Cut-Out Panels Outlet-Boxes

Fuse-Boxes, Cut-Out Panels, etc.

From the very outset, the necessity was apparent of having a protective device in circuit with the conductor to protect it from overload, short circuits, etc. For this purpose, a fusible metal having a low melting point was em ployed. The form of this fuse has varied greatly. Fig. 54 shows a characteristic form of what is known as the link fuse with copper terminals, on which are stamped the ca pacity of the fuse.

The form of fuse used probably to a greater extent than any other, although it is now being superseded by other more modern forms, is that known as the Edison fuse-plug, shown in Fig. 55. A porcelain cut-out block used with the Edison fuse is shown in Fig. 56.

Within the last four or five years, a new form of fuse, known as the enclosed fuse, has been introduced and used to a considerable extent. A fuse of this type is shown in Fig. 57. Fig. 58 gives a sec tional view of this fuse, showing the porous filling surrounding the fuse-strips, and also the device for indicating when The fuse has blown. This form of fuse is made with various kinds of terminals; it can be used with spring clips in small sizes, and with a post screw contact in larger sizes. For ordinary low potentials this fuse is desirable for currents up to 25 amperes; but it is a debatable ques tion whether it is desirable to use an en closed fuse for heavier currents. Fig. 59 shows a cut-out box with Edison plug fuse-blocks used with knob and tube wiring. It will be seen that

there is no connection compartment in this fuse-box, as the circuits enter directly opposite the terminals with which they connect.

Fig. 60 shows a

cut-out panel adapted for enclosed fuses, and installed in a cab inet having a Con compart ment. As will be seen from the cut, the tablet itself is surrounded on the four sides by slate, which is secured in the corners by angle-irons. The outer box may be of wood lined with sheet iron, or it may be of iron. Fig. 61 shows a door and trim for a cabinet of this type. It will be seen that the door opens only on the center panel, and that the trim covers and conceals the connection compartment. The inner side of the door should be lined with slate, and the inner side of the trim should be lined with sheet iron. Fig. 62 shows a sectional view of the cabinet and panel. In this type of cabinet, the conduits may enter at any point, the wires being run to the proper con nectors in the connection compartment.

Figs. 63 and 64 illus trate a type of panel board and cabinet hav ing a push-button switch connected with each branch circuit and so arranged that the cut out panel itself may be enclosed by locked doors, and access to the switches may be obtained through two separate doors pro vided with latches only.

This type of panel was arranged and designed by the author of this instruction paper.