Билет 1
1) An electrical connector, is an electro-mechanical device used to join electrical terminations and create an electrical circuit. Electrical connectors consist of plugs (male-ended) and jacks (female-ended). The connection may be temporary, as for portable equipment, require a tool for assembly and removal, or serve as a permanent electrical joint between two wires or devices. An adapter can be used to effectively bring together dissimilar connectors.
Hundreds of types of electrical connectors are manufactured for power, signal and control applications. Connectors may join two lengths of flexible copper wire or cable, or connect a wire or cable to an electrical terminal.
Electrical connectors are characterised by their pinout and physical construction, size, contact resistance, insulation between pins, ruggedness and resistance to vibration, resistance to entry of water or other contaminants, resistance to pressure, reliability, lifetime (number of connect/disconnect operations before failure), and ease of connecting and disconnecting.
Types of electrical connectors:
Blade connector is a single wire connection in which a blade is inserted into the blade’ holder.
Terminal block connector is used to connect individual electrical wires.
Post connector is a connector used to attach a single wire to a piece of equipment
Clamp connector uses a V-shaped ring to attach a connector to a cable.
Spade terminal is the same a ring terminal expect that the metal part doesn’t make a full ring.
Ring terminal is a single wire connection in which a screw or bolt is inserted to make electrical contact.
Plug and socket connector has one plug with prongs that is inserted into the openings of a receptor plug.
Solderless connector connect wires by using mechanical pressure instead of solder
Split bolt connector is used for taps and splices in building wiring.
Offset connector is used to change the direction of a wire entering an electrical box.
2)
Билет 2
1)
2)
Types of electrical connectors:
Blade connector is a single wire connection in which a blade is inserted into the blade’ holder.
Terminal block connector is used to connect individual electrical wires.
Post connector is a connector used to attach a single wire to a piece of equipment
Clamp connector uses a V-shaped ring to attach a connector to a cable.
Spade terminal is the same a ring terminal expect that the metal part doesn’t make a full ring.
Ring terminal is a single wire connection in which a screw or bolt is inserted to make electrical contact.
Plug and socket connector has one plug with prongs that is inserted into the openings of a receptor plug.
Solderless connector connect wires by using mechanical pressure instead of solder
Split bolt connector is used for taps and splices in building wiring.
Offset connector is used to change the direction of a wire entering an electrical box.
Insulation displacement connector allows for a wire to not be stripped before connecting.
Билет 3
1)
Landing gear is component of airpalne that support and provide mobility on land, or any surface , helps helps for landing or takeoff.The landing gear consist of wheels, struts, bracing, shock absorbers and others associated devices.There are nose wheel and tail wheels. Landing gear can be wheels, skis, or floats.
On the small aircraft undercarriage is always in a released state because they fly at low speed. Faster aircraft usually have retractable undercarriages, which fold away during flight to reduce air resistance or drag.
2)
Side cutters are type of pliers used for cutting, twisting or pulling wires.
Screwdriver is a tool used to tighten or loosen screws.
Long nose pliers are pliers with long blades able to grip or cut through wires.
Measuring tape is a tool with long piece of thin metal, paper or plastic with numbers on it.
Wire stripper is a tool used foe pulling the covering off wires.
Diagonal cutter are pliers that are only used for cutting wire and do not grip.
Utility knife is a tool with a thin, sharp slanted blade used to cut things.
Билет 4
1)
2)
A well-equipped set of tools is needed for us to do some kind of work at home or in the garage or somewhere else. Also, the toolset helps us not to lose our tools, so the tools do not deteriorate because they are stored in a dry place.
The basic set of tools should consist of:
Screwdriver set
Claw Hammer
Pliers
Adjustable Wrench
Tape Measure
Level
Utility Knife
Flashlight
Electric Drill
Hacksaw
Билет 5
1)
2)
Landing gear is component of airpalne that support and provide mobility on land, or any surface , helps helps for landing or takeoff.The landing gear consist of wheels, struts, bracing, shock absorbers and others associated devices.There are nose wheel and tail wheels. Landing gear can be wheels, skis, or floats.
On the small aircraft undercarriage is always in a released state because they fly at low speed. Faster aircraft usually have retractable undercarriages, which fold away during flight to reduce air resistance or drag.
Билет 6
3)Monocoque shell
In this method, the exterior surface of the fuselage is also the primary structure. A typical early form of this was built using molded plywood, where the layers of plywood are formed over a "plug" or within a mold. A later form of this structure uses fiberglass cloth impregnated with polyester or epoxy resin, instead of plywood, as the skin.
