CONNECTIONS AND WIRING.
Fig. 20 shows how to connect up an automatic burner with two pushes;
thus one can be downstairs in the hall and the other upstairs,
allowing one to either extinguish or light the gas from either place.
The value of this arrangement is obvious; it allows one to light up
the hall before descending at night, or to put out the gas after one
is safely upstairs. Again, an automatic burner can be put in the
cellar and lighted and extinguished from the head of the
cellar-stairs, saving matches and danger of fire.
Fig. 21 shows the connections of one automatic burner and two pendant
or rachet burners. _P P_ are the pendent burners, _A_ the automatic
burner, _C_ the primary coil, _S_ the buttons which control the
automatic burner, _M M M_ the cells of battery, of which there
should be at least four, if not six. A low-resistance cell must be
used here, as before mentioned, one that gives not _less_ than 5
amperes on short circuit. It will be seen here that one side of the
battery is connected to ground (or gas pipe), the circuit being
completed owing to the burners being themselves screwed into the gas
pipe. Care must be taken, however, to first see that no insulating
bushings have been used at the gas fixtures, as is done in wiring for
electric light. In this case a double circuit will have to be run.
[Illustration: FIG. 20.]
[Illustration: FIG. 21.]
In wiring up an automatic burner with two electro-magnets, two wires
are run, one from the black button and one from the white button on
push-plate. Most burners have binding posts inside the case, the wires
running through a rubber-bushed hole in the base. One of the greatest
defects in the old style automatics arose from the two binding posts
being fixed on a hard rubber block, which was held by one screw to the
burner top. This screw got loose at times and the block used to twist,
making it hard to tighten the wires. But improvements have been made
in this direction, the later burners having a block with a projection
which engages in a hole in the cover, and is held by two screws.
If the push has been set in place, and all wiring done, connect up the
burner, first ascertaining to which binding post the two wires run.
This is done by having one button pressed, the lighting (white) one,
for example, and then touching the binding post with either wire. The
lighting armature will buzz violently when touched, whereas the
extinguishing one only strikes once when contact is made. When only
one person is working, a pin can be wedged in the push so as to keep
the circuit closed.
In setting up these burners care must be taken not to bend contacts or
alter adjustments, and absolute precaution is necessary that no wires
touch where uninsulated. A cause of trouble is a dirty burner which
does not allow the gas to strike the contact spark. The collar
carrying the second contact may shift, or perhaps become
short-circuited in a pendant or ratchet burner; a strip of asbestos
will remedy this.
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.
[Illustration: 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_.
[Illustration: FIG. 23.]
[Illustration: 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.
WIRING FINISHED HOUSES.
In wiring finished houses, especially wooden ones, the wires can be
run along skirting boards, and often pushed out of sight in the space
between the floor and the skirting. This is quite permissible, as the
wires, unlike electric-light wires, carry no dangerous current; but
waterproof wire becomes preferable, as the water used in washing a
floor will often creep under and rot the insulation. In going
upstairs, wires can often be run in the fluting of a moulding along
the stairway, and be quite inconspicuous; but wherever possible, fish
the wires up inside the wall. The main thing to be considered in
wiring is that the wires are large enough, well insulated, all joints
well made and taped and put where there is no danger of injury. Rats
have a habit of gnawing paraffin-coated insulation, and it is well to
run such in metal tubes. In joining or splicing wires, do it in a
thorough manner, and solder if possible. Never use the old bell-hanger
joint--the one in which the ends of the wires are merely looped
together. Strip insulation and scrape or sandpaper bright about three
inches of each wire to be spliced. Then, placing the bare wires across
each other about three-quarters of an inch from the insulation,
tightly wind the loose bare ends of each around the bare inside
portion of the one it is being spliced to. A touch of solder will
prevent trouble from oxidation, after the adhesive tape has been
wrapped on. Attention to details like these will often ensure the
satisfactory working of the job.
A handy tool for gas-lighting wiring is shown in Fig. 25. One end is
bored out to fit the small nuts on the ratchet and pendant burners,
and the other is filed flat for use as a screwdriver.
