Are you thinking which encoders will be the best for your system? Absolute encoders or incremental rotary encoders? Both of these encoders have their own pros and cons. Having a look at their advantages as well as disadvantages along with their applications will help you choose the best option for your system.
Before we start with the pros and cons of absolute and rotary encoders, let us have a brief discussion on both of these types of encoders:
Absolute Encoders
An absolute encoder gives a digital position value for every spot the shaft can be in. Even if the power goes out it will still know where the shaft is when the power comes on. It does not need to go to a reference point to figure this out.
Advantages of Absolute Encoders
- It remembers where the shaft was even after the power is turned off
- You do not need to calibrate it when you start it up
- It is very good at figuring out the position
- It is perfect for things that need to be safe and precise
- You can get it in turn and multi-turn versions
Typical Applications
- Industrial robots
- CNC machines
- equipment
- Automated guided vehicles
- Elevators and cranes
- Servo motor positioning systems
Incremental Encoders
An incremental encoder makes pulses when the shaft turns. The control system counts these pulses to figure out how far something has moved and how fast it is going. It is different from an encoder because it does not know where it is if the power goes out.
Advantages of Incremental Encoders
- These encoders are affordable and easy to install and set up.
- These are great for watching speed and direction
- You can get these with a lot of pulse resolution options
- These work well for a lot of automation tasks
These encoders, however, also come with some limitations
- You have to do a homing sequence when you turn it on
- It forgets where it was if the power goes out
- If it misses some pulses, it can make counting mistakes
