FUSE A safety device that protects an electric circuit from becoming overloaded.
Fuse - is a type of over current protection device.
Its essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected.
Short circuit, overload or device failure is often the reason for excessive current
A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
MINIATURE CIRCUIT BREAKER (MCB) An automatic switch that stops the flow of electric current in a suddenly overloaded or otherwise abnormally stressed electric circuit
when excessive current develops, a circuit breaker opens to protect equipment .
These abnormal currents are usually the result of short circuits created by lightning, accidents, deterioration of equipment.
A protective device that opens a circuit upon sensing a current overload. Unlike a fuse, it can be reset.
MINIATURE CIRCUIT BREAKER (MCB)
Able to protect the wiring and the loads of electrical circuits .
MCB’s are a Thermal-Magnetic type circuit breaker .
Thermal part loads (motors, heaters, power supplies, etc.)
will be protected from short circuits by its magnetic parts.
These are manufactured for fault level of up to 10KA.
Only with operating current range of 0.5 to 63 Amps .
Available types are single, double and three pole version.
Mainly used for control voltage protection.
Type B devices are generally suitable for domestic applications. They may also be used in light commercial applications where switching surges are low or non-existent. Type C devices are the normal choice for commercial and industrial applications where fluorescent lighting, motors etc. are in use. Type D devices have more limited applications, normally in industrial use where high inrush currents may be expected. Examples include large battery charging systems, winding motors, transformers, X-ray machines and some types of discharge lighting. Type B devices are designed to trip at fault currents of 3-5 times rated current (In). For example a 10A device will trip at 30-50A. Type C devices are designed to trip at 5-10 times In (50-100A for a 10A device). Type D devices are designed to trip at 10-20 times In (100-200A for a 10A device). MCB TRIPPING
MOULDED CASE CIRCUIT BREAKER (MCCB) An automatic switch that stops the flow of electric current in a suddenly overloaded or otherwise abnormally stressed electric circuit for high SC production .
MCCB (Mould case circuit breakers)
MCCB’s are Moulded case Circuit breakers, with protection facilities of over current, earth fault.
They are manufactured for fault levels of 16KA to 50KA and operating current range of 25A to 630Amps .
They are used for application related with larger power flow requirement.
In machines it is used for main supply connection.
MOTOR PROTECTION CIRCUIT BREAKER (MPCB) An automatic switch that stops the flow of electric current in a suddenly overloaded or Short circuit protection.
MPCB (MOTOR PROTECTION CIRCUIT BREAKER)
Motor Protection Circuit Breakers may provide the following protective and control functions.
Lightweight, all-plastic connectors and metal-shell versions available.
CPC connectors are UL 94V-0 rated stabilized, heat resistant, self-extinguishing thermoplastic material .
Operating temperature range: -55° C - 105° C
Unique contact pattern for each position size helps prevent accidental mating with other position sizes
CABLES A device for connecting electrical devices together.
Conductor is a material which contains movable electric charges.
Of the metals commonly used for conductors, copper has a high conductivity. Silver is more conductive, but due to cost it is not practical in most cases. Aluminum has been used as a conductor in housing applications for cost reasons.
Electrical Wires are either solid or stranded Conductors. "Solid Conductors" are exactly that, one solid Wire. "Stranded Conductors" consist of a Wire made of a number of smaller Wire strands wrapped around each other.
The choice between solid or stranded depends on the need for flexibility in handling and working with the Wire. Smaller electrical Wire Sizes are generally made of solid Conductors; while Wires larger than Number 6 AWG are generally stranded.
Insulation separates conductors electrically and physically within a cable.
The jacket physically protects the internal components of a cable, improves the cable’s appearance and provides flame redundancy.
Protects from the environment
Drain Wire Metallic conductor frequently used in contact with foil-type signal-cable shielding to provide a low-resistance ground return at any point along the shield.
Twisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources; for instance, electromagnetic radiation from unshielded twisted pair (UTP) cables, and crosstalk between neighboring pairs.
AMERICAN WIRE GAUGE(AWG)
American wire gauge (AWG) is a standardized wire gauge system used predominantly in the United States and Canada for the diameters of round, solid, nonferrous, electrically conducting wire. The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity
SHRINK TUBING Shrink tubing - is a sleeve ordinarily made of nylon or polyolefin, which shrinks in diameter when heated.
Its diameter and thickness can vary. Heat shrink tubing is rated by its expansion ratio, a comparative of the differences in expansion and recovery rate .
Heat shrink is used to insulate wires offering abrasion resistance and environmental protection for stranded and solid wire conductors, connections, joints and terminals in electrical engineering .
To protect wires or small parts from minor abrasion, and to create cable entry seals .
Common shrink ratio is 2:1, while high-grade polyolefin heat shrink is available in 3:1
Heat shrink tubing is available in a variety of colors to allow easier color coding of wires and connections
Heat Shrink Tubing
Heat Shrink Tubing
SHIELDING Shielding - Contains electrical energy so that the signal on the cable does not radiate and interfere with signals in other nearby cables and circuitry.
It is the process of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive and/or magnetic materials .
Shielding is typically applied
1) to enclosures to isolate electrical devices from the 'outside world' and
2) to cables to isolate wires from the environment through which the cable runs
The cable shielding and its termination must provide a low-impedance path to ground. .
A shielded cable that is not grounded does not work effectively.
Make sure the equipment that the cable is connected is properly grounded.
• Protects the signal from external interference.
GROUNDING Ground or Earth may be the reference point in an electrical circuit from which other voltages are measured
In mains powered equipment, exposed metal parts are connected to ground to prevent contact with a dangerous voltage if electrical insulation fails .
An electrical ground system should have an appropriate current-carrying capability in order to serve as an adequate zero-voltage reference level .
Signal Ground is a reference point from which that
signal is measured.
Chassis ground is the box or frame in which
a circuit is built.
TERMINALS A device for joining electrical circuits together
A terminal is the point at which a conductor from an electrical component, device or network comes to an end and provides a point of connection to external circuits .
A screw terminal is a type of electrical connector where a wire is clamped down to metal by a screw .
BusBar/ShortBar A device used for Making Multi- Connection
In electrical power distribution, a busbar is a thick strip of copper or aluminum that conducts electricity within a switchboard, distribution board, substation or other electrical apparatus .
Busbars are used to carry very large currents, or to distribute current to multiple devices within switchgear or equipment.
Busbars are typically either flat strips or hollow tubes as these shapes allow heat to dissipate more efficiently due to their high surface area to cross-sectional area ratio.