572 STANDARD ELECTRICAL DICTIONARY.W.(a) A symbol or abbreviation for watt.(b) A symbol or abbreviation for work.(c) A symbol or abbreviation for weight.Wall Bracket.A telegraph bracket to be attached to the external walls of buildings towhich wires are attached as they come from the poles to reachconverters, or for direct introduction into a building.Wall Sockets.Sockets for incandescent lamps constructed to be attached to a wall.Ward.Direction in a straight line; a term proposed by Prof. James Thompson.The words "backward" and "forward" indicate its scope.Water.A compound whose molecule consists of two atoms of hydrogen and one atomof oxygen; formula, H2 O.Its specific gravity is 1, it being the base of the system of specificgravities of solids and liquids.If pure, it is almost a non-conductor of electricity. If any impurity ispresent it still presents an exceedingly high, almost immeasurable trueresistance, but becomes by the presence of any impurity an electrolyte.Water Equivalent.In a calorimeter of any kind the weight of water which would be raisedas much as is the calorimeter with its contents by the addition of anygiven amount of heat received by the calorimeter.Waterproof Lamp Globe.An outer globe for incandescent lamps, to protect them from water.Watt.(a) The practical unit of electric activity, rate of work, or rate ofenergy. It is the rate of energy or of work represented by a current ofone ampere urged by one volt electro-motive force; the volt-ampere.It is the analogue in electricity of the horse power in mechanics;approximately, 746 watts represent one electric horse power.Ohm's law, taken as C = E/R, gives as values for current, C and E/R, andfor electro- motive force C R. In these formulas, C represents currentstrength, R represents resistance and E represents electro-motive force.Then a watt being the product of electro-motive force by currentstrength, we get the following values for rate of electric energy, ofwhich the watt is the practical unit: (1) E2/R -- (2) C*E -- (3) C2 * R.The equivalents of the watt vary a little according to differentauthorities. Ayrton gives the following equivalents: 44.25 foot poundsper minute--.7375 foot pounds per second--1/746 horse power. Thesevalues are practically accurate. Hospitalier gives .7377 foot pounds persecond. Hering gives .737324 foot pounds per second, and 1000/745941horse power.573 STANDARD ELECTRICAL DICTIONARY.It is equal to 1E7 ergs per second.Synonym--Volt-ampere.(c) It has been proposed to use the term as the unit of energy, insteadof activity or rate of energy (Sir C. W. Siemens, British Association,1882); this use has not been adopted and may be regarded as abandoned.[Transcriber's note; Watt is a unit of POWER--energy per unit of time.]Watt-hour.A unit of electric energy or work; one watt exerted or expended for onehour.It is equivalent to :866.448 gram-degrees C. (calories)2654.4 foot lbs.3600 watt-seconds or volt-coulombs.60 watt-minutes.Watt-minute.A unit of electric energy or work; one watt exerted or expended for oneminute.It is equivalent to14.4408 gram-degrees C. (calories),44.240 foot pounds,60 watt seconds or volt-coulombs,1/60 watt hour.Watts, Apparent.The product in an alternating current dynamo of the virtual amperes bythe virtual volts. To give the true watts this product must bemultiplied by the cosine of the angle of lead or lag. (See Current,Wattless.)[Transcriber's note: This is now called a volt-amp. The usual usage isKVA, or kilovolt-ampere.]Watt-second.A unit of electric energy or work. One watt exerted or expended for onesecond.It is equivalent to.24068 gram degree C. (calorie),.000955 lb. degree F.,.737337 foot lbs.,.0013406 horse power second (English),.0013592 horse power second (metric).Synonym--Volt-coulomb.Waves, Electro-magnetic.Ether waves caused by electromagnetic disturbances affecting theluminiferous ether. (See Discharge, Oscillatory--Maxwell's Theory ofLight--Resonance. Electric.)[Transcriber's note: The Michaelson-Morley experiment (1887) had alreadycalled ether into question, but quantum theory and photons are decadesin the future.]574 STANDARD ELECTRICAL DICTIONARY.Weber.(a.) A name suggested by Clausius and Siemens to denote a magnet pole ofunit strength. This use is abandoned.(b.) It has been used to designate the unit of quantity--the coulomb.This use is abandoned.(c.) It has been used to designate the unit of current strength theampere. This use is abandoned.[Transcriber's note: Definition (a) is now used. One weber of magneticflux linked to a circuit of one turn produces an electromotive force of1 volt if it is reduced to zero at a uniform rate in 1 second.]Weber-meter.An ampere-meter or ammeter. The term is not used since the term "weber,"indicating the ampere or coulomb, has been abandoned.Welding, Electric.Welding metals by heat produced by electricity. The heat may be producedby a current passing through the point of junction (Elihu Thomson) or bythe voltaic arc. (Benardos & Olzewski.)Fig. 346. ELECTRIC WELDING INDUCTION COIL.The current process is carried out by pressing together the objects tobe united, while holding them in conducting clamps. A heavy current isturned on by way of the clamps and rapidly heats the metals at