Phase-over-phase switches provide very economical sectionalizing and circuit control at tap and tie switching points. Mounted on a single pole structure in the line, their use can minimize line right-of-way requirements and significantly reduce the costs of land and equipment associated with conventional substation switching.
Phase-over-phase GOABS® utilize side-break style switches, mounted horizontal upright on aluminum and/or steel support structures. The switch is designed for maintenance-free operation in severe environmental and operating conditions. The operating effort to open and close the switch is minimal, even at higher voltages; no slamming is ever required. The switch is positively toggled when in the fully closed position, so the switch stays closed under adverse conditions, such as excessive pole deflection, vibration, and galloping conductors, without the use of blade locks or other latching devices.
Tie and Tap Switching - the economics of 'bundling'
Two-way and three-way phase-over-phase switches employ a multiple-switch concept where individual switch pole units are arranged in an integral design, sharing insulators, interrupters, and other switch components. Because components are shared, the cost of switching becomes proportionally less expensive when compared to other conventional switch configurations.
In addition, the combining of two or three switches into one 'bundle' provides a single location for tap or tie circuit control, whether local, remote, or automatic. This facilitates the addition and use of automation equipment, such as motor operators, rtu's, and line sensors, which support switch operation through supervisory control or auto-sectionalizing. Like the sharing of switch components, the sharing of automation equipment makes the cost of control proportionally less expensive.