[Illustration: FIG. 25.]
A case may arise where there is electric light on the same chandelier
as the gas lights, and that an insulating bushing has been screwed in
between the fixture and the pipe. In this case it will be necessary to
run two wires to each burner, the pipe common return being now
unavailable. Another scheme is to interpose an insulating bushing
under each burner; then the second or return wire need only be run
from the burner to the gas pipe _outside_ the main bushing. But the
local fire-insurance rules must first be consulted.
Most ceiling gas fixtures will admit of the fixture wire being run
inside the brass shell, which makes a neater job. But the very best
of insulation must be used, and great care be taken that it be not
abraded. It should be shellacked or otherwise insulated before use.
The electric-light fixture wires are admirable for use here if there
is room.
For concealed work in a finished house, locate the position of the
fixture under the floor of the room above by measuring both in the
room where the fixture is and in the room above. Then cut out a piece
of the floor, drill up from underneath through the fixture
plaster-rose with a fine drill, and push the fixture wire up. The main
wire can be laid under the carpet, or along the floor-crack in the
upstairs room.
In wiring up wall-fixtures, push-buttons, etc., it is often possible
to fish the wire up from the floor by punching a hole at the fixture
and inserting a piece of chain (made for the purpose), attached to a
long and stout thread. Then drill into the skirting near the floor
plumb underneath the first hole and fish for the chain with a piece of
wire having a hook on the end of it. Where fixtures have brass
rosettes, these can be removed by (generally) unscrewing the fixture,
_but first shut off the gas_ at the meter, or plug the hole; this may
seem unnecessary advice, but experience warrants its being given. When
the chain is fished out, a piece of wire can be attached to the thread
and pulled through in turn. In most cases its point of exit at the
fixture can be concealed by the rosette, through a hole in which it
passes. Take care that the edges of this hole do not cut the
insulation. Care must be taken at every step in gas-lighting wiring.
In wiring up a push-button, screw all wires tightly under their
respective binding screws, and then cover wherever possible with
adhesive tape. As the wires must be somewhat loose to allow of the
connections being made at the back of the push-button at the wall,
they will have to be carefully pushed into the hole, and if they are
not tightly held by screws, trouble will result. It is a good plan,
when using fine enough wire, to make a sort of eye at the end of the
wire and pass the screw through this, instead of merely giving the
wire end a turn around the screw and then driving the screw home. Of
course washers should be used wherever an ordinary screw holds a bare
wire.
AUTOMATIC BURNER OPERATED BY DOOR.
One of the uses to which an automatic burner can be put is in
conjunction with an electric door-spring, lighting when the door is
opened, but preferably extinguished by independent push. In this case,
a form of trip spring should be used which would only make contact
during a portion of the travel of door. Such a trip is shown in Fig.
26.
_A_ is automatic burner; _C_, the primary coil; _B_, the battery; _T_,
a swinging trip piece of brass hinged in brass plate, _P_, which is
screwed over the door in such manner that the door opening in
direction of the arrow will cause the trip _T_ to strike against the
spring _S_, and make contact. This spring is insulated from the plate
_P_ by the hard rubber block _R_.
On the door being opened, the trip will make contact long enough to
light the burner and will then fall back as the door passes. On
shutting the door, the trip will be raised and will fall as the door
passes, but will not make contact. Or, if so desired, it can be made
to operate a second contact to extinguish the burner by fixing a
second insulated spring so it will be pressed when the top of trip
makes a downward movement--as when the door passes it in shutting.
[Illustration: FIG. 26.]
Various applications of automatic burners in connection with burglar
alarms will suggest themselves, but in these cases the utmost care
must be taken that the apparatus is in good working order; failure to
light might cause the room to be filled with gas, and serious results
ensue.
For those persons who use gas stoves and are mechanically inclined, an
arrangement of an alarm clock with an automatic burner will enable
them to light up without getting out of bed, or perhaps even waking
up.