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luminous flux maintenance factor, <of an electric light source>

lumen maintenance factor, <of an electric light source>

ratio of the luminous flux of an electric light source at a given time in its operational life to its initial luminous flux, the electric light source being operated under specified conditions

Note 1 to entry: In IEC standards, “lumen maintenance” is also commonly used with the same meaning.

Note 2 to entry: The luminous flux maintenance factor has unit one and is usually expressed in per cent.

Publication date: 2020-12
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