Turn to the chapter on Motor Starting Characteristics . The handbook reminds you that a NEMA Design B motor draws 600% of full load current during locked rotor (starting). Check the breaker’s instantaneous trip setting. If it is set to 10x (standard) but the inrush peak is 12x, the breaker will trip. The solution: Use a time-delay fuse or a breaker with a higher instantaneous setting (e.g., 13x) or a soft starter, as detailed in the Coordination tables. Scenario 2: Substation Upgrade for Solar PV Problem: Adding a 5MW solar array to an existing 15kV switchgear line-up. The existing switchgear uses vacuum circuit breakers.
This article explores what the Switchgear and Control Handbook is, why it remains the most critical text in power engineering, the core principles it covers, and how modern professionals can leverage its wisdom to design safer, more reliable electrical systems. The Switchgear and Control Handbook is not a single, monolithic publication, but rather a class of authoritative technical manuals—most notably the seminal work by Robert W. Smeaton (and subsequent editions edited by William H. Howe). Published as part of McGraw-Hill’s standard handbooks for electrical engineers, this text is widely considered the "bible" of low and medium voltage power distribution. switchgear and control handbook
Whether you are designing a new data center, retrofitting a 1970s factory, or simply trying to figure out why a lighting panel keeps tripping, the answer is almost certainly coded within the covers of this handbook. It transforms a technician into an engineer and an engineer into a master of the electrical grid. For anyone who works within arms’ reach of live busbars, owning and studying the isn't optional—it is the first and last word in power protection. Turn to the chapter on Motor Starting Characteristics
Final Recommendation: Seek out the latest edition (currently the 5th or later, published by McGraw-Hill) and ensure it aligns with the current National Electrical Code (NEC) and IEEE standards. Keep it on your desk, not the shelf. If it is set to 10x (standard) but
Review the chapter on Generator and Inverter Interconnection . The handbook warns that inverter-based sources do not contribute to fault current in the same synchronous way, but they do create harmonic distortion and potential for ferroresonance with the switchgear’s CTs and VTs. It provides a checklist of required studies (insulation coordination, transient recovery voltage) before tapping the new line into the existing bus. Scenario 3: Arc Flash Labeling Problem: The facility safety manager demands an arc flash label for a 480V switchboard, but the electrician does not know where to find the "working distance" or "bolted fault current."
In the modern world, electricity is the silent lifeblood of industry, commerce, and daily life. From the massive turbines in a power plant to the final circuit breaker in a family home, a complex network of equipment manages, protects, and isolates electrical energy. At the heart of this network lies switchgear and control . For engineers, technicians, and project managers, navigating the complexities of voltage, arc flash, short circuits, and protective relaying requires more than on-the-job experience—it demands a definitive reference. That reference is the Switchgear and Control Handbook .