X LIGHTING AND ELECTRIC WORK

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Modern Developments

When we talk of lighting the modern home, there is generally but one idea that enters our minds—electric lighting. Even those dwellings remote from any power-house are installing small generators in preference to the oil or gas lighting systems.

The modern
50-watt bulb

Then, too, when we refer to good lighting we no longer think of glaring bulbs of light, exposing all the harsh glow of the white, hot filaments, causing one’s eyes to squint and strain to find things in the corners of the room; but we picture a room flooded with mellow illumination emitted from fixtures which shield the direct rays of light from our vision.

Another change that has come about in our conception of good illumination is the quantity and intensity of the light we expect from the incandescent bulb. It was only a few years ago that we marvelled at the yellow light given off by the 16-candle-power carbon-filament bulb. But to-day if a bulb gave off as feeble an attempt at lighting as did these old ones we would think it on its way to the graveyard of lightning-bugs. We cannot talk of 16-candle-power lamps when the glow of a modern Mazda light is around. We used to specify on the plans so many 16-candle-power lights for the dining-room or living-room fixtures, and it is hard to change our habits to refer to the modern 40 or 50 watt lamps which have taken their place in the home.

Thus within a period of not more than ten years our whole conception of illumination has been jolted out of a rut.

Indirect Lighting

Now we have reacted so far in the matter of protecting our eyes from a direct view of the source of light that some enthusiasts advocate a system of indirect illumination, concealing the lights so completely from the eyes that their location is difficult to know. This is carrying the problem too far beyond its rational limits. Such a system of indirect illumination reduces shadow to a minimum; consequently the forms and the beauty of objects in the room are flattened. Moreover, the eye unconsciously is confused at not being able to locate the source from which the illumination comes, and, being puzzled, the mind naturally resents it. For the small house, at least, the system of indirect illumination carried to this extreme is not at all suitable.

Fig 1

A type of fixture which develops a partial indirect illumination, and yet which allows a certain quantity of light to come through direct to the eyes, so that the source of light is easily discernible is the most satisfying and most suggestive of home comfort. Such a fixture is shown on page 122.

Common-Sense Solution Needed

Moreover, the lighting of a small house must be studied with common sense, and no rule of the thumb can be laid down. Certain enthusiastic illuminating engineers offer typical plans and suggestions for the wiring of houses, which plans are crowded so full of outlets that they look like a map of the starry heavens. We have in front of us now such a plan in which a small living-room is marked to contain four wall outlets containing two lights each, two more outlets on each side of the fireplace, a wall plug for attaching a portable lamp or two lights, and a central ceiling outlet for four lights. In addition to these is another base plug and floor plug. The room is about 14 by 17 feet, and if all lights were turned on at once and all base plugs attached to lamps there would be a possible grand total of twenty 50-watt lamps in this medium-sized room. Such brilliant illumination might please the jaded nerves of the tired business man, but his wife would never consent to such a garish display of wealth-eating current.

The problem of illumination for the small house can be sanely considered from five different angles: (1) General illumination; (2) local illumination; (3) ornamental illumination; (4) movable lamps; and (5) light control.

By general illumination is meant the lighting required to flood the room as a whole, and not locally in any one corner. The easiest and commonest method of doing this is to provide a central fixture, containing from two to four 50-watt lamps, or their equivalent, which are hidden in some commercial type of semi-indirect lighting fixture. The type of fixture shown on page 122 is one of the finest, and with a silk shade around it the warm, cheerful effect of a home is greatly enhanced by this method of lighting. When this fixture is hung in the dining-room or living-room a single 200-watt Mazda lamp is employed, while in the other rooms a single 100-watt lamp is used. In the kitchen no shade is necessary. Usually in laying out the electric outlets upon a plan the central dining-room and living-room lights are shown to carry four 50-watt lamps, and those in the other rooms, in the hall, and on the porch are marked to have two 50-watt lamps or their equivalent.

But it is not absolutely essential to have a central light for general illumination. Some architects prefer to have a certain number of wall lights controlled by one switch, and obtain a general glow with these lamps. By securing the right type of fixture which shields the raw filament of light from the eyes, this method of general illumination often produces a feeling of comfort and homelikeness unsurpassed by the other system.

In those rooms where work is done under the central light, such as the kitchen and pantry, and where opaque, indirect reflectors have been used throughout the rest of the house, it is essential to provide direct lighting-fixtures, so that the light can be thrown down upon the working plane. Translucent reflectors or prismatic reflectors are used, and a frosted bulb or a porcelain-tipped bulb is most suitable with this reflector.

Local illumination is intended to give greater intensity of light over certain portions of the room where work is carried on. Either a wall light or a special drop light, protected by a reflector, is used. Such lights are placed conveniently over the kitchen-sink and side table, over the laundry-tubs and ironing-board, over the coal-bin, near the boiler and over the work-bench in the cellar, by the side of the lavatory in the bathroom, over at the side of the dresser in the bedrooms, inside of closets and alongside of the serving-table in the dining-room. These local outlets are generally planned to carry two 50-watt lamps or their equivalent.