4)Semi-monocoque
Sectioned fuselage showing frames, stringers and skin all made of aluminium.
Materials
Early aircraft were constructed of wood frames covered in fabric.Then full fuselage of metal(heavy weight) then composite materials lower weight
2) The fuselage is an aircraft's main body section. It holds crew, passengers, and cargo.
Types of structures:
1)Truss structure
This type of structure is still in use in many lightweight aircraft using welded steel tube trusses.
2)Geodesic construction
In this type of construction multiple flat strip stringers are wound about the formers in opposite spiral directions, forming a basket-like appearance. This proved to be light, strong, and rigid and had the advantage of being made almost entirely of wood. . A fabric covering over the structure completed the aerodynamic shell.
Билет 7
What is a Fuse:
The fuse is an electronic device, which is used to protect circuits from over current, overload and make sure the protection of the circuit.
Fuse consists of a low resistance metallic wire enclosed in a non combustible material. Whenever a short circuit, over current or mismatched load connection occurs, then the thin wire inside the fuse melts because of the heat generated by the heavy current flowing through it. Therefore, it disconnects the power supply from the connected system.
Types :
Cartridge fuses
Cartridge fuses are used to protect electrical appliances such as motors air-conditions, refrigerator, pumps etc, where high voltage rating and currents required.
Blade Type fuses:
This type of fuses (also known as spade or plug-in fuses) comes in plastic body and two metal caps to fit in the socket. Mostly, they used in automobiles for wiring and short circuit protection.
Resettable Fuses:
Resettable fuse is a device, which can be used as multiple times without replacing it. They open the circuit, when an over current event occurs and after some specific time they connect the circuit again.
Билет 8
1)
More about Circuit Breakers
A circuit breaker is an automatic switch that is designed using electromechanical techniques to prevent power overload damage or short circuits. A circuit breaker has a solenoid inside, and it is kept at a certain voltage level, to keep the triggering mechanism in balance. Once a fault is observed in the circuit, such as an overload or a short circuit, the switch is triggered, and the current flow is discontinued. After solving the pertaining problem in the electrical system, the circuit breaker can be switched back to on again.
Like fuses, circuit breakers also come in many different sizes and packages, specialized to the requirements of the electrical system. They have current and a voltage rating indicating maximum allowable current and voltage.
2)
What is the difference between the Fuses and the Circuit Breakers?
• The fuse is a device working on the electrical and thermal properties of the conducting material, while a circuit breaker is a device working on the electromechanical principles.
• Once used a fuse has to be replaced but the circuit breaker can be reused after correction of the fault in the system.
• Fuses offer protection against only power overloads, while circuit breaker offers protection against power overloads and short circuits (voltage imbalances).
Билет 9
1) Types of receptacle boxes:
1) outlet box is a container that holds the plug in for electrical connections
2) pancake box is a thin round receptacle box
3) handy box is a metal box that is sometimes used as substitute receptacle box
4) integral nail box is a lower- priced receptacle box that already has nail holes
5) cut in box is a receptacle box that is used in a wall that has already been built.
Metal and Plastic Electrical Boxes(that holds wires)
Round Pan Electrical Box(Plastic box may used for outlet mounting)
Octagon and Round Electrical Box(May be used as a junction box, outlet or switch box)
Ceiling Fan-Rated Electrical Box (used for ceiling fan mounting, May be a round or octagon shape)
4-Inch Square Box (Commonly used as junction boxes with solid covers.
Square boxes may be installed in ceilings or walls for lighting fixtures, switches, or receptacles)
Electrical Box Covers (Covers are used to enclose an outlet box)
Box Extenders(Box extenders or extension rings are like boxes with no back; they are installed onto the front of standard electrical boxes to increase the box capacity)
2)
Билет 10
1)
2)
Билет 11
1)
2)
Timer switch that goes on and off at certain time
Билет 12
1)What is an Grounding System?
The connection between electrical appliances and devices with the earth plate or electrode through a thick wire of low resistance to provide safety is known as ‘Earthing’ or Grounding.
Earthing System or Grounding System in an electrical network work as a safety measure to protect human life as well as equipment, the main objective of the Earthing system is to provide an alternative path for dangerous currents to flow so that accidents due to electric shock and damage to the equipment can be avoided.
Metallic parts of equipment are grounded or connected to the earth and if the equipment insulation fails for any reason, then the high voltages that can be present in the equipment covering or outer box need some path to get discharged. If the equipment is not earthed, these dangerous voltages can be transferred to anyone who touches it resulting in an electric shock.