Design changes in new electrical transformer
August 20, 2009 by Windpower Engineering
Filed under Electrical Systems
The manufacturer of a dry electrical transformer has developed a cost-effective general purpose, encapsulated-transformer line for commercial applications. Designated the HPS Fortress by developer Hammond Power Solutions, Baraboo, WI, the designs feature a NEMA 3R rated enclosure and are encapsulated with electrical-grade silica sand and resin compounds to completely enclose the core and coil. This seals out moisture and airborne contaminants while eliminating corrosion and deterioration. The HPS Fortress meets ANSI standards for indoor and outdoor applications. The transformer has a rear and side entry conduit knockout for easy access into a roomy wiring compartment. The transformer comes in nine standard single-phase and eight standard three-phase voltage groups.
The single-phase design is available from 50 VA to 37.5 kVA and features a standard shield for units 750 VA and up. Wall mounting is standard on units up to 25 kVA and is available for 37.5 kVA units.
The three-phase design is available from 2 kVA to 75 kVA and features a standard shield on all units. Wall mounting is standard for units up to 9 kVA and optional for the 15 kVA, 30 kVA and 45 kVA units. The HPS Fortress design is available in custom 
voltage, frequency, shielding and mounting options to meet application requirements.
Steel poles for transmission lines
May 16, 2009 by Paul Dvorak
Filed under Electrical Systems, Materials, Utility Grid
Sabre Tubular Structures offers a light duty line of standard class poles designed to ANSI requirements. These poles satisfy the needs of cooperatives governed by RUS requirements, and investor-owned utilities that specify a “wood-pole equivalent” structure. Concerns regarding severe weather, woodpecker damage, accessibility issues in remote areas, and simple environmental issues have increased the need to replace wood poles with steel versions.
The company also provides an interactive MS Excel-based worksheet that lets users input basic design criteria, such as required height and embedment depth. The software then calculations a design for each pole class ranging from Class 3 to Class H9. In addition, input fields for fixity point below ground and “near pole top” lets users review diameter and moment capacity at each location to determine the pole class best suited to a project.
