Five tips for designing an electrical system for safety

Isolate the circuit -- Electrical systems must be designed to support preventative maintenance, with easy access to the equipment. Designers need to make it easy to isolate equipment for repair with a disconnecting means that provides proper implementation of lock-out/tag-out procedures. Install disconnects with permanent lock-out provisions within sight of all motors and driven machinery.

Cover exposed components -- Use finger-safe(IP20) components and cover terminations of other parts in the equipment, where possible, to reduce potential contact with energized conductors. It is not always possible to de-energize the equipment before working on it. If energized metal components could be exposed during routine maintenance, covers, shields and insulating barriers must be used in accordance with safety standards. Specify electrical components that are finger-safe(IP20).

Limit the energy -- Circuits should also be designed to limit the available arc-flash energy. The use of current-limiting overcurrent devices can help to reduce the flash energy. This will provide improved protection for both equipment and employees. Use current-limiting fuses or current-limiting circuit breakers.

Retrofit -- If the electrical system is an existing fusible system, upgrade the fuses to the most current-limiting fuse types. This measure provides a much greater degree of current-limitation if an arc-flash incident occurs.

Training -- Obviously an important aspect of electrical safety is training. To be qualified, workers need training on the tasks and procedures (such as lock-out/tag-out procedures) that are essential to conducting their work in a safe manner. To motivate workers about the need for electrical safety, and recognizing the associated hazards, Cooper Bussmann offers a Trainers Module Safety Basics program (Part SBK), which includes a video, a Safety Basics Handbook, PowerPoint presentations and more. This Trainers Kit can be ordered from a Bussmann electrical distributor.

Information taken from Cooper Bussmann’s Safety BASICs training program.

Back to top

Back to Web-exclusive articles archives