When it comes to reliability and operational warranty of your electric machines, maintenance is an indispensable item. There are basically three types or intervention policies that are best known in maintenance: corrective, preventive, and predictive. But what is the difference between them and which is the best choice? It is normal to have doubts when talking about asset maintenance, so the idea of this article is to clarify the differences between maintenance and its benefits.


What is corrective maintenance?

Still very present in companies, corrective maintenance is only used when some equipment breaks down or fails. This method does not use maintenance planning, which leads to the need for parts inventory and availability of professionals, since the failures are not foreseen and cause the idleness of machines and labor.

For example, a machine seems to be in perfect condition and in constant production, but at some point a part presented a failure and the production had to be stopped. Since there was no planning, the maintenance professional, before correcting it, needs to understand the problem, check if the part can be replaced and if there is in stock. This situation will cause the company to make the machine unavailable, which will generate costs per machine stopped, part that needs to be replaced, and labor costs.

When performed without planning, corrective maintenance generates huge inconveniences, compromising the fulfillment of deadlines and especially operational profitability.

What is preventive maintenance?

When we talk about maintenance planning, one of the best paths to follow is certainly the preventive maintenance. It is the maintenance that corrects problems and failures even before they happen, thus reducing costs, machine unavailability, and increasing maintenance efficiency. Its main characteristic is the possibility of scheduling maintenance, avoiding problems with parts inventory, idle machines, and lack of production.

The tip we leave in this maintenance is to focus on the expected result, to evaluate the condition and operational reliability of the equipment, and not to focus only on the execution of the tasks pre-established by the planning. In an electrical machine, the electrical and mechanical tests and visual inspection are conditions to analyze its results and from there make a critical analysis and conclude potential problems and the degree of reliability that it is, that is, for this the presence of an electrical machine specialist is essential.

In the market we also commonly hear the term “rejuvenation” for preventive maintenance, which can lead to a misinterpretation. There is no way to rejuvenate what is already aging. We can prevent accelerated aging.

What is predictive maintenance?

It is safe to say that predictive maintenance is a step ahead of preventive maintenance. It is the most accurate follow-up and planning maintenance, requires greater qualification of the professional and aims to prevent any failure of parts before they even present a defect. It is characterized by monitoring equipment parameters, such as partial discharges, vibration, temperature, etc.

Predictive maintenance uses the monitoring of the parameters of the parts so that their replacement can be done before the end of their useful life. By inspecting the machine, the maintenance professional – based on the monitoring parameters – identifies the need to change components and schedules the best moment for maintenance, which is done without intervention in production, facilitating maintenance and avoiding higher costs with machine idleness.

What company wants to stop its production because of a failure or defect? Very similar to preventive maintenance, predictive maintenance has as a positive point the possibility of programming its actions. Planning and follow-up of the parts are important factors, which working together, reduce costs with losses and increase the effectiveness in the production of the machines.


NISHI offers solutions for all types of maintenance. Contact us and request an evaluation of reliability and operational warranty of your electric machine.