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Feeder busway is used to interconnect equipment, such as between a transformer and a switchgear line up. A variant type is a low-impedance busway, which is designed to have lower voltage drop by virtue of close spacing of bus bars, which reduces inductive reactance. A trolley busway provides power to equipment that must be frequently moved.
Stubs can match a load impedance to the transmission line characteristic impedance. The stub is positioned a distance from the load. This distance is chosen so that at that point, the resistive part of the load impedance is made equal to the resistive part of the characteristic impedance by impedance transformer action of the length of the main ...
Hence, a line trap unit is inserted between the busbar and connection of coupling capacitor to the line. It is a parallel tuned circuit containing inductance and capacitance. It has low impedance for power frequency and high impedance to carrier frequency. This unit prevents the high frequency carrier signal from entering the neighboring line. [4]
A low impedance load (e.g. leaving the end open in free air) will cause a reflected wave in which the sign of the pressure variation reverses, but the direction of the pressure wave remains the same. A load that matches the characteristic impedance (defined below) will completely absorb the wave and the energy associated with it.
Impedance matching is important when components of an electric circuit are connected (waveguide to antenna for example): The impedance ratio determines how much of the wave is transmitted forward and how much is reflected. In connecting a waveguide to an antenna a complete transmission is usually required, so an effort is made to match their ...
For many systems, the terminator is a resistor, with a value chosen to match the characteristic impedance of the transmission line and chosen to have acceptably low parasitic inductance and capacitance at the frequencies relevant to the system. Examples include 75-ohm resistors often used to terminate 75-ohm video transmission coaxial cables.
Impedance (Z) parameter may defines by applying a fixed current into one port (I1) of a transmission line with the other port open and measuring the resulting voltage on each port (V1, V2) [8] [9] and computing the impedance parameter Z11 is V1/I1, and the impedance parameter Z12 is V2/I1. Since transmission lines are electrically passive and ...
The characteristic impedance of a line is the impedance encountered by a wave travelling along the line; it depends only on the line geometry and materials and is not changed by the line termination. It is necessary to match the characteristic impedance of the planar line to the impedance of the systems to which it is connected.