Types of Direct Lighting Reflectors

Other wall lights than these are usually introduced for ornamental purposes. The side lights for the fireplace in the living-room, or the panel lights on the wall, or the bracket lights for the bookcase cannot be considered more than ornamental features. Not more than one 50-watt lamp is planned for these outlets.

In addition to the general, local, and ornamental illumination are those portable lamps which have become more and more a serviceable and decorative feature of the home. The reading-lamp in the living-room, the light for the music on the piano, the table-lamp in the bedroom, and the candle-lamps on the dining-room table are the most used of this portable type. To properly attach these bulbs, a base-board outlet must be installed at a convenient place in the room, so that the electric cord to the light will not have to be too long nor pass across any part of the floor where it may trip up the feet of some absent-minded member of the family.

When the lighting of the small house has been considered from these angles, the control is then the essential problem. The incoming feeder, the meter, the house switch and service switch, and the distributing panel must be located conveniently in the cellar. Often the distributing panel with its fuses is placed on the first floor for convenience of replacing a burned out fuse when some line has been overcharged.

The next matter of control is the location of switches. All central outlets and general illumination should be controlled by a switch at the entrance-door to the room. The usual type of switch used is the so-called three-way switch.

The 3-way Switch to control
light at two places

The hall light should be controlled from up-stairs and from down-stairs. The porch lights and the front and rear door lights should be switched on and off either from the inside or outside of the house. One light in the cellar should be governed by a switch at the top of the cellar stairs. And this is about all the complication of control necessary.

Now, in addition to the lighting of a house, certain floor and base-board outlets must be provided for attaching various electrical devices that have become rather common. In every cellar there should be at least one special power-current outlet for any household machinery that might be installed. In the laundry there should be at least two special outlets to which a washing-machine, a mangle, electric drier, or an electric iron can be connected.

There should be at least one special outlet in the kitchen to which may be attached a motor for operating the coffee-grinder, egg-beater, ice-cream freezer, dish-washer, etc. Sometimes an electric refrigerator may be installed, in which case an outlet must be provided for this motor.

Sometimes a special outlet is installed in pantry for a dish-warmer or water-heater.

In the dining-room a floor outlet should be provided for operating on the table such things as a toaster, chafing-dish, coffee-percolator, egg-boiler, etc.

In the living-room a floor outlet will be found useful for such electric apparatus as would be carried on a tea-table or for running a home stereopticon.

In the bathroom and in the master’s bedroom a special outlet is useful to connect up such devices as vibrators, hair-driers, curling-irons, shaving-mugs, electric heaters, etc.

Base-board outlets of the ordinary type should be distributed throughout the house to provide convenient connections for vacuum cleaners and fans.

Most of these electric devices require not more than 600 watts. Electric irons, toasters, chafing-dishes, coffee-percolators, and other heating mechanisms use up to this maximum of watts, but motor-operated machines, like fans and ice-cream freezers, require about 100 watts.

As to the kind of wiring which the architect should specify, he has a limited choice. The knob-and-tube system is the cheapest, but not the safest. The flexible cable (BX) is better, although slightly more expensive. Rigid conduits or flexible steel conduits are not suited to the economic needs of the small house and are not used, except in special places. For example, an overhead feed wire may be brought in from the street at the level of the cornice, and then carried down to the cellar in a rigid conduit on the outside of the house.

Cleat

Knob Tube
Flexible Conduit (BX) Rigid Conduit

In addition to the wiring for lighting there must be an independent system for bell service. The current for such a system must be supplied by dry batteries when the local power company gives a service of direct current, but when it supplies an alternating current a transformer can be used and the bells operated upon this energy. In the kitchen there should be a magnet-operated annunciator, connected with the front and rear doors and the dining-room push-button.

In laying out the lighting plans for a small house the standard symbols shown here are used, but a key should always be given to their meaning upon some part of the sheet, for it must be appreciated that the contractor can easily forget.

As an aid to laying out the lighting system on the plans, the following checking list is suggested, since it is simple.

SMALL HOUSE
ELECTRICAL EQUIPMENT LIST

Unless specified to the contrary, it is usual to assume that wall outlets in the living-room are to be placed 5 feet 6 inches above the floor, in bedrooms 5 feet 4 inches, and in halls 6 feet 3 inches. The usual height at which switches are placed is 4 feet.

Thus, by using common sense and the phrase in the specifications, “All work shall meet the requirements of the National Electric Code,” and requiring the contractor to furnish a certificate of approval for the entire installation as issued by the Board of Fire Underwriters having jurisdiction in the community, the architect has a reasonable surety of securing a good and safe system of wiring and lighting.


                                                                                                                                                                                                                                                                                                           

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