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Page 358

| Figure 17-23 (cont.) Typical recording meters: (D) kilovolt-ampere demand meter. |

| it is desirable to isolate one circuit electrically from another. For additional information regarding CTs, refer to Chap. 6. |

| Potentiometers and Potential Transformers |

| If the values of voltage involved might exceed the range of the instruments, two schemes are used to measure only a smaller but critical proportion of the total voltage. Either potentiometer or a potential transformer may be used for this purpose. |

| A potentiometer (sometimes called a multiplier) consists of a coil of very high resistance connected across a line. A voltmeter is connected across a |

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