Steel lattice towers are also used in electronic and communication industries for communication of microwave signals through different types of antennas. Several antennae are fixed on the tower in different directions at different heights as per the requirement and usage. The antenna positions decide the height of the tower. Symmetrical cross sections are preferred for microwave towers due to reversal of wind direction. Generally steel lattice towers with square or triangular plan are used for microwave towers. Angle sections and tubes are commonly used for the fabrication of these towers. Microwave towers are generally self-supporting steel lattice towers. Guyed towers are also used for microwave communication, but are least preferred for supporting heavy disc antennae. Wind load on the tower body and antennae is the major load on the structure besides the self-weight of the tower. Microwave towers are generally supported either at ground or at rooftop of some buildings. The tip deflection of the tower is a governing parameter for the functional requirement. Typical configuration of a 102-m high microwave tower is shown in Figure. The tower is triangular in plan. The two-dimensional and three-dimensional views of the tower are shown.
Breaker Schemes in Substations — Types, Design, Advantages, Disadvantages, and Comparison Author: Engr. Aneel Kumar Figure 1: Infographic overview of breaker schemes commonly used in substations. Introduction The breaker scheme or busbar arrangement in a substation defines how incoming feeders, outgoing feeders, and power transformers are connected to the bus. The choice of scheme has a direct impact on system reliability, maintainability, safety, and cost . A simple bus scheme is economical but vulnerable to outages, while advanced schemes such as breaker-and-a-half or double-bus/double-breaker provide very high reliability but at much higher cost and design complexity. Engineers select breaker schemes considering fault tolerance, maintenance needs, space requirements, expansion possibilities, protection coordination, and capital investment . Below, we explain eac...
Comments