The test was attended by four Start floodlights (10, 20, 30 and 50 W) and four Gauss floodlights of the cheap Elementary series (also 10, 20, 30 and 50 W).
All spotlights are guaranteed for 2 years.
Gauss floodlights are significantly smaller and lighter (this is a disadvantage, since LED cooling can be worse, which can lead to a decrease in the service life).
All spotlights have an aluminum body. The front panel of Gauss is made of partially painted glass from the inside. Start at the front has a plastic frame with glass inside.
The ten-watt Gauss is quite "toy", the size of two matchboxes.
The 50-watt models do not differ much in size, but the difference in weight is significant.
30-watt models are close in size.
20-watt again is very different.
Spotlights Start (with the exception of the 10-watt model) are more expensive, the price of 10-watt is almost the same, the Start is even 10 rubles cheaper.
I tested the spotlights (of course, after a half-hour warm-up) and got the following results.
Spectra and results Start 50 W (left) and Gauss 50 W (right).
Unlike most bulbs, floodlights have everything honestly with power consumption (for all tested models it differs from the nominal by no more than 10%), with a power factor (it is really higher than 0.9 for all models, as stated), with light flow (for all models it was even higher than the declared one by 9-28%).
The spotlights of the two brands have different efficiencies, for Gauss it is 79-93 lm / W, and for Start it is 91-116 lm / W, so with the same power the Starts shine brighter.
On the packaging of the spotlights, the equivalent power of a traditional spotlight is indicated, and here the inconsistencies already begin. The start indicates a luminous flux of 2400 lm and the equivalent of 200 W for a 30-watt floodlight (this is close to reality), and Gauss writes 2100 lm and 300 W. Of course, 2100 lm this in no way can be 300 watts equivalent. And so with all models.
The color rendering index of all projectors is declared "more than 70", this is what it is (72-76). This is not enough for lighting living quarters, but it is acceptable for street lighting.
All Gauss Elementary floodlights have a very high level of light ripple (ripple rate 90-100%). This pulsation is clearly visible and can lead to eye fatigue, headaches and aggravation of nervous diseases.
Start also has pulsation, but less intense. The lowest ripple of light at the Start projector is 20 W (the measured ripple coefficient is 23%). Such pulsation is not visually distinguishable.
For projectors Start 30 and 50 W, the measured ripple coefficient is 35-36%. Such a ripple is barely visible visually, but will be clearly visible through the smartphone camera.
For 10W Start floodlights, the measured ripple coefficient was 53%. This ripple is clearly visible.
Another significant difference between Start and Gauss Elementary is the type of driver (internal electronics). Gauss has linear drivers. This leads to the fact that the brightness of the searchlight changes from the slightest changes in the voltage in the network and drops strongly at low voltage. When the mains voltage drops from 230 to 216-222V, the brightness drops by 5% of the nominal. At a voltage of 200V, the brightness drops by 20%, at 180V, the brightness drops by half.
The Start floodlights are based on IC drivers, so that they shine without changing the brightness with a significant change in the voltage in the network. The brightness of these floodlights begins to drop only when the supply voltage falls below 120 volts.
The Start floodlights work correctly with switches that have an indicator (do not light up or flash when such a switch is turned off).
Gauss floodlights do not work correctly with such switches (they glow dimly when the switch is off, and all the LEDs are on for the 10 W model, half of the LEDs for the 20-50 W models).
I measured the maximum temperature of the floodlight housings after a 30-minute warm-up. As expected, the smaller and lighter Gauss had temperatures 6-8 degrees higher.
Luminous flux, color temperature and color rendering index were measured using a 2-meter integrating sphere and an Instrument Systems CAS 140 CT spectrometer, power consumption and power factor (Power Factor) with a Robiton PM2 instrument, ripple coefficient with an Uprtek MK350D instrument. The minimum voltage level at which the luminous flux of the lamp decreased by no more than 5% of the nominal was measured using a Lamptest-1 device and a LATR Suntek TDGC2-0.5. The maximum case temperature was measured with a Seek Thermal thermal imager.
Is it worth it to save when buying spotlights, you decide. I would only recommend that you refrain from buying high-ripple floodlights, as well as floodlights with linear drivers.
© 2020, Alexey Nadezhin