Lantern cree xm l. XM-L T6 LEDs

Waterproof hand lamp on CREE XM-L2 viki710 writing in July 3, 2015

Super Bright 100M Underwater 1800 Lumens CREE XML T6 LED Diving Flashlight/Torch - Black - $20.31
The product was received in the online store chinabuye.com for a review for free.


For several years, quite a lot of different Chinese lanterns have been flashed through my hands - large and small, manual, head and camping. Ordering this flashlight is a consequence of my desire to have a universal flashlight for most occasions. To do this, it was necessary that the lantern:

- was water resistant enough to withstand heavy rain and being dropped into the water,
- conveniently turned on with the thumb,
- wasn't very big
- Worked on 18650 cells.

The selected flashlight model is widely available on various trading platforms, but everywhere it is positioned as a noneme. On the other hand, it is clear that it has some kind of brand prototype, but I could not determine which one.

As for the characteristics of the flashlight according to the information of the store:

Light flow: 1800 lumens,
Light-emitting diode: CREE XM-L T6,
Case material: aluminum,
Certificates: CE,FCC
Operating modes: High/Middle/Low,
Water resistance: up to 100 meters.

The flashlight came in a standard OEM store packaging - a cardboard box with a bubble wrap. Spartan delivery set - the lantern itself and a lanyard to it.


Lantern length - 15 cm.


Weight - 209 g.


Turning on the flashlight is done with a slider, not a button. In this case, the brightness of the LED depends on the position of the slider.


The slider is magnetic. This allows you to adjust the brightness without touching the contacts directly. The freedom of the slider is limited by a metal retaining ring.


Adjustment with the slider on the one hand is convenient, as it allows you to smoothly adjust the brightness, but on the other hand, due to the small size of the handle, the slider is under the thumb, and you can accidentally turn on the flashlight. The problem would be solved by fixing the slider in the off position, but unfortunately, it is not provided.

Feels like the lantern seemed even a little small to me. If you keep your thumb on the switch, then the palm is longer than the handle - and this is with my not very large hand.


Structurally, the lantern consists of three main parts - the head, the handle and the back, which are assembled using threaded connections. For water tightness, each connection is shielded with two silicone rings.


The flashlight is powered by a single 18650 battery.

It is wiser to change batteries by unscrewing the back. To make it convenient, it has special grooves. Inside - as expected, a negative contact in the form of a brass spring.


Lantern head. The lens is glass.


Between the retaining ring and the lens is an additional silicone ring for water resistance.


In the description of the store, the flashlight LED is declared as CREE XM-L T6. But the CREE XM-L T6 LED does not look like this (see picture). In the offers of similar lights on the trading floors, there is a mention that the LED is CREE XM-L2.

Visually, CREE XM-L2 differs from CREE XM-L T6 in the presence of two legs instead of three and a key on the board (shown by arrows). It also looks like the LED of this lamp. Thus, the flashlight is still on the CREE XM-L2 LED. The description is inaccurate.


In accordance with the CREE XM-L2 specification, it produces 1052 lumens at maximum power (10W), which means that the claimed luminous flux for this flashlight of 1800 lumens is too high.

Lantern lanyard has a rubber insert and is quite long - 30 cm.


This design allows you to conveniently mount the flashlight on your hand.

Lantern testing

The lantern gives a rather diffused light. In principle, this is not surprising, because it is positioned as an underwater one. And under water, the range is not particularly useful.

Below is a beamshot at maximum brightness. Light spot diameter - 190 cm. Distance from the wall - 120 cm.


Changing the brightness of the lantern with the slider, in my opinion, is best illustrated with a video:

As for the range - here is a photo at night under conditions of diffused city lighting:


As you can see, the reflector setting also allows you to shine quite far into the distance.

And finally, the waterproof test. I don’t dive, so I don’t plan to swim with a flashlight, but situations are different, and no one is safe from falling into the water. As you can see from the photo, everything is in order with the waterproofness of the flashlight.

conