Wiring Accessories

Wiring Accessories Points : wiring accessories, switches, surface switch, singie-way switch, two-way switch, flush switch, pull switches or ceiling switches, grid switches, rotary switches, push button switches, iron clad water-tight, switches, knife switches, lamp holders, ceiling roses, socket outlet, main switches, iron clad double pole switch, iron clad triple pole switch, definition Under the heading of Lightening Accessories, come the switches, lamp holders, ceiling roses, socket outlets, plugs etc. Switches A switch is used to make or break the electric circuit. It should so operated that it must make the circuit firm. At the instant of breaking the switch it should break the current so that there is no formation of are between the switch blades and contact terminals. Formation of are burns or damages he switch contacts. Such an are is avoided usually by means of providing a spring to movable blade s’ as to have a quick action. Following are the various types of switches. Surface Switch These switches are mounted on the mounting blocks fixed over the surface of the wall, i.e.. such types of switches project out of the surface of the wall. These are of two types. SingIe-way Switch This switch is provided with a single pole to control one light point at a time. Two-way Switch These are used for wiring circuits which are to be controlled from two points independently such as stair wiring. Flush Switch These switches are fixed in flesh with the wall and do not project out. Such types are used where high quality performance and appearance are desired. Now-a-days in every new built house such types of switch are used. Sometimes these switches are called Piano type switches. All above written switches are made for 5A, 250 V and 15A 250 V. Pull Switches or Ceiling Switches These switches are fixed on the ceiling and all the alive parts are out of reach of the operator. These are operated with a single pull on the card for the on and off position. These switches are used in bath rooms where water heater are used. These are also used in bed-rooms. Grid Switches The grid switches are similar to tumbler switches, except that they are lighter and are portable type, so they are used for the portable machines such as hand drill, portable grinder, etc. They are manufactured either in single-way or in two-way pattern both for 5 and 15 amperes. Rotary Switches These switches are much different from the ordinary tumbler switches. These switches are used for hot plates voltage stabilizers, etc., where many tappings are taken. Push Button Switches These switches are used for bell circuits, refrigerator lighting circuit. Iron Clad Water-Tight Switches Such switches are of cast iron, have very robust construction and are used for outdoor lamp controls. Knife Switches The knife switch consists of blades hinged at one end and are arranged to go into forked terminals or jaws at the other end. These are available as single throw switches or double throw switches. These are used for electroplating work. Lamp Holders As the name shows, a lamp holder is used to hold the lamp required for lighting purposes.

These holders can be classified as:
(i) Bayonet cap lamp holders which can further be sub-divided into.
(a) Pendent holder-used for hanging lights upto 250 watts.
(b) Batton holder — used for wall fixed light upto 250 watts.
(c) Screwed holder which when used with a bracket is called as bracket holder-upto 250 watts lamp.
(d) Water-tight bracket.

(ii) Switched Bayonet cap lamp holders used for table lamps.

(iii) Screw lamp holders: These types of holders are used with screwed type, lamps upto 1000 watts 250 volts.

(iv) Fluorescent lamp holders: These are either bi-pin type or of baycnet cap type, but pin type holders are generally used. Ceiling Roses These are used to provide a tapping to the pendent lamp holders, fan or fluorescent tube through the flexible wire. These are of two types:
(i) Two — plate type
(ii) 3 — plate type Socket Outlet The socket outlets have all insulated base with moulded or socket base having 3-terminal sleeves, The two thin terminals sleeves are meant for making connection to the cable with the third terminal sleeve thicker in cross-section is used for earth connection. The cover is again moulded and has corresponding 3 holes. These are made for 5 amps, and 15 amps. Load. Plugs For taking power from socket outlets. 3 pin plugs an used. These are also made for 5 amps and 15 amps. Main Switches The main switches are used to control the whole supply for a house or office. These are of following types: Iron Clad Double Pole Switch Iron clad double pole main switch used for single phase supply control and is made for 15 amps., 30 amps., 60 amps., 100 amps., 250 volts. Iron Clad Triple Pole Switch Iron clad triple pole main switch used for 3-phase supply control and is made for 1.5 amps, 30 amp, 60 amps., 100 amps., 150 amps., 200 amps, and 500 volts 3-phase, 4-wire main switches are also available. On neutral fourth wire link is used.