It is therefore decided to set discreet values, which practically cover the entire range of values. For a resistance manufacturer, it is not possible to match all such values. Nowadays Quantum Hall Effect is used as the ultimate standard of resistance, though this cannot be used so easily everywhere, except in laboratories.Įxact values of resistors will be calculated by individual designers will vary on a continuous range from zero to several thousand mega ohm values. Universal basic resistance standard has been kept in Europe against which standards all over the world are calibrated to create National Standards. These are also used to check accuracy of resistance meters all over by most manufacturers.

Standard resistors are extremely high accuracy resistors used as reference to calibrate or check the accuracy of other resistors in industry or establishments, on the production lines or equipment. If the closest value is not near enough, you can do it by connecting series-parallel configuration resistors. If you can't find the exact resistor value you've calculated for your circuit, then you need to select the next resistor value you've calculated.įor instance, if the measured value is 317.5Ω, then the closest standard value, which is 330Ω, is used. It is too difficult to find the exact value of the resistors you have measured for the project and circuits of electronics, etc., as here is an example of a situation such as 'how to calculate the resistor value for different LED circuits' or 'how to calculate the exact burnt resistor value and find the standard SMD resistor value.' Resistors usually come with regular values, such as E6, E12, E24, E48, E96, and E192. The resistor power ratings are not specified in the standard, so they often deviate from the series mentioned above. Standard resistor sizes, or the labeling of resistors with color codes or numerical codes, are an example. In addition to the preferred values, several other resistor-related requirements exist.

The resistors of various manufacturers are consistent with the same specification using standard values, which is favorable for the electrical engineer. This allows the manufacturer to limit the number of different values that must be produced or stored in stock. As resistors with different resistance values are manufactured by manufacturers, these end up roughly evenly spaced on a logarithmic scale.

Several significant uses serve to standardize resistor values.

Common resistor values