Clearing procedures in electrical installations: the electrical status space as model for training and planning

Maintenance personnel must take the clearing procedures, operating the necessary steps to assure that the system or portion of the system on which they plan to work is in an electrically safe working condition. Complexity of the electrical system normally determines the level of detail required for planning the system clearing procedures. The clearing procedures should be completely written, checked, and understood by all persons involved before applying them to any portion of the power distribution system. This paper reviews and enhances previous papers. It investigates the basic concepts and definitions to give prominence to operating bonds and to help the procedure/project with alternative, independent ways. It proposes some simple rules and bond definitions to facilitate programming. It introduces a graphical representation and a logic code to write symbolically the electrical status. Both intuitive and mathematical approaches can heighten understanding. The model allows memorizing visually the logic procedures, counting the necessary locks, and executing an autocheck of the clearing procedure.