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As an initial step to implement total quality management (TQM) in a small manufacturing enterprise (SME) of electrical products, we applied statistical techniques to quantify and evaluate the data collected in order to improve the quality characteristics of a selected product circuit breaker. A circuit breaker will “jump” or the current will be cut short if a current stronger than 15A passes through the equipment. The time required for the circuit breaker to stop the flow of the current is called the trip‐time. Our major concern is to find out how sensitive a 15A circuit breaker is, and how reliable is the device. We were able to confirm several dominant factors that influence the trip‐time of the circuit breaker after conducting several experiments. We used regression analysis to find out the model that best fits the relationship between the current supply and the trip‐time of the 15A circuit breaker. Meanwhile reliability testings of the circuit breaker were performed. Balanced factorial design techniques were applied in finding out the optimal combination of factors with the highest success rate of trips. The results demonstrated that the optimal combination of factors we found could bring about quality improvement of the product.

The purpose of this paper is to review cotemporary maintenance programs and analyze factory production data for an SF₆ gas filled circuit breaker population. Various maintenance techniques and studies are reviewed to understand the reliability of circuit breaker models and the impact manufacturing can have on long term maintenance considerations.

Production and field event data were analyzed using statistical analysis tools. The population data were formatted so that a recurrent event analysis could be conducted to establish the mean cumulative function (MCF) by model and product family (class). Average Field Two‐year Recorded Event Rate (AFTRER) is introduced and compared to commonly used Field Incident Rate (FIR) and Mean‐Time between Failure (MTBF) measures.

Common managerial operating questions can be answered as exhibited for the provided circuit breaker population. This includes the longevity of field issues, the anticipated life cycle of a model or class, and AFTRER for models or classes of interest. These statistical analysis tools are used to make critical production quality and asset management observations and aid in decision‐making.

Due to limitations in existing database systems, the cost of events and explanatory variables related to event rates were not included in the analyses. There remains much work to be done in terms of the installation and retro‐fitting of breakers with conditions monitors in the field.

A framework to analyze maintenance data from fleet of similar assets using recurrent event data analysis is provided. The methods illustrated here would be useful for quality and asset managers to make operating decisions. This includes resource allocation decisions across a network of equipment.

Data analyzed are for power circuit breakers which are a critical element in the operation and reliability of the US power grid.

Using recurrent event data analysis to review and develop solutions to production quality and asset management problems including a comparison of AFTRER to FIR and MTBF measures.

In October of 1987 stock market prices all over the world fell by staggering amounts. A financial panic spreading beyond stock markets did not occur and it would appear that any real economic consequences of the crash have, thus far, been small. A superficial reading of economic history suggests that things might have turned out a whole lot worse. It is this thought that makes an evaluation of various restrictions designed to limit stock market volatility ‐ so called circuit breakers ‐ timely.

Using a case study for electrical power equipment, the purpose of this paper is to investigate the importance of dependence between series-connected system components in maintenance decisions.

A continuous-time Markov decision model is formulated to find a minimum cost maintenance policy for a circuit breaker as an independent component while considering a downstream transformer as a dependent component. Maintenance of the dependent component is included implicitly in terms of the costs associated with certain state-action pairs. For policy and cost comparisons, a separate model is also formulated that considers only the circuit breaker as the independent component. After uniformizing the continuous-time models to discrete time, standard methods are used to solve for the average-cost-optimal policies of each model.

The optimal maintenance policy and its cost differ significantly depending on whether or not the dependent component is considered.

Data used are from manufacturer databases; additional model validation could be conducted if applied to an electric utility asset fleet within their generation, transmission, and/or distribution system. This model and methodology are already being applied in other contexts such as industrial machinery and equipment, jet engines, amusement park rides, etc.

The outcome of this model can be utilized by asset and operations managers to make maintenance decisions based on prediction rather than more traditional time- or condition-based maintenance methodologies. This model is being developed for use as a module in a larger maintenance information system, specifically linking condition monitor data from the field to a predictive maintenance model. Similar methods are being applied to other applications outside the electrical equipment case detailed herein.

This model provides a structured approach for managers to decide how to best allocate their resources across a network of inter-connected equipment. Work in this area has not fully considered the importance of dependency on systems maintenance, particularly in applications with highly variable repair and replacement costs.

Power and communications wiring can be brought to computers and computer terminals in a variety of ways. Each method has its strengths and weaknesses; some that are ideal for one library may be forbidden another. Options include use of extension cords, perimeter raceway (such as conduit, wiremold, and armored cable), and interior raceway (such as underfloor duct, flat conductor cable, and power poles). Three sidebars discuss 1) the National Electrical Code; 2) volts, amps, watts, etc.; and‐3) transformers, circuit breakers, and circuits.