E24 preferred resistor values pdf

Resistors are available in a number of standard ranges, often called preferred values these ranges, or series, are set out by the electronic industries association eia, and are e3, e6, e12, e24, e48, e96 and e192. Often designs try to keep to the e3 or e6 standard resistor values, only using those in the e12, e24, e48 or e96 if absolutely necessary. The values are as follows and note there are 24 values per column or decade, hence e24. The resistor color code and the eia preferred values are internationally accepted standards, but some manufacturers have their own way of doing things. So far, we have calculated resistor values and then picked the nearest preferred value.

In this article youll find an interactive table in which you can find the standard resistor values, as used in electronics, and defined by the iec. Eia standard resistor values stackpole electronics, inc. Following this logic, the preferred values for 10% tolerance resistors between 100 and 1,000 ohms would be 100, 120, 150, 180, 220, 270, 330 and so on rounded appropriately. This specification may be changed at any time without prior notice. Apr 26, 2020 this process is followed through for all the values in a decade, creating a set of standard resistor values for each tolerance. For example, if resistors have a tolerance of 5%, a series of 24 values. These standard resistor values have a logarithmically based sequence and this enables the different values to be spaced in such a way that they relate to the component tolerance or accuracy. The e series of preferred resistor and capacitor values according to iec 60063 are reproduced in table 4. Chart tables of common or standard resistor values in the e3, e6, e12, e24, e48. Instead resistors are made in a restricted range of values and each value is quoted as a specific number of ohms plus or minus a percentage of the quoted value, this range of possible values is called the tolerance of the resistor. Successive values within a decade series are related approximately by a factor of for the e12 series, for the e24 series, for the e96 series and for the e192 series. Although it is theoretically possible to produce components of any value, in practice the need for inventory. In addition to the values of the e24 series as quoted, intermediate values, higher value of the e24 series.

There are four more or less commonly used resistor series, with 12, 24, 48, and 96 values per decade, respectively. Use of standard values is encouraged because stocking progr ams are designed around them. The number following the e specifies the number of logarithmic steps per decade. The number after the e denotes the number of values the series contains per decade. These values are the common resistor values that are used throughout the electronics industry. In addition to the values of the e24 series as quoted, intermediate. It is important to note that some values of the e24 series deviate from the mathematical rule. Standard series values in a decade for resistances and.

Using 10% tolerance devices as an example, suppose that the first preferred value is 100 ohms. Dec 20, 2016 depending on the accuracy required, resistances are available in 12 standard resistor values for every decade between 1 and 10, 10 and 100, 100 and etc. Commons category link is on wikidata commons category link is on wikidata using p retrieved from s. Finds the closest combination of two resistors from the e24 or e96 set of preferred values for a given resistance value. The bigger the value of a resistor the more it opposes the current flow. The eia e number is the number of logarithmic steps. The eia preferred values can be summarised in tabular form to give the different values within each decade. Each series denotes the number of different values in a decade. This calculator will select the closest standard resistor value, from 1% 5% or 10% standard eia values, calculates the error, and prints out a table of the standard values for the given tolerance. E24 series resistors color code, range and shorthand notation. The values of the e24 series are obtained by rounding the theoretical numbers of the geometric series with n24.

If you are a manufacturer of electronic components, and you want to list which resistors you sell in your catalogue, which ones do you write. A value of 105 ohm resistor falls within the 10% tolerance range of the 100 ohm resistor, so the next value outside the range. In 1952 the iec international electrotechnical commission decided to define the resistance and tolerance values into a norm, to ease the mass manufacturing of resistors. Aug 27, 2012 learn what preferred values for resistors are. The 120 ohm resistor has a value ranging between 110 and ohms. It makes little sense to produce a 105 ohm resistor since 105 ohms falls within the 10% tolerance range of the 100 ohm resistor. The eseries is another system of preferred numbers. It turns out that standard resistor values form a preferred number series defined by the eia 5% values are part of a standard called e24 the standard is based on a geometric series each value is approximately 1. Electronics assistant includes all these calculators and more in a standalone windows application. The electronic industries association eiaand other authorities, reiihe standard values for resistors, sometimes referred to as the preferred value system. Each resistor is packed with a card stating nominal resistance value at 100 v applied, selection tolerance, date and serial number. General note tt electronics reserves the right to make changes in product specification without notice or liability.

