENCO-00002

£18.99

Optical rotary encoder E6B2 CWZ6C, a high-precision photoelectric incremental sensor for motion control.

Encoders

Rotary Encoder | E6B2 Incremental Optical | 1024 P/R 5-24V DC

TBS-06096ENCO-00006

£36.99

Encoders

Rotary Encoder | 20 Position with Push Button | 15mm Shaft (10-Pack)

TBS-06492ENCO-00023

£9.99

A 38S6G5-B-G24N photoelectric incremental rotary encoder with AB 2 phase and NPN PNP output.

Encoders

Rotary Encoder | NPN & PNP Output | 360 PPR for Motor Control

TBS-06472ENCO-00020

£14.99

A 38S6G5-B-G24N photoelectric incremental rotary encoder with 50-600PPR and NPN output.

Encoders

Rotary Encoder | AB 2-Phase Optical | 600 PPR for PLC Systems

TBS-06063ENCO-00001

£19.99

Selecting the Correct Encoder Type and Resolution (PPR)

The first step is to identify the correct encoder type for your task. Most industrial applications use incremental rotary encoders, which generate a pulse for each fractional rotation of the shaft. This data is used to determine speed, distance, and position. The primary technology is optical (or photoelectric), which offers high reliability and precision.

Resolution, measured in Pulses Per Revolution (PPR), defines the encoder's precision. A higher PPR means more pulses for a single 360° rotation, allowing for finer position and speed control. Our selection covers a broad spectrum, from low-resolution models (50-400 PPR) suitable for manual inputs and basic speed feedback, to high-resolution units (600, 1024, or more) required for precise motor control and CNC machinery.

Matching Electrical Specifications to Your System

An encoder must be electronically compatible with your control system (e.g., a PLC, VFD, or microcontroller). First, verify the operating voltage. Most of our encoders operate on a flexible DC voltage range, typically 5-24V or 8-24V, which accommodates common industrial power supplies.

Next, confirm the output type. NPN (sinking) and PNP (sourcing) are the two main standards for 3-wire DC sensors. Your choice depends entirely on the input requirements of your controller. We stock encoders with NPN, PNP, and NPN open collector outputs. Also, check the output phase. An AB 2-phase output is standard for determining direction, while an additional Z phase provides a once-per-revolution index pulse for homing.

Ensuring Mechanical Fit and Durability

Correct mechanical integration is used for reliable operation. Key dimensions to check include the shaft diameter (e.g., 6mm), shaft length (e.g., 15mm or 20mm), and the overall body diameter of the encoder. Our product listings provide detailed specifications for shaft types, such as plum or half shaft, to ensure a secure fit with your coupling or knob.

The encoder's housing material affects its durability and suitability for the operating environment. We offer encoders with bodies made from materials like stainless steel, alloy, and ABS. Stainless steel provides excellent corrosion resistance for washdown areas, while alloy offers a good balance of strength and weight for general machine applications.

Buying guide

Choosing Encoders

How do I determine the right Pulses Per Revolution (PPR) for my rotary encoder?: The required PPR depends on the precision your application needs. Lower PPR values (e.g., 100-400) are suitable for manual control inputs or simple speed monitoring. Higher PPR values (1000 and above) are necessary for high-accuracy positioning, motor feedback, and high-speed applications. Always match the PPR to your controller's input capabilities.
What is the difference between NPN and PNP output types?: NPN encoders provide a sinking output that switches the signal to ground (0V), while PNP encoders provide a sourcing output that switches the signal to your positive supply voltage. You must choose the type that matches the input circuit of your PLC or controller. Check your controller's documentation, as using the wrong type will prevent the signal from being read.
What is an AB 2-phase output used for?: An AB 2-phase output provides two square wave signals that are 90 degrees out of phase. This allows the connected control system to determine not only the amount of rotation but also its direction. Many of our encoders feature this output for complete motion tracking.
Does the operating voltage for an encoder need to be exact?: No, most industrial encoders operate across a voltage range, such as 5-24V DC or 8-24V DC. As long as your system's supply voltage falls within this specified range, the encoder will function correctly. Always verify the acceptable voltage range on the product datasheet to prevent damage.
When should I choose a stainless steel encoder versus an alloy one?: Choose a stainless steel body for encoders used in harsh industrial environments with exposure to moisture, chemicals, or frequent washdowns, as it offers superior corrosion resistance. For general-purpose machinery in controlled environments, an alloy body provides sufficient durability and strength.