Electrical distribution and transmission equipment is generally designed for a certain economic service life. Equipment life is dependent on operating environment, service performance requirements, maintenance program effectiveness and the quality of the original manufacture and installation. Beyond this estimated service life period equipment is not expected to provide operational reliability. The majority of equipment is found to operate satisfactorily even after the anticipated life span which may be attributed to built in overdesign or any one of many dependent contributors.
Generally due to variable factors such as substandard materials and manufacturing techniques, frequent system faults, over loading or overvoltage stress and environmental effects during normal operation, some equipment does fail much earlier than expected life span. Due to the above cited reasons, the failure of vital equipment has become a more regular occurrence and the high rate of failure has become a serious issue for electrical utilities and large industry. The concept of simple replacement of power equipment before or after reasonable economic service life, considering it as weak or estimated source of trouble, is no longer supportable in the present scenario of financial constraint.
Today the paradigm has changed and efforts are being directed to explore new approaches and technologies for monitoring, diagnosis, life assessment and condition evaluation of key and essential electrical equipment. With this the possibility of extending existing asset service life while not compromising reliability is afforded. A simple analogy is that of driving a vehicle for 300,000 KM vs 150,000 KM through diligent monitoring, maintenance and repairs as necessary. Maximizing the service life of the electrical power system assets, balanced with cost of operation, is a prerequisite for best in class electrical engineering. For electrical utilities and industries this ensures reliability and safety in power supply at optimum cost over the life of the installation.
The main goal is therefore to reach a cost effective solution using available resources which is captured by the concept of Asset Management. Maintenance is one of the areas where higher effectiveness is sought and so organizations are researching and implementing new strategies. The pressure to reduce maintenance costs as well as outage time for this work is already being realized and the concept of Preventive Maintenance is undergoing scrutiny and change. Much, fairly ineffective to date, research has been undertaken to take "rule of thumb" life expectancy analysis to the next level.
In practice, one traditional understanding of reactive maintenance is to "fix it when it breaks". This is a good definition for repair, but not maintenance. In sophistacated and forward thinking utilities and industries, it has been realized that proactive, rather than reactive maintenance management brings far superior results. Adopting a proactive approach to maintenance will improve maintenance effectiveness dramatically within the confines of an organizational cultural where an existing, predominantly reactive maintenance program exists.
Most equipment requires regular and effective maintenance to operate correctly and meet their design specifications. The consequences of ineffective equipment maintenance can be huge in terms of system reliability indices, revenue loss and corporate image. The importance of effective maintenance through electrical system and equipment condition monitoring is gaining importance to reduce the occurrence of such incidents. Assessing the condition and thereby reducing equipment failure is a key to improving reliability and also effectively extending the life of equipment. Hence utilities are continuously in search of best maintenance practices other than traditional methods/techniques to assess the condition of equipment in service so that remedial measures can be taken proactivly to avoid disastrous in service failure and of course saving valuable resources.
The potential cost savings of Condition Based Maintenance Practices can sometimes go beyond the immediate understanding of ownership and management. Benchmarking standards are real, specific, achievable and proven standards for maintenance management. By adopting these any maintenance department will become more efficient by way of reducing operating and maintenance costs, improving reliability, and increasing overall efficiencies. Condition Based Maintenance Practices comprise of standards and methods. Standards are the measurable performance levels of maintenance execution and methods and strategies are procedures that must be practiced in order to meet the standards. The effort towards development of a Manual will help organizations to define the standards and show them how to set targets and reach the new performance levels of Condition Based Maintenance Practices. It will also provide them with detailed study on failure modes, criticality assessment, strategies and actions to be taken, maintenance procedures and analyses needed to execute Condition Based Maintenance Practices. A CMMS is critical to an organized, efficient transition to a proactive maintenance approach. The types of reports and data tracking that can be obtained from CMMS include "just in time" prioritized work orders and electrical system performance and reliability. Customizations of reports to client specific requirements are possible within system capabilities. A final item to consider when incorporating Condition Based Maintenance Practices is integrating the use of contractor information into the maintenance data base of the organization. This requires all parties to follow the same format of information/data collection and entry into the CMMS.
The transition from a reactive maintenance organization methodology to a proactive program is not a simplistic undertaking. It will take time, effort, planning and "top to bottom" engagement to accomplish. The transition requires commitment from all levels of the organization.
15 Sherwood Heath NW,
Calgary, Alberta, T3R 1P4, Canada.
