Modern Wiring Diagrams and Descriptions: A Handbook of Practical Diagrams and Information for Electrical Construction Work, Showing at a Glance All that Ordinary Electrical Workers Need and Nothing that They Do Not NeedF. J. Drake & Company, 1918 - 287 σελίδες |
Συχνά εμφανιζόμενοι όροι και φράσεις
alternating current ammeter amperes ance annunciator arc lamp armature circuit arranged battery wire bell binding post brushes burglar alarm burn bus bars candle-power carry cells circuit breaker closes the circuit commutator connected in series controller cuit current flowing current passes cutout diagram direct current direct-current double-throw switch dynamo Electric energized equal field and armature floor fuses galvanometer ground detector incandescent lamps increases induction coil inserted light load lower machine magnet main switch meter method moved nected nection negative neutral wire open circuit opening the circuit operated parallel placed plug polarity pole position push buttons rent resistance box reversing switch rheostat ring rotor series fields short circuit shown in Figure shows the connections shunt field side solenoid spark speed starting box station switch shown terminals tery three phase thrown tion transformer tube upper voltage voltmeter volts wattmeter watts Wheatstone bridge wire leads
Δημοφιλή αποσπάσματα
Σελίδα 95 - The area of a circle is found by multiplying the square of the diameter by .7854, or the square of the radius by 3.1416.
Σελίδα 117 - FIG. 668 the carbons, and regulates the arc so gradually that a perfect, steady arc is maintained. The fine wire of the magnets is connected in series with the winding of a small auxiliary cut-out magnet at the top of the mechanism. This magnet, which also has a supplementary coarse winding, does not raise its armature unless the voltage at the arc increases to 70 volts. The two windings connect at the inside terminal on the lower side of the auxiliary cutout magnet, and the current from the fine...
Σελίδα 117 - ... connect at the inside terminal on the lower side of the auxiliary cut-out magnet, and the current from the fine wire of the main magnets passes through both windings and then to the cut-out block and so to the starting resistance and out. If the main current through the carbon is interrupted (as by breaking of the carbons), the whole current of the lamp passes through the fine wire circuit. Before this excessive current has time to overheat the fine wire circuit, it energizes the auxiliary cut-out...
Σελίδα 117 - The fine wire winding is connected in the opposite direction from the coarse wire winding, and its attraction is therefore opposite. When the arc increases in length, its resistance increases, and consequently the current in the fine wire is increased. The attraction of the coarse wire winding is therefore partly overcome and the armature begins to fall. As it falls, the arc is shortened and the current in the fine wire decreases. The mechanism feeds the carbons and regulates the arc so gradually...
Σελίδα 118 - ... been burning for some time on direct current the carbons assume the shape shown in Fig. 88, the upper or positive carbon assuming a cup shape, while the lower carbon generally burns to a point. This cup shape formation on the upper or positive carbon acts as a reflector to throw the light downward. The positive carbon burns away about twice as fast as the negative carbon and lamps must be trimmed accordingly. Sometimes the current feeding arc lamps (on direct current systems) becomes reversed,...
Σελίδα 93 - The Reciprocal of a number is 1 divided by that number. Thus the reciprocal of 5 is » ; of 12, ,>, ; of 240, 2>5, etc.
Σελίδα 186 - ... current being rectified by means of the commutator C. This commutator has as many segments as there are poles to the dynamo, and the alternate segments are connected together as shown in the small diagram. S is a German silver resistance which is connected in shunt across this rectifying commutator. The main current coming from the armature is shunted, part going through the shunts, the remainder around the field winding. It will be seen that this method of field excitation is' very similar to...
Σελίδα 175 - ... closed at the same time, or preferably a little before the mains are closed. In some cases the middle, or equalizer, blade of the dynamo switch is made longer than the outside to accomplish this. The series fields are often regulated by a shunt of variable resistance. To insure the best results compound machines should be run at just the proper speed, otherwise the proportions between the shunt and series coils are disturbed. GENERAL RULES 1. Be sure that the speed of the dynamo is right. 2....
Σελίδα 237 - ... of the second. At each side of the name plate (at 3, for instance) there are three holes. The large hole is used for the permanent connection, while the smaller holes are used for transferring circuits, without shutting down the dynamo. Smaller cables and plugs are used for transferring. If it is desired to cut off circuit 5 from machine 4, a plug is inserted in one of the small holes at the right of 4, the other plug being inserted in one of the holes at the left of 7. Circuit 5 would now be...
Σελίδα 189 - For 1,150 volt machine, omit connections A to B, C to D, E to F, and G to H, and connect as shown by dotted lines. The armature of a standard monocyclic alternator rotates in a counter clockwise direction facing the commutator. When the alternator is loaded, the voltage between the teazer coil and the two terminals of the main coil may be different ; therefore, it is necessary to have the commutator connected in corresponding ends of the main coil. If the machine has not been arranged for clockwise...