The investigation of malfunctions and failures in electrical systems

The malfunction or failure of an electrical system because unintentional signal or power flow paths were incorporated in the electrical circuit design is known to be the cause of several major failures of engineering systems. These unintentional signal or power paths are known as sneak circuits. The nature of sneak circuits was first considered after they had been identified as the cause of some spectacular and expensive rocket failures in the United States space programme. This paper reviews the status of sneak circuit analysis (SCA) and presents a general systematic method the author has devised to identify sneak circuits. The application of the method of SCA is illustrated with a case study. The paper makes a case to take the investigation of an electrical failure or malfunction beyond the identification of a failed component to include a search for possible sneak circuits. The obvious fact that could result from the discovery of a sneak circuit is the shift in legal responsibility from the component manufacturer to the circuit designer.

Keywords:

• Sneak Circuit
• Sneak Path
• Sneak Circuit Analysis
• Design Concern Analysis
• Electrical Failure