The Value of Condition-Based Monitoring. Part I: Preparation


Diligent monitoring of the condition of equipment at manufacturing plants (condition-based monitoring) can have a big impact on the company. This is an increasingly urgent issue in a market where approximately $65 billion worth of automation systems are at or near the end of their useful life. The oldest equipment still in use dates back to 1938.

Condition-based monitoring can greatly reduce the cost of repairs and keep the company assets up and running for longer periods. At the same time, it allows the company to reduce costs and generate more revenue.

You’ll find below the way to begin condition-based monitoring in your operation. Keep in mind that the work outlined below should be performed within the context of a business case to ensure the work is has a good ROI, is based on an incremental process of Proof of Concept through Production, and that it is performed in a culture that drives and welcomes change for the betterment of the company and all who work there.


To monitor equipment, there are three prerequisites you need to ensure that you can prevent major issues and realize the resulting cost saving and additional revenue. They are:

  • Know the equipment
  • Know the Issues
  • Have a tool

Know the Equipment

Before you start hooking up sensors and software to equipment you need to know your equipment:  how it needs to operate for optimal outcomes, its suggested limits, and how it can fail. The team working to set up condition-based monitoring must understand the technology and the operations of the equipment so they know what is normal and what is abnormal. They can then translate this information to the monitoring system.

You’ll want to record this information for both the primary function of the equipment (its main purpose) such as a high-pressure air compressor that supplies compressed air) and also the functions of its components (e.g., electric motors, pumps, valves, etc.). If possible, this information should be organized into a hierarchical diagram, with primary functions at the top and lower level support functions further down the diagram.  It is important to document the individual component functions because those functions and breakdowns ( loss of function) can negatively impact the whole piece of equipment and ultimately, the performance of the plant.

Next, you must define and agree upon the operating context of the equipment. The operating context means the desired operating parameters of the equipment. For example, what are the capabilities of the equipment and its components, what are the optimal minimum and maximum operating parameters for the equipment (e.g., power, flow, pressure), and suggested shutdowns and maintenance work. You can usually find all this information in operating and maintenance manuals.

Know the Issues

Once you have defined normal operating conditions, you are ready to define the failures or potential failures What are the different ways that a component could fail? What is the potential impact on the equipment and other components if the component in question fails? How can that failure be identified in terms of operating parameters (e.g., pressure rises above 100 psi) or other data (e.g., the temperature of the motor casing rises above 200 degrees). These definitions are referred to as failure modes. Along with defining the failure modes, the team should define proactive tasks that can be performed to mitigate or eliminate the issues.

Next time, we’ll discuss the keys to successfully implementing a condition-based monitoring system.