IEC 60263-2020 pdf download.Scales and sizes for plotting frequency characteristics and polar diagrams
Echelles et dimensions des graphiques pour le trace des courbes de roponse en fréquence et des diagrammes polaires.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminotogical databases for use in standardization at the following addresses:
• ISO Online browsing platform: available at https:llwww.lso.org/obp
• IEC Electropedia: available at http://www.electropedia.orgl
aspect ratio
scale proportion between the y-axis and x-axis of a graph
Note 1 to entry: For graphs with a logarithmic frequency x-axis, the aspect ratio Is expressed as the y-aius factor per decade (in frequency), for example 25 dB)decade, or 1,25 decades!decade
3.2
decade
factor of 10 on a logarithmic scale
Note 1 to entry: For example, 500 Hz is I decaoe above 50 Hz. 0,01 is 3 aecaoes below .0 c,..
4 Characteristics plotted versus a logarithmic frequency scale
4.1 Decibel vs. log frequency plots
For graphs in which the y-axis depicts a level (in decibels) plotted versus logarithmic frequency on the x-axis. the aspect ratio shall be 10 dBldecade, 20 dB/decade, 25 dB/decade or 50 dB/decade.
4.2 Log quantities vs. log frequency plots
For graphs in which the y-axis depicts an absolute quantity or a percentage on a logarithmic amplitude scale plotted versus logarithmic frequency on the x-axis, the aspect ratio shall be 0,5 decades/decade, 1 decade/decade, 1,25 decades/decade or 2,5 decades/decade.
NOTE These aspect ratios correspond exactly to tite level equivalents of 10 dBldecade. 20 dB/decade. 25 dB/decade and 50 dBldecade Wi 41, respeclively.
5 Polar level diagrams
5.1 General
Polar level diagrams shall depict level as increasing outward versus radius. The angle of incidence shall be depicted as increasing moving counterclockwise relative to the reference direction. The angle assigned to the reference direction shall be 0. Major angular divisions shall be plotted as radii at a minimum of 30° intervals and shall be labelled.
5.2 Polar plots of absolute level
For a polar plot of absolute level referred to a reference quantity (e.g. dB re. 20Pa), the level range of the graph shall be 60 dB or 30 dB to the origin.
For polar plots of absolute level with a range of 60 dB to the origin, the maximum level shall be plotted less than 10 dB below the circle of maximum radius. Major level divisions shall be plotted as concentric circles with radii in multiples of 10 dB. Major divisions shall be labelled. Optional minor divisions are plotted as circles in 2 dB intervals without labels.
For polar plots of absolute level with a range of 30 dB to the origin, the maximum level shall be plotted less than 5 dB below the circle of maximum radius. Major level divisions shall be plotted as circles with radii In multiples of 5 dB. Major divisions shall be labelled. Optional minor divisions are plotted as circles in 1 dB intervals without labels.
5.3 Polar plots of relative level
For a polar plot of relative level, such as the difference between the absolute level from a transducer and the absolute level in a reference direction, the level range of the graph shall be 30 dB to the origin. The reference circle shall represent a relative level of 0 dB. The reference circle radius shall be 10 dB, 15 dB, or 20 dB or 25 dB. The maximum level shall be plotted less than or equal to 5 dB below the circle of maximum radius. Major level divisions shall be plotted as circles with radii in multiples of 5 dB. Major divisions shall be labelled. Optional minor divisions are plotted as circles in 1 dB intervals without labels.IEC 60263-2020 pdf download.