E24 series resistors color code, tolerance range and. Preferred resistor values available in the common resistor eseriese12, e24, e48, e96, e192 in an easy to read table. It consists of the e3, e6, e12, e24, e48, e96 and e192 series, where the number after the e designates the quantity of value steps in each series. May, 2012 an overview of how the e12 series is determined. The next reasonable value is 120 ohms because the 100 ohm resistor with a 10% tolerance is expected to have a value somewhere between 90 and 110 ohms. This process is followed through for all the values in a decade, creating a set of standard resistor values for each tolerance. It consists of the e1, e3, e6, e12, e24, e48, e96 and e192 series. The eia preferred values or standard resistor values can be summarised in a tabular form to give the different values within each decade. Because it is not possible to stock all possible values of resistances in a shop or component store, preferred values have been chosen to represent a usable spectrum of values for resistor color code and classes depending on the accuracy required, resistances are available in 12 standard resistor values for every decade between 1. Resistors and capacitors are available in a limited range of values, according to their manufacturing precision. Resistor color code calculator 3, 4 and 5 band resistors.

E96, e48, e24, e12, e6 and e3 series, the number indicating the quantity of values per decade in that series. Preferred component values are defined in british standard bs 24881. For example, many resistor manufacturers make every single value on the e24 list in 1% and 2% tolerance even though the practice makes little mathematical sense. For example, for e12 has twelve steps between any power. The most common preferred value series is the e24 series. Following this logic, the preferred values for 10% tolerance resistors between 100 and 1,000 ohms would be 100, 120. Jul 03, 2019 resistor e series the eia preferred values or standard resistor values can be summarised in a tabular form to give the different values within each decade. They are commonly available from component suppliers. Preferred number series for resistors and capacitors specifies the preferred values in the e24 series, which is the most often used. Preferred resistor values the eia e series specify the preferred values for various tolerances. Although it is theoretically possible to produce components of any value, in practice the need for inventory simplification has. Obviously, you dont know which ones the customers are going to want for their circuits. Generally, 5% tolerance resistors are available in e24 and. Preferred value series for resistors and capacitors.

Jan 12, 2009 it turns out that standard resistor values form a preferred number series defined by the eia 5% values are part of a standard called e24 the standard is based on a geometric series each value is approximately 1. Jun 06, 2017 if you are a manufacturer of electronic components, and you want to list which resistors you sell in your catalogue, which ones do you write. Download preferred resistor values lookup for free. These preferred values are derived from an exponential function, so they are known as e series e6, e12, e24 and e96, whose values are given in appendix a. Standard series values in a decade for resistances and capacitances e3 to e192 according to iec 60063 e192 e96 e48 e192 e96 e48 e192 e96 e48 e192 e96 e48 e24 e12 e6 e3 100 100 100 178 178 178 316 316 316 562 562 562 10 10 10 10 101 180 320 569 11 102 102 182 182 324 324 576 576 12 12 104 184 328 583. This table shows all possible values for the 4 most common e ranges on a range from 1 00 to. The first version of this iec 63 renamed into iec 60063 in 2007. Kitronik ltd how to calculate and understand resistor values resistors a resistor is a device that opposes the flow of electrical current. Youll find the values for the e6, e12, e24, e48, e96 and e192 series or preferred resistor values in this table. Standard eia decade values for e6, e12, e24, e96, e.

Following this logic, the preferred values for 10% tolerance resistors between 100 and 1,000 ohms would be 100, 120, 150, 180. The values of the e12 series are obtained by omitting every second term of the e24 series. Resistor values are organised into a set of different series of preferred values or standard resistor values. Current resistor technology enables very close tolerance levels to be achieved, yet there is still a great benefit in using resistors even from the e3 series. These are referred to as preferred values or eseries, and they are published in standard iec 60063. The following is a long list of all e24 series resistors from 0. The rationale is simple select values for components based on the tolerances with which they are able to be manufactured. Eia standard resistor values by tolerance% move the decimal point to achieve the actual value desired. The 4th band is always gold 5% tolerance for the e24 series. Ultrahigh value precision resistors ultrahigh value. The e24 series is for resistors with a 5% tolerance precision. To manufacture resistors of every possible value would be impractical. Resistor e series the eia preferred values or standard resistor values can be summarised in a tabular form to give the different values within each decade. This is where the resistor ratio calculator comes in handy.