thejunction, which is of course the point of highest resistance. As themetal softens, it is pressed together, one of the clamps being mountedwith feed motion, flux is dropped on if necessary, and the metal piecesunite.The most remarkable results are thus attained; almost all common metalscan be welded, and different metals can be welded together. Tubes andother shapes can also be united. In many cases the weld is the strongestpart.575 STANDARD ELECTRICAL DICTIONARY.The alternating current is employed. A special dynamo is sometimes usedto produce it. This dynamo has two windings on the armature. One is offine wire and is in series with the field magnets and excites them. Theother is of copper bars, and connects with the welding apparatus, givinga current of high intensity but actuated by low potential.Where the special dynamo is not used, an induction coil or transformeris used. The primary includes a large number of convolutions ofrelatively fine wire; the secondary may only be one turn of a largecopper bar.The cut shows in diagram an electric welding coil. P is the primary coilof a number of turns of wire; S S is the secondary, a single copper barbent into an almost complete circle. It terminates in clamps D D forholding the bars to be welded. B C, B' C are the bars to be welded. Theyare pressed together by the screw J. The large coil I of iron wiresurrounding the coils represents the iron core.The real apparatus as at present constructed involves manymodifications. The diagram only illustrates the principle of theapparatus.In welding by the voltaic arc the place to be heated is made anelectrode of an arc by connection with one terminal of an electriccircuit. A carbon is connected to the other terminal. An arc is startedby touching and withdrawal of the carbon. The heat may be used forwelding, soldering, brazing, or even for perforating or dividing metalsheets.Welding Transformer.The induction coil or transformer used in electric welding. For itsgeneral principles of construction, see Welding, Electric.Wheatstone's Bridge.A system of connections applied to parallel circuits, includingresistance coils for the purpose of measuring an unknown resistance. Asingle current is made to pass from A through two parallel connectedbranches, joining together again at C. A cross connection B D has agalvanometer or other current indicator in circuit. In any conductorthrough which a current is passing, the fall of potential at givenpoints is proportional to the resistance between such points. Referringto the diagram a given fall of potential exists between A and C. Thefall between A and B is to the fall between A and C as the resistance rbetween A and B is to the resistance r + r' between A and C. The sameapplies to the other branch, with the substitution of the resistances sand S' and the point D for r r' and B. Therefore, if this proportionholds, r : r' : : s : S'. No current will go through B D , and thegalvanometer will be unaffected. Assume s' to be of unknown resistance,the above proportion will give it, if r, r' and s are known, or if theratio of r to r' and the absolute value of s is known.576 STANDARD ELECTRICAL DICTIONARY.In use the resistances r, r', and s are made to vary as desired. Tomeasure an unknown resistance it is introduced at S', and one of theother resistances is varied until the galvanometer is unaffected. Thenthe resistance of S' is determined by calculation as just explained. Theartificial resistances may be resistance coils, q. v., or it is enoughto have one unknown resistance at s. Then if the length of wire ABC isaccurately known, the point B can be shifted along it until the balanceis attained. The relative lengths A B, and B C, will then give the ratior : r' needed for the calculation. This assumes the wire ABC to be ofabsolutely uniform resistance. This is the principle of the meter-bridgedescribed below. The use of coils is the more common method and iscarried out by special resistance boxes, with the connections arrangedto carry out the exact principle as explained. The principle ofconstruction and use of a resistance box of the Wheatstone bridge type,as shown in the cut, is described under Box Bridge, q. v.FIG. 347. WHEATSTONE BRIDGE CONNECTIONS.FIG. 348. TOP OF BOX BRIDGE.577 STANDARD ELECTRICAL DICTIONARY.The next cut shows the sliding form of bridge called the meter bridge,if the slide wire is a meter long or a half- or a quarter-meter bridge,etc., according to the length of this wire. It is described under MeterBridge, q. v. Many refinements in construction and in proper proportionof resistances for given work apply to these constructions.Synonyms--Electric Balance--Resistance Bridge--Wheatstone's Balance.Fig. 349. METER BRIDGE.Whirl, Electric.(a) A conductor carrying an electric current is surrounded by circularlines of force, which are sometimes termed an electric whirl.