Redundancy
Redundancy is the provision of additional equipment, components, or paths so a required function can continue when one element fails.
What this term means in maintenance
Redundancy is the provision of additional equipment, components, or paths so a required function can continue when one element fails.
Types of redundancy
Common arrangements include:
- Duty and standby
- Two-out-of-three voting
- Parallel pumps
- Dual power supply
- Alternate communication path
- Spare production capacity
Practical example
Two pumps are installed so either one can meet full process demand. One operates while the other remains available as standby.
Redundancy must be effective
Redundant equipment should avoid shared vulnerabilities such as:
- Same power source
- Same control panel
- Same suction blockage
- Same environmental exposure
- Common maintenance error
- Common software fault
Maintenance requirements
Standby equipment may require:
- Routine testing
- Rotation
- Failure-finding tasks
- Condition monitoring
- Battery or fuel checks
- Automatic-transfer testing
Common mistake
Assuming installed standby equipment is available without proof testing can hide failed redundancy.
How this term differs
Redundancy is the provision of additional capacity or components to preserve function after failure. It is related to Single Point of Failure, Common Cause Failure, and Common Mode Failure, but these terms describe different records, measures, roles, strategies, or decisions and should not be used interchangeably.
Related concepts
Related maintenance terms
Keep exploring connected CMMS, reliability, and maintenance planning terms.
Single Point of Failure
A single point of failure is one component, asset, or function whose failure can stop the entire required system because no effective alternative exists.
Hidden Failure
A hidden failure is a loss of function that is not evident during normal operation and may remain undetected until another event creates demand.
Equipment Availability
Equipment availability is the percentage of required or scheduled time during which an asset is capable of performing its intended function.
Glossary FAQs
- What is redundancy?
Additional equipment or paths that preserve a required function after one element fails.
- What is duty-standby redundancy?
One unit operates while another remains available to take over.
- Why must standby equipment be tested?
An untested standby can contain a hidden failure and provide no real protection.