# What is the difference between Rockwell ControlLogix and CompactLogix?

**URL:** <https://forumautomation.com/t/what-is-the-difference-between-rockwell-controllogix-and-compactlogix/11899>\
**Category:** Allen Bradly\
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**Created:** [March 23, 2024, 9:45am UTC](https://forumautomation.com/t/what-is-the-difference-between-rockwell-controllogix-and-compactlogix/11899 "2024-03-23T09:45:36Z")\
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**Author:** ![Instrument\_Engineer](https://forumautomation.com/user_avatar/forumautomation.com/instrument_engineer/32/6734_2.png) [@Instrument\_Engineer](https://forumautomation.com/u/Instrument_Engineer)\
**Post date:** [March 23, 2024, 9:45am UTC](https://forumautomation.com/t/what-is-the-difference-between-rockwell-controllogix-and-compactlogix/11899/1 "2024-03-23T09:45:36Z")

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## What is the difference between Rockwell ControlLogix and CompactLogix?

 ![image](https://cdn.forumautomation.com/original/2X/4/4995dba4e354243f8e023ba05d2f6d758ee03b90.jpeg)

Rockwell Automation offers two main families of programmable logic controllers (PLCs): ControlLogix and CompactLogix. While both families are part of Rockwell’s Logix platform and share some similarities, there are several key differences between them:

## Size and Form Factor:

### ControlLogix:

- ControlLogix PLCs are typically larger and modular, consisting of a chassis or rack that can accommodate multiple modules such as processors, I/O modules, communication modules, and power supplies.
- These PLCs are suitable for large-scale applications with extensive I/O requirements.

### CompactLogix:

- CompactLogix PLCs are smaller and more compact, often designed as a single integrated unit or in a smaller rack format.
- They are ideal for applications with space constraints or smaller-scale automation projects.

## Scalability:

### ControlLogix:

- ControlLogix PLCs offer higher scalability and expandability due to their modular design.
- Users can easily add or remove modules to meet changing application requirements, making them suitable for large and complex automation systems.

### CompactLogix:

- CompactLogix PLCs are less scalable compared to ControlLogix PLCs.
- While they still offer some level of modularity, their compact design limits the number of available slots for expansion modules, making them more suitable for smaller to mid-sized applications.

## Performance and Processing Power:

### ControlLogix:

- ControlLogix PLCs typically feature more powerful processors and higher performance capabilities compared to CompactLogix PLCs.
- They can handle larger amounts of data, complex logic, and faster processing speeds, making them suitable for demanding applications that require high-speed control and extensive data processing.

### CompactLogix:

- CompactLogix PLCs offer sufficient processing power for many automation applications, but they may have limitations in terms of processing speed and capacity compared to ControlLogix PLCs.
- They are well-suited for smaller-scale applications with less demanding control requirements.

## I/O Density:

### ControlLogix:

- ControlLogix PLCs often support higher I/O density, allowing them to accommodate a larger number of I/O modules and channels within a single chassis or rack.
- This makes them suitable for applications with extensive I/O requirements.

### CompactLogix:

- CompactLogix PLCs typically have lower I/O density compared to ControlLogix PLCs.
- While they still support a wide range of I/O modules, their smaller form factor limits the total number of I/O channels that can be integrated into a single unit.

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**Author:** ![automation\_engineer6](https://forumautomation.com/user_avatar/forumautomation.com/automation_engineer6/32/7656_2.png) [@automation\_engineer6](https://forumautomation.com/u/automation_engineer6)\
**Post date:** [September 6, 2024, 2:58pm UTC](https://forumautomation.com/t/what-is-the-difference-between-rockwell-controllogix-and-compactlogix/11899/2 "2024-09-06T14:58:20Z")

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**Additional Differences Between ControlLogix and CompactLogix:**

1. **Redundancy Capabilities:**

- **ControlLogix** : Supports redundancy for critical applications where system uptime is essential. You can set up redundant controllers and network paths.
- **CompactLogix** : Generally does not support redundancy, making it less suitable for applications that require high availability.

1. **Communication Options:**

- **ControlLogix** : Offers more flexible and extensive communication options, including multiple network modules for Ethernet/IP, ControlNet, DeviceNet, and more.
- **CompactLogix** : Supports Ethernet/IP and some other networks but with fewer options compared to ControlLogix.

1. **Integration with Safety Systems:**

- **ControlLogix** : Can integrate more seamlessly with Rockwell’s safety controllers and safety I/O, providing a comprehensive solution for safety-critical applications.
- **CompactLogix** : Also integrates with safety components but is more limited in options and scale.

1. **Application Type:**

- **ControlLogix** : Often used in large, complex systems like process control, batch control, or large-scale machinery automation.
- **CompactLogix** : More suited for smaller systems like machine-level control, packaging, or OEM applications.

1. **Cost Considerations:**

- **ControlLogix** : Generally higher in cost due to its modularity, scalability, and higher performance.
- **CompactLogix** : More cost-effective for smaller applications with fewer requirements.