(b) The Electric Flyer. (See Flyer, Electric.)Wimshurst Electric Machine.An influence machine for producing high potential or static electricity.Two circular discs of thin glass are mounted on perforated hubs orbosses of wood or ebonite. Each hub has a groove turned upon it toreceive a cord. Each disc is shellacked. They are mounted on ahorizontal steel spindle so as to face and to be within one-eighth of aninch of each other. On the outside of each disc sixteen or eighteensectors of tinfoil or thin metal are cemented.578 STANDARD ELECTRICAL DICTIONARY.Two curved brass rods terminating in wire brushes curved into asemi-ellipse just graze the outer surfaces of the plates with theirbrushes. They lie in imaginary planes, passing through the axis of thespindle and at right angles from each other.Four collecting combs are arranged horizontally on insulating supportsto collect electricity from the horizontal diameters of the discs. Theselie at an angle of about 45° with the other equalizing rods. Dischargingrods connect with the collecting combs.The principle of the machine is that one set of sector plates act asinductors for the other set. Its action is not perfectly understood.It works well in damp weather, far surpassing other influence machinesin this respect. On turning the handle a constant succession or streamof sparks is produced between the terminals of the discharging rods.Windage.In a dynamo the real air gap between the armature windings and polepieces is sometimes thus termed.Wind, Electric.The rush of air particles from a point connected to a statically chargedcondenser.Winding, Compound.A method of winding a generator or motor in which a shunt winding isused for the field magnets and in which also a second winding of themagnet is placed in series with the outer circuit. (See Winding,Series--Winding, Shunt.)Fig. 350. CHARACTERISTIC CURVES OF SHUNT AND SERIES WINDING.The object of compound winding is to make a self-regulating dynamo andthis object is partly attained for a constant speed.The characteristic curves of shunt and series winding are of oppositenatures. The first increases in electro-motive force for resistance inthe outer circuit, the latter decreases under the same conditions. Ifthe windings are so proportioned that these conditions for each one ofthe two windings are equal and opposite, it is evident that thecharacteristic may be a straight line. This, however, it will only be ata single speed of rotation.579 STANDARD ELECTRICAL DICTIONARY.Winding, Disc.A winding which (S. P. Thompson) may be treated as a drum windingextended radially, the periphery corresponding to the back end of thedrum. The magnet poles are generally placed so as to face the side orsides of the disc.Winding, Lap.A method of winding disc and drum armatures. It consists in lapping backeach lead of wire towards the preceding lead upon the commutator end ofthe armature. Thus taking the letter U as the diagrammaticalrepresentation of a turn of wire in connecting its ends to thecommutator bars they are brought towards each other so as to connectwith contiguous commutator bars. This carries out the principle ofkeeping the two members of the U moving in regions of opposite polarityof field, so that the currents induced in them shall have oppositedirections, thus producing a total current in one sense through the bentwire.Winding, Long Shunt.A system of compound winding for dynamos and motors. The field is woundin series and, in addition thereto, there is a shunt winding connectedacross from terminal to terminal of the machine, and which may beregarded either as a shunt to the outer circuit, or as a shunt to theseries-field and armature winding. (See Winding, Short Shunt.)Synonyms--Series and Long Shunt Winding.Winding, Multiple.A winding of an electro-magnet, in which separate coils are wound on thecore, so that one or any number may be used as desired in parallel or inseries. For each coil a separate binding post should be provided.Winding, Multipolar.Winding adapted for armatures of multi-polar dynamos or motors.Winding, Series.A method of winding a generator or motor, in which one of thecommutator-brush connections is connected to the field-magnet winding;the other end of the magnet winding connects with the outer circuit. Theother armature-brush connects with the other terminal of the outercircuit.Winding, Series and Separate Coil.A method of automatic regulation applied to alternating current dynamos.Winding, Short Shunt.A method of compound winding for dynamos and motors. The field is woundin series, and in addition thereto there is a shunt winding connectedfrom brush to brush only, thus paralleling the armature. (See Winding,Long Shunt.)Synonyms--Series and Short Shunt Winding.580 STANDARD ELECTRICAL DICTIONARY.Winding, Shunt.A method of winding a generator or motor. Each commutator-brush has twoconnections. One set are the terminals of the outer circuit, the otherset are the terminals of the field-magnet windings. In other words, thefield-magnet windings are in shunt or in parallel with the outercircuit.Winding, Shuttle.A method of dynamo or motor-armature winding. A single groove passeslongitudinally around the core and in this the wire is continuouslywound. The system is not now used. The old Siemens' H armatureillustrates the principle.Winding, Wave.A method of winding disc and drum armatures. It consists in advancingthe commutator ends of the U shaped turns progressively, so that as manycommutator bars intervene between any two consecutive commutatorconnections of the wire as there are leads of wire on the