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| Figure 6-11 Application of IL and SL transformers. |

| Other Customer-Type Transformers. |

| Where voltages of a value other than that of the supply source are required or desired for safety and operating reasons, transformers or autotransformers are employed. Some examples, by no means complete, are given below. |

| Sign Lighting |

| Signs made of luminous gas tubes require higher voltages than the usual normal secondary distribution supply and are essentially constant-current devices. The impedance of the tube increases as the length increases and is higher for a tube of small diameter than for one of larger diameter. Hence, the transformer chosen should deliver the proper current and voltage for the tube. For small signs, an autotransformer may be used. For larger signs, where the applied voltage may be several thousand volts in magnitude, a two-winding transformer is used with the midpoint of the high-voltage secondary |

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