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Page 317

| Figure 16-5 Capacitor installation on poles. |

| stop, for example), capacitors may be connected or disconnected from the system in order to supply just enough capacitance (approximately) to cancel out the inductance of the system. Banks of capacitors may be switched on and off by means of time-clocks, by over- and under-voltage relays, or by other devices. |

| One relatively large block of capacitance that is almost continually connected to electrical systems is that of underground cables, especially those with metallic sheaths. |

| Capacitors connected in parallel with loads correct the component of current caused by inductive reactance. Capacitors connected in series with the line compensate for the reactive voltage drop in the circuit. Although shunt capacitors are used widely for power-factor correction, series capacitors are used in low-voltage, heavy-current applications, such as furnaces and welders, to compensate for the voltage drop in the conductors. Series capacitors are also used in high-voltage transmission lines to compensate for the voltage drop caused by inductive reactance and to increase the amount of power transmitted. |

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