Endurance test 5x Lemnis Pharox III

Posted by Marcel van der Steen in Endurance Test No Comments»

pharoxiii_end2009 Lemnis has had measured 5 lamps of Pharox III in endurance test. This article gives the results.

This lamp has been measured before it went into life test.

Summary measurement data

The columns in the following table contain the averaged results of the 5 lamps before and after the life test of 6000 hours (to be exact, after 6750 hours).

parameter initial after endurance test remarks
Color temperature 3028 K 3053 K No significant change
Illuminance Iv@25deg ambient temp 54.2 Cd 52.5 Cd Measurement values are all calculated to T_amb = 25 deg C (it appeared that the lamps showed a decrease of 1 % at 2 degrees increase).
Beam angle 196 deg 199 deg
Power P 5.86 W 5.76 W About 2 % decrease in the first part of the endurance test.
Power Factor 0.51 0.53
Luminous flux @ 25deg ambient temp. 380.4 lm 380.9 lm
Luminous efficacy 64.9 lm/W 66.2 lm/W
CRI_Ra 85.6 86.4
Coordinates chromaticity diagram x=0.4413 and y=0.4163 x=0.4359 and y=0.4085
Measurement report (PDF) olino-pdf

Test duration and test environment

The start was in Juan 2011 and the test lasted until Nov 2010.

During this time the lamps have seen the following temperatures and humidity.

Priode of 2010

The ambient temperature varied between 9 – 37 degres C and the relative humidity between 25 – 72 %.

Change of lamp parameters

In this chapter two graphs showing the change of parameters (illuminance and chromaticity coordinates).

The change of lamp parameters during the life time test (all are avrages of the 5 lamps).

See the explanation article on OliNo for more explanation about the test (setup).

There is little deviation and change.

Herewith the results of the single lamps separately.

The changes of parameters of each lamp separately.

An extrapolation done towards 70 % of the illuminance is done. The illuminance is taken as a reference for the luminous flux (given that the beam angle has not changes significantly during the lifetime).

Extrapolation of the averaged illuminance.

Iv is calculated to its value at T-amb of 25 deg C (the intensity decreases 1 % at 2 deg C increase). See the explanation article of the endurance test for more explanation and link towards a document explaining the background of the extrapolation.

The result is 80.000 hours before the 70 % level is reached.

Herewith the results of the single lamps separately.

The changes of parameters of each lamp separately.

There is some variation in the speed of decrease however all lamps have a significant lifetime.

Color variation

The variation in color point (chromaticity coordinates) is measured. Herewith the results of each lamp.

Change of color point of lamp 1.


Change of color points of lamps 2, 3, 4 and 5.

The color coordinates in the centre of the ellips are the points after 1000 hours of burning. All measurement points fall within the ellips that represents the 4 step McAdams ellips.

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