Certified Automation Professionals (CAPs) are responsible for the direction, design, and deployment of systems and equipment for manufacturing and control systems.
How are the maintainability and maintenance of automation systems related?
A. Maintainability is a front-end, design outcome; maintenance is related to ongoing system availability.
B. Maintainability is related to system availability; maintenance is related to traceability and warranties.
C. Maintainability is a front-end engineering function; maintenance is an ongoing engineering function.
D. Maintainability is related to malfunctions; maintenance is related to service quality.
The correct answer is A, "Maintainability is a front-end, design outcome; maintenance is related to ongoing system availability."
Maintainability is the probability that a device will be restored to an operating condition within a specified period when maintenance is done with prescribed resources and procedures. It can also refer to the inherent characteristic of a design or installation that determines the ease, economy, safety, and accuracy with which maintenance actions can be performed on it.
As such, maintainability should be addressed during the front-end engineering and design phase of a project, so these characteristics are built in to the process. This includes addressing items like accessibility for removing pumps, piping, and instruments; complete documentation and procedures; availability of spare parts; personnel training and qualification; and suitability for purpose.
Maintenance is what is performed on a system to ensure that it remains in good working condition, but also, if a failure should occur, maintenance is the mechanism used to return the system to the previous working condition.
Reference: Trevathan, Vernon L., A Guide to the Automation Body of Knowledge, Second Edition, ISA, 2006.
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