B
B. An abbreviation for Beaumé, the inventor of the hydrometer scale. Thus, in speaking of the gravity of fluids, 20° B. means twenty degrees Beaumé.
Back Induction. A demagnetizing force produced in a dynamo when a lead is given to the brushes. (See also [Induction, Back].)
Back Shock. A lightning stroke received after the main discharge. It is caused by a charge induced in neighboring surfaces by the main discharge.
Bad Earth. A poor ground connection, or one having comparatively strong electrical resistance.
Balance. A proper adjustment between the apparatus and the electro-motive force, thus securing the best possible results.
B. & S. W-G. Abbreviations for Brown & Sharp and wire-gauge, and referring to the sizes of wire and sheet-metal thicknesses that are considered standards in America.
Bar-armature. An armature in which the conductors are constructed of bars.
Bar-magnet. One whose core presents the appearance of a straight bar, or rod, without curve or bend.
Bare-carbons. Electric light carbons whose surfaces are not electro-plated with copper.
Barometer. An apparatus for measuring the pressure exerted by the atmosphere. It consists of a glass tube 31 inches long, closed at one end, filled with mercury, and then inverted, with its open end immersed in a cistern of mercury. The column of mercury falls to a height proportional to the pressure of the atmosphere. At the sea-level it ranges from 30 to 31 inches.
Bar-windings. The windings of an armature constructed of copper bars.
Bath. In electro-plating, the solution or electrolyte used for depositing metal on the object to be plated. It may be a solution of copper, silver, nickel, or other metal.
In electro-therapeutics it is a bath of water with suitable electrodes and connections for treating patients with electricity.
Bath-stripping. A solution used for stripping or removing the metal plating from an object.
Batten. A strip of wood grooved longitudinally, in which electric light or power wires are set. The grooved strip is screwed to the wall, the wires being laid in the grooves, and then covered with a thin wooden strip fastened on with small nails.
Battery. A combination of parts, or elements, for the production of electrical action.
A number of cells connected parallel or in series for the generation of electricity. Under this heading there are at least one hundred different kinds. Nowadays the dynamo is the cheap and efficient generator of electricity.
Battery Cell, Elements of. The plates of zinc and carbon, or of zinc and copper, in a cell are called elements. The plate unattacked by the solution, such as the carbon or copper, is the negative element, while the one attacked and corroded by the electrolyte is the positive.
Battery, Dry. A form of open circuit cell in which the electrolyte is made practically solid, so that the cell may be placed in any position. A zinc cup is filled with the electrolyte and a carbon-rod placed in the middle, care being taken to avoid contact between cup and carbon at the bottom of the cell. The gelatinous chemical mass is then packed in closely about the carbon, so as to nearly fill the cup. A capping of asphaltum, wax, or other non-conducting and sealing material is placed over the electrolyte, and this hardens about the carbon and around the top inner edge of the zinc cup. The latter becomes the positive pole, the carbon the negative. Binding-posts, or connections, may be attached to the zinc and carbon to facilitate connections.
Battery, Galvanic. The old name for a voltaic battery.
Battery, Gravity. A battery in which the separation of fluids is obtained through their difference in specific gravity—for example, the bluestone cell. The sulphate of copper solution, being the more dense, goes to the bottom, while the zinc solution stays at the top. In its action the acid at the top corrodes the zinc, while at the bottom the solution is decomposed and deposits metallic copper on the thin copper plates.
Battery, Leclanché. An open circuit battery consisting of a jar, a porous cup, and the carbon and zinc elements, the electrolyte of which is a solution of ammonium chloride (sal-ammoniac). The carbon plate is placed in the porous cup, and packed in with a mixture of powdered manganese binoxide and graphite, to serve as a depolarizer. A half-saturated solution of sal-ammoniac is placed in the outer jar, and a rod of zinc suspended in it. Another form of the battery is to omit the porous cup and use twice the bulk of carbon, both elements being suspended in the one solution of sal-ammoniac; this form of battery is used for open-circuit work only, such as bells, buzzers, and annunciators. It is not adapted for lights, power, or plating purposes.
Battery Mud. A deposit of mud-like character which forms at the bottom of gravity batteries, and which consists of metallic copper precipitated by the zinc. It only occurs where wasteful action has taken place.
Battery of Dynamos. A term used in speaking of a number of dynamos coupled to supply the same circuit. They may be coupled in series or parallel.
Battery, Plunge. A battery in a cabinet or frame, so arranged that the active plates can be removed or raised out of the solutions. This is usually accomplished by having the plates attached to a movable frame which, by means of a ratchet-shaft and chains, can be raised or lowered. Its object is to prevent the corrosion of the plates when not in use.
Battery, Primary. A voltaic cell or battery generating electric energy by direct consumption of material. The ordinary voltaic cell, or galvanic battery, is a primary battery.