drum betweenconsecutive leads of the wire. This is carried out with due regard tothe principle that taking the letter U as the diagrammaticalrepresentation of a turn of wire, its two members must move throughregions of the field of opposite polarity.Wire Finder.A galvanometer or other instrument used for identifying the ends of agiven wire in a cable containing several.Work.When a force acts upon a body and the body moves in the direction of theforce, the force does work. Hence, work is the action of a force throughspace against resistance.It is generally expressed in compound units of length and weight, asfoot-pounds, meaning a pound raised one foot.Work, Electric, Unit of.The volt-coulomb, q. v., or watt-second, as it is often termed.Working, Diode.In multiplex telegraphy the transmission of two messages,simultaneously, over one wire. (See Telegraphy, Multiple.)Working, Contraplex.A variety of duplex telegraphy in which the messages are sent fromopposite ends of the line, simultaneously, so as to be transmitted inopposite directions. (See Working, Diplex.)Working, Diplex.In duplex telegraphy the sending of two independent messages from thesame end of the line in the same direction.581 STANDARD ELECTRICAL DICTIONARY.Working, Double Curb.A method of working telegraph lines. When a signal is sent the line ischarged. This has to be got rid of, and is an element of retardation. Indouble curb working it is disposed of by sending a momentary currentfirst in the reverse, and then in the same, and finally in the reversedirection. This is found to reduce the charge to a very low point.Working, Hexode.In multiplex telegraphy the transmission of six messages simultaneouslyover one wire. (See Telegraphy, Multiplex.)Working, Pentode.In multiplex telegraphy the transmission of five messages simultaneouslyover one wire. (See Telegraphy, Multiplex.)Working, Reverse Current.A method of telegraphy, in which the currents are reversed or alternatedin direction.Working, Single Curb.A simpler form of telegraph signaling than double curb working. Itconsists in sending a reverse current through the line for each signalby reversing the battery connection.Working, Tetrode.In multiplex telegraphy the transmission of four messages simultaneouslyover the same line. (See Telegraphy, Multiplex.)Working, Triode.In multiplex telegraphy the transmission of three messagessimultaneously over the same wire. (See Telegraphy, Multiplex.)Work, Unit of.The erg, q. v. It is the same as the unit of energy, of which work isthe corelative, being equal and opposite to the energy expended in doingit. There are many other engineering units of work, as the foot-poundand foot-ton.Yoke.In an electro-magnet, the piece of iron which connects the ends furthestfrom the poles of the two portions of the core on which the wire iswound.Zamboni's Dry Pile.A voltaic pile or battery. It is made of discs of paper, silvered ortinned on one side and sprinkled on the other with binoxide ofmanganese. Sometimes as many as 2,000 of such couples are piled up in aglass tube and pressed together with two rods which form the terminals.They maintain a high potential difference, but having very highresistance and slight polarization capacity, give exceedingly smallquantities.Zero.(a) The origin of any scale of measurement.(b) An infinitely small quantity or measurement.582 STANDARD ELECTRICAL DICTIONARY.Zero, Absolute.From several considerations it is believed that at a certain temperaturethe molecules of all bodies would touch each other, their kinetic motionwould cease, and there would be no heat. This temperature is theabsolute zero. It is put at -273° C. (-459° F.)[Transcriber's note; The modern value is 0
°
Kelvin, -273.15
°
C, or-459.67
°
F. The lowest reported temperature observed is 1E-10
°
K.]Zero, Potential.Conventionally, the potential of the earth. True zero potential couldonly exist in the surface of a body infinitely distant from otherelectrified bodies.Zero, Thermometric.There are three thermometric zeros. In the Réaumur and centigradescales, it is at the temperature of melting ice; in the Fahrenheitscale, it is 32° F. below that temperature, or corresponds to -17.78° C.The third is the absolute zero. (See Zero, Absolute.)Zinc.A metal; one of the elements; atomic weight, 65.1;specific gravity, 6.8 to 7.2.microhms.Resistance at 0° C. (32° F.), per centimeter cube, 5.626Resistance at 0° C. (32° F.), per inch cube, 2.215Relative resistance (silver = 1), 3.741ohms.Resistance of a wire, 1 foot long, weighing 1 grain, .5766(a) 1 foot long, 1 millimeter diameter, 33.85(b) 1 meter long, weighing 1 gram, .4023(c) 1 meter long, 1 millimeter diameter, .07163Zinc is principally used in electrical work as the positive plate involtaic batteries.Zincode.The terminal connecting with the zinc plate, or its equivalent in anelectric circuit; the negative electrode; the kathode. A term now littleused.Zinc Sender.An apparatus used in telegraphy for sending a momentary reverse currentinto the line after each signal, thus counteracting retardation.Zone, Peripolar.In medical electricity, the region surrounding the polar zone, q. v.Zone, Polar.In medical electricity, the region surrounding the electrode applied tothe human body.