Burner Distribution.
In fitting a house with electric lighting burners, the question of selection is best solved as follows: For the main hall and foot of the cellar-stairs, use the automatic burner. For other hallways, dining-room, drawing-room, and bathroom use ratchet burners which turn on and light gas when chain is pulled. For bedrooms use plain pendant burners; automatics and ratchets add an element of danger, in that they may not turn off gas, or may leak. Most of this type on the market are as reliable as it is possible to make them, but still accidents will happen.
The frontispiece shows a diagram of the wiring in a dwelling house of medium size, dividing it into three sections, each section being controlled by a switch—either a hand switch or one of the automatic cut-out switches elsewhere described. The burners are distributed as follows:
No. 1 in the front cellar, pendant or ratchet.
No. 2 in the rear cellar at foot of stairway is an automatic burner controlled from kitchen above.
Nos. 3 and 4 ratchet burners on chandeliers in drawing-room and dining-room.
No. 5 ratchet or pendant in kitchen.
No. 6 pendant in bedroom.
No. 7 ratchet or pendant in bathroom.
No. 8 pendant in bedroom.
No. 9 pendant in bedroom.
Nos. 10, 11, and 12 pendants in bedroom.
No. 13 automatic burner in hallway operated from pushes in lower and in upper hallways.
The articles required for this job are as follows:
Two automatic burners.
Three gas lighting push-buttons and bases. Pendant and ratchet burners according to number of lights in rooms.
Six cells—open circuit battery.
One three-lever switch.
One 8 or 10 inch spark coil.
Three pounds No. 16 patent finish office wire.
Two ounces No. 24 gas-fixture wire.
One pound tinned 3/8" staples.
Few square inches tinfoil.
Small roll insulating tape.
Tools: 4-inch screwdriver, pocket knife, 4-1/2-inch side-cutting pliers, hammer, piece of sandpaper.
The simple section switch is shown enlarged in Fig. 22. The wires 1, 2, and 3 are from their respective circuits and terminate at the switch arms A A A. The wire from the battery B and coil C runs to each switch-stud S S S. If trouble shows on the line, each circuit can be thrown off by moving its switch arm until the fault is located. If it is not found at once, and the battery is weak, (test each cell with an ordinary electric bell), open all the circuits until the battery is recuperated, and disconnect the battery wire from the switch. Then attach the battery wire to the bell and touch each switch lever with a wire from the other binding post of the bell. If there is a short circuit on any section, the bell will ring or tremble when the arm is touched.
Fig. 22.
On the contrary, if the burners fail to work and no sign of a short circuit can be thus obtained, it is evident that a wire is broken or a screw is loose.
To locate a break, connect up the bell as just described and attach the testing wire to the switch with all levers closed; this is actually putting the bell in series with the battery, coil, and ground. Then hunt for the break. Take a long piece of wire and fasten one end to a ground pipe. Then touch the other end to the circuit wire in the cellar as far as you can go, baring the insulation in spots, but carefully re-insulating it again. If there is no break in the cellar, the bell will ring loudly at each contact. Next, proceed to the next floor and repeat the operation, gradually working away from the battery. As soon as you pass the break, the bell will fail to respond. Two persons here are better than one, as it may be necessary to go quite a distance from the bell before finding the trouble.
Fig. 23 shows details of the wiring from the hall light to the two push-buttons. A wire is run right down from the top push T, middle connection, past the lower push L, where a similar branch joins it, until it reaches the section switch. The lighting and extinguishing wires from the lower push run up and are joined on to the similar wires from the top push, which latter wires go directly through the floor and ceiling to the automatic burner A.
Fig. 23., & Fig. 24.
Fig. 24 is the detail of the wiring for the cellar automatic burner A, from the push P, and is so clearly shown as not to require further explanation.
The secret of success in gas-lighting work is careful wiring. The platinum tip of the vibrating rod is often bent, either by accidental blow or by the continual hammering against the tip on the collar. This often causes an open circuit when the lighting armature refuses to buzz. Again, soot will form, causing weak action owing to imperfect contact. Examine, adjust, and clean; here, as in all electrical work, contacts must be clean.
In general wiring, use weatherproof office wire, or, better still, well-made electric light wire. For ordinary house work No. 16 B. & S. gauge is preferable; smaller wire means higher resistance and less current at burner. For braided office wire, No. 16 runs about 95 feet to the pound, No. 18 about 135 feet to the pound. The cheaper grades of wire without the patent finish or extra insulation are not worth using; sooner or later trouble will ensue, and once a house is wired, it is no pleasant job to hunt trouble, especially if the wire was put on before the plaster. In modern buildings in large cities, the use of conduit tubes has become general, but the handling of these conduits comes more under the province of the electric-light wireman and less within the scope of these pages.
In wiring new wooden buildings do not draw wires too tight; the wood may expand and either break wire or cause a weakening of the insulation. In wiring before the plaster is put on, always leave a good length free, so it will not be covered up by the plasterers.
The wire used on the gas fixture is of a special kind, being made for the purpose. It is made in two sizes, No. 22 and No. 24 B. & S. gauge, and with three windings of cotton, three outer layers of cotton and one of silk, or three windings of cotton which is soaked in fireproof preparation, and then wound with silk.
As the piece used is generally short, these small sizes are sufficient in carrying capacity. After wiring up a fixture, this fine wire can be tied on to the pipes, etc., with thread, and a good coating or two of shellac varnish applied. When this is dry, the thread can be removed and the shellac will hold the wires on to the fixture. On no account finally connect up the battery to a circuit when shellacking the wire. Wait until the shellac is thoroughly dry and hard—at least half a day, if possible.
White lead is generally used at the joints where the burner screws into the fixture, but tinfoil wrapped round the joint will give good service. It prevents leaks and ensures a good contact.
The ground connection at the battery must be first-class; do not be content with just wrapping a few turns of wire around the pipe in the cellar (assuming the battery is in the cellar), but clean and scrape the pipe; clean at least two feet of the wire, wind it tightly and evenly on the pipe and solder it. There is a pipe-clamp made which is clamped on the pipe and the wire attached to that, but it must be properly put on a clean surface.