OliNo

Lioris comes with a street lamp equipped with LEDs. In this article the 20 LEDs version is measured. The street light is so robust that the LEDs do not run hot. This will positively impact their lifetime. Also available are the measurement data in Eulumdat format. The measurements were done without the transparent cover of this street light.
Note from the producer: the used LEDs are of the 117 lm / W type!
See this overview for a comparison with other light bulbs.

Summary measurement data

parameter	meas. result	remark
Color temperature	5650 K	Bright white.
Luminous intensity Iv	348 Cd
Beam angle	141 deg	A wide beam. This is the average value. To different directions this light has a different beam (by design).
Power P	22.0 W
Power Factor	0.98	For every 1 kWh net power consumed, there has been 0.18 kVAhr for reactive power.
Luminous flux	1357 lm
Luminous efficacy	62 lm/W
CRI_Ra	71	Color Rendering Index.
Coordinates chromaticity diagram	x=0.3290 and y=0.3604
Fitting	230V	Needs connection to 230 V grid voltage.
L x B x H external dimensions	760 x 240 x 150 mm	Maximum dimensions
L x B dimensions of luminous area	350 x 195 mm	For this light the leds are situated in a bucket that reflects light. Herewith given are the dimensions of this bucket.
General remarks		The ambient temperature during the whole set of measurements was 21.0-24.5 deg C. Warm up effect: no effect. Voltage dependency: power and illuminance are dependent on the lamp voltage, in a linear way. For the Eulumdat file follow this link. Herewith a close up of the 117 lm LEDs.

Light diagram in Eulumdat format

This streetlamp is specifically designed to generate light at the needed spots underneath the lamp. Also to generate no light where this is not needed. The light pattern diagram in Eulumdat format show where the light is radiated to.

Light diagram giving the radiation pattern in the C0-C180 and the C90-C270 plane.

This diagram shows the intensity pattern for the planes C0-C180 and C90-C270, see also the photo for the indication of these planes. The unity is given in Cd/1000lm, meaning the luminous intensity in Cd when in the light there would be a total of 1000 lumen light output. Defining this value in Cd/1000 lumen makes it possible to compare lamps.

The C90-C270 plane the intensity is in a small beam downwards. Not straight downwards but somewhat oblique. In the picture to the left and in the diagram to the right.

In the C0-C180 plane there is a high intensity to the sides, around 55 degrees. This is especially good to illuminate a big part of the road in an equal manner.

In the angle area between 70 – 90 degrees there is almost no light emitted, which is good since it would not contribute to illumination on the road underneath the street light and it could lead to blinding the traffic when arriving from a distance and looking into the light of the streetlight.

Illuminance Ev at 1 m distance, or luminous intensity Iv

Herewith the plot of the averaged luminous intensity Iv as a function of the inclination angle with the light bulb.

The radiation pattern of the light bulb.

This radiation pattern shows a wide beam.

These averaged values are used (later) to compute the lumen output.

The intensity measurements (of each turn angle) as function of inclination angle.

This plot shows per inclination angle the intensity measurement results for each turn angle at that inclination angle. It is clear that for instance at 60 deg inclination angle, there is a high variability of the measured illuminance depending on the turn angle. This street light is specifically designed to do so; to produce light at those areas where it is needed.

When using the average values per inclination angle, the beam angle can be computed, being 141 degrees. However, this value is dependent from the plane observed. Especially for this street light, see the differences in radiation pattern for the two planes C0-C180 and C90-C270.; these differences are designed in.

Luminous flux

With the luminous intensity data as a function of the inclination angle, it is possible to compute the luminous flux.

The result of this computation for this lamp is a luminous flux of 1357 lm.

Luminous efficacy

The luminous flux being 1357 lm, and the power of the lightbulb being 22.0 W, yields a luminous efficacy of 62 lm/W.

A power factor of 0.98 means that for every 1 kWh net power consumed, a reactive component of 0.18 kVAr was needed.

Light bulb voltage	230 V
Light bulb current	97 mA
Power P	22.0 W
Apparent power S	22.4 VA
Power factor	0.98

Color Temperature and Spectral Power Distribution

The spectral power distribution of this lamp.

The measured color temperature is about 5650 K, and the light is bright white.

This measurement is done straight underneath the light bulb. This color temperature can also be measured when looking at the light bulb under different inclination angles.

The color temperature dependent from the inclination angle.

The dependency is different for different turn-angles. Generally there is an increase of the color temperature, up to 20 %.

Chromaticity diagram

The chromaticity space and the position of the lamp’s color coordinates in it.

The light coming from this lamp is at a distance to the Planckian Locus (the black path in the graph).

Its coordinates are x=0.3290 and y=0.3604.

Color Rendering Index (CRI) or also Ra

Herewith the image showing the CRI as well as how well different colors are represented. The higher the number, the better the resemblance with the color when a black body radiator would have been used (the sun, or an incandescent lamp).

Each color has an index Rx, and the first 8 indexes (R1 .. R8) are averaged to compute the Ra which is equivalent to the CRI.

CRI of the light of this lightbulb.

The value of 71 is lower than 80 which is considered a minimum value for indoor usage. Since this lightbulb’s color temperature is more than 5000 K, it is compared with the light of the sun or daylight.

Note: the chromaticity difference, that indicates the distance to the  Planckian Locus, is 0.008 which is higher than 0.0054, which means that the calculated CRI result is not meaningful.

Voltage dependency

The dependency of a number of lamp parameters on the lamp voltage is determined. For this, the lamp voltage has been varied and its effect on the following lamp parameters measured: illuminance E_v [lx], correlated color temperature CCT [K], the lamp power P [W] and the luminous efficacy [lm/W].

Lamp voltage dependencies of certain light bulb parameters, where the value at 230 V is taken as 100 %.

There is a dependency from the applied voltage. And the dependency there is, is also linear with applied lamp voltage. It indicates that the used power converter inside the lamp behaves in a stable manner.

To check whether this dependency can lead to visible changes in illuminance for possible grid voltage changes, just check what variations occur when the lamp voltage varies around 230 V + and – 5 V. Then the illuminance varies betwene + and – 4 % and will not be visible or noticeable.

Warm up effects

After switch on of a cold lamp, the effect of heating up of the lamp is measured on illuminance E_v [lx], correlated color temperature CCT [K], the lamp power P [W] and the luminous efficacy [lm/W].

Effect of warming up on different light bulb parameters; the 100 % level at the begin (top figure) and also at the end (bottom figure).

No mentionable effects due to the warming up.

Close up of the 117 lm LEDs

The efficient LEDs.