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Substation Equipment: Coupling Capacitors

Coupling Capacitors
Coupling capacitors are used to transmit communication signals to transmission lines. Some are used to measure the voltage in transmission lines. In signal transmission the coupling capacitor is part of a power line carrier circuit as shown in the schematic below. A coupling capacitor is used in this circuit in conjunction with a line trap. Line traps can be installed at the substation or on a transmission line tower.

Figure 1. Power line carrier schematic showing use of coupling capacitors
Figure 1. Power line carrier schematic showing use of coupling capacitors

Figure 2. Primary coupling capacitor
Figure 2. Primary coupling capacitor
Figure 3. Substation line traps
Figure 3. Substation line traps
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