Battery, Secondary. A storage-battery, an accumulator.
Battery Solution. The active excitant liquid, or electrolyte, placed within a cell to corrode the positive element. Also called Electropoion.
Battery, Storage. A secondary battery; an accumulator; a battery which accumulates electricity generated by primary cells or a dynamo.
Battery-gauge. A galvanometer used for testing batteries and connections. It is usually small in size, and may be carried in a pocket.
Battery-jar. A glass, earthen, or lead vessel which contains the fluids and elements of each separate cell of a battery.
Baumé Hydrometer. (See [Hydrometer, Baumé].)
Becquerel Ray and Radiation. An invisible ray discovered by Becquerel, which is given out by some compounds and chemicals—notably uranium—and which has the power to penetrate many opaque bodies and objects impenetrable to the actinic rays of ordinary light. These rays are used chiefly in connection with the photographic dry-plate.
Bell, Electric. A bell rung by electricity. The current excites an electro-magnet, attracting or releasing an armature which is attached to a vibrating or pivoted arm, on the end of which the knocker is fastened.
Bichromate of Potash. A strong, yellowish-red chemical, used chiefly in battery fluids and electrolytes.
Bifilar Winding. The method followed in winding resistance-coils. To prevent them from creating fields of force, the wire is doubled and the looped end started in the coil. Since the current passes in opposite senses in the two lays of the winding, no field of force is produced.
Binding. Unattached wire wound round armature-coils to hold them in place.
Binding-post. An arrangement for receiving the loose ends of wires in an electric circuit and securing them, by means of screws, so that perfect contact will be the result.
Bi-polar. Possessing two poles.
Bi-telephone. A pair of telephones arranged with a curved connecting arm or spring so that they can be simultaneously applied to both ears.
Blasting, Electric. The ignition of a blasting charge of powder, dynamite, or other high explosive by an electric spark, or by the heating, to red or white heat, of a thin wire imbedded in the explosive.
Block System. A system of signalling on railroads. Signal-posts are arranged at stated spaces, and on these signals appear automatically, showing the location of trains to the engineers of trains in the rear.
Bluestone. A trade name for sulphate of copper in a crystallized state.
Bobbin. A spool of wood or other non-conducting substance wound with insulated wire. In a tangent galvanometer the bobbin becomes a ring with a channel to receive the wire.
Boiling. In secondary, or storage, batteries the escaping of hydrogen and oxygen gases, when the battery is fully charged, resembles water boiling.
Bonded Rails. Rails used in an electric traction system, and which are linked or connected together to form a perfect circuit. Used principally in the third-rail system.
Brake, Electro-magnetic. A brake to stop the wheels of a moving car. It consists of a shoe, or ring, which by magnetic force is drawn against a rotating wheel to stop its revolution.
Branch. A conductor which leads off from a main line to distribute current locally.
Brassing. A process of electro-depositing brass in a bath containing both copper and zinc. A plate of brass is used as an anode.
Brazing, Electric. A process in which the spelter is melted by electric current, so that the two parts are united as one.
Break. A point where an electric conductor is broken, as by a switch or a cut-out.
Bridge. A special bar of copper connecting the dynamos with the bus wire in electric lighting or power stations.
Bronzing. The deposition of bronze by electro-plating methods. The mixture is of copper and tin, and a cast bronze plate is used as an anode.
Brush. A term applied to the pieces of copper, carbon, or other conducting medium in dynamos and motors, that bear against the cylindrical surface of the commutators to collect or feed in the current.
Bug. Any fault or trouble in the connections or workings of an electrical apparatus. The term originated in quadruplex telegraphy, and probably had some connection with the Edison bug-killer that he invented when a boy.
Buoy, Electric. A buoy to indicate dangerous channels in harbors and to mark wrecks and reefs. It is provided with an electric light at night, and with a gong or an electric horn by day.
Burner, Electric. A gas-burner so arranged that the flame may be lighted by electricity operated by a push-button at some distance from the fixture, or, close at hand, by means of a chain or pull-string.
Burning. In a dynamo, the improper contact of brushes and commutator, whereby a spark is produced and an arc formed which generates heat and causes the metal parts to burn.
Bus-rod. A copper conductor used in power-plants to receive the current from the battery of dynamos. The distributing leads are connected to these rods.
Butt-joint. A joint made by bringing the ends of wires together so that the ends butt. They are then soldered or brazed.
Button, Electric. A form of switch that is operated by pushing a button mounted on a suitable base. Used principally for ringing bells, operating lights, etc.
Buzzer. An electric alarm, or call, produced by the rapid vibration of an armature acted upon by electro-magnetism. The sound is magnified by enclosing the mechanism in a resonant box.
An apparatus resembling an electric bell minus the bell and clapper. The buzzer is used in places where the loud ring of a bell would be a nuisance.