Starting with Part III of Article 220, which is titled Feeder and Service Load Calculation, we will finally start with the actual math work.
Single-phase and three-phase AC squirrel cage induction motors need some type of circuit to initiate a start or stop function. Usually single-phase motors and smaller horsepower three-phase motors can be started with full voltage across the line. However, larger horsepower three-phase motors require reduced voltage starting techniques.
The world is changing rapidly and becoming more dependent than ever on expanded use of alternative energy systems and reducing and preserving grid-produced energy.
UL has created two new wind turbine certification product categories, Wind Turbine Drive-train Systems and Equipment (ZGDT) and Wind Turbine Tower Assemblies (ZGTA)
UL does certify PV module trackers under the product category Photovoltaic Solar Trackers (QIKA)