Work experience power point

Click here to load reader

  • date post

  • Category


  • view

  • download


Embed Size (px)

Transcript of Work experience power point

Slide 1

Work experience power pointResistor colour codingResistor combinationsElectronic components

One decade of theE12 series(there are twelve preferred values per decade of values) shown with their electronic color codes onresistors

A 100 k, 5% axial-lead resistor

A0 resistor, marked with a single black band

A 2260 ohm, 1% precision resistor with 5 color bands (E96 series), from top 2-2-6-1-1; the last two brown bands indicate the multiplier (x10), and the 1% tolerance. The larger gap before the tolerance band is somewhat difficult to distinguish.

To distinguish left from right there is a gap between the C and D bands.bandAis first significant figure of component value (left side)bandBis the second significant figure (Some precision resistors have a third significant figure, and thus five bands.)bandCis the decimal multiplierbandDif present, indicates tolerance of value in percent (no band means 20%)For example, a resistor with bands ofyellow, violet, red, and goldwill have first digit 4 (yellow in table below), second digit 7 (violet), followed by 2 (red) zeros: 4,700ohms. Gold signifies that the tolerance is 5%, so the real resistance could lie anywhere between 4,465 and 4,935 ohms.Resistors manufactured for military use may also include a fifth band which indicates component

ColorSignificantfiguresMultiplierToleranceTemp. Coefficient (ppm/K)Black0100250UBrown11011%F100SRed21022%G50ROrange310315PYellow4104(5%)25QGreen51050.5%D20ZBlue61060.25%C10ZViolet71070.1%B5MGray81080.05% (10%)A1KWhite9109Gold10-15%JSilver10-210%KNone20%M

The standard color code perEN 60062:2005 is as follows:

Resistors usepreferred numbersfor their specific values, which are determined by theirtolerance. These values repeat for every decade of magnitude: 6.8, 68, 680, and so forth. In theE24 seriesthe values are related by the 24th root of 10, whileE12 seriesare related by the 12th root of 10, andE6 seriesby the 6th root of 10. The tolerance of device values is arranged so that every value corresponds to a preferred number, within the required tolerance.

Zero ohm resistorsare made as lengths of wire wrapped in a resistor-shaped body which can be substituted for another resistor value in automatic insertion equipment. They are marked with a single black band.[4]The 'body-end-dot' or 'body-tip-spot' system was used for radial-lead (and other cylindrical) composition resistors sometimes still found in very old equipment; the first band was given by the body color, the second band by the color of the end of the resistor, and the multiplier by a dot or band around the middle of the resistor. The other end of the resistor was colored gold or silver to give the tolerance, otherwise it was 20%.[5]

Resistor in Series and Parallel Combinations

Resistor circuits that combine series and parallel resistors networks together are generally known as Resistor Combinationor mixed resistor circuits. The method of calculating the circuits equivalent resistance is the same as that for any individual series or parallel circuit and hopefully we now know that resistors in series carry exactly the same current and that resistors in parallel have exactly the same voltage across them.

Electronic components

Various electronic components

Anelectronic componentis any basicdiscrete deviceor physical entity in an electronic system used to affectelectronsor their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused withelectrical elements, which are conceptual abstractions representing idealized electronic components.

Electronic components have two or more electricalterminals(orleads) aside fromantennaswhich may only have one terminal. These leads connect, usuallysolderedto aprinted circuit board, to create anelectronic circuit(adiscrete circuit) with a particular function (for example anamplifier,radio receiver, oroscillator). Basic electronic components may be packaged discretely, as arrays or networks of like components, or integrated inside of packages such assemiconductorintegrated circuits,hybrid integrated circuits, orthick filmdevices. The following list of electronic components focuses on the discrete version of these components, treating such packages as components in their own right.

ClassificationA component may be classified aspassive, active, or electromechanic. The strict physics definition treats passive components as ones that cannot supply energy themselves, whereas abatterywould be seen as an active component since it truly acts as a source of energy.

However,electronic engineerswho performcircuit analysisuse a more restrictive definition ofpassivity. When only concerned with the energy ofsignals, it is convenient to ignore the so-calledDCcircuit and pretend that the power supplying components such astransistorsorintegrated circuitsis absent (as if each such component had its own battery built in), though it may in reality be supplied by the DC circuit. Then, the analysis only concerns the AC circuit, an abstraction that ignores DC voltages and currents (and the power associated with them) present in the real-life circuit. This fiction, for instance, lets us view an oscillator as "producing energy" even though in reality the oscillator consumes even more energy from a DC power supply, which we have chosen to ignore. Under that restriction, we define the terms as used incircuit analysisas:

Active componentsrely on a source of energy (usually from the DC circuit, which we have chosen to ignore) and usually can inject power into a circuit, though this is not part of the definition.[1]Active components include amplifying components such astransistors, triodevacuum tubes(valves), andtunnel diodes.

Passive componentscan't introduce net energy into the circuit. They also can't rely on a source of power, except for what is available from the (AC) circuit they are connected to. As a consequence they can't amplify (increase the power of a signal), although they may increase a voltage or current (such as is done by a transformer or resonant circuit). Passive components include two-terminal components such as resistors, capacitors, inductors, and transformers.

Electromechanical componentscan carry out electrical operations by using moving parts or by using electrical connections