Chapter 9

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                                                Chapter 9

                                                                             EG = 180 V

                        G                            M           V           I = 20 A
                                   584’ wire
                                                                             V = 176.4 V

1. Refer to the drawing above;
           a. If the current is 35 amperes, what is the voltage applied to the motor? _____________
           b. Determine the line drop if the wire length is 812 feet. ______________________
           c. If the resistance is 0.4 ohm per thousand feet, with 584 feet required, what is the
               voltage applied to the motor? _______________________________
2. A DC motor draws 100 amperes at full load from a 220 volt DC source 200 feet away. If a 3% line
   voltage loss is permissible, find the wire size to be used for the line conductors. K = 12.9
3. A 110 volt DC source supplies 25 amperes to a load circuit 500 feet away. No. 10 copper wires are
   used for line conductors. K = 12.6
           a. The line drop is ________________________________
           b. Voltage at the load is ___________________________
           c. If No. 8 copper wire is used, what is the voltage at the load? ____________________
4. The annoying effect of dimming lights in a home sometimes occurs when a device is connected to
   the line and it has a value of resistance that is _____________________________
5. For a small line voltage drop, the resistance of line conductors should be _____________________.
6. When a permitted percentage of line voltage drop is specified in a problem, the value is computed
   directly from the _______________________________________________
7. The voltage that is applied to a load is equal to __________________________________________
8. Line voltage is inversely proportional to the ____________________________________________
9. Two general factors that must be considered when selecting conductors are permissible voltage
   drop and ___________________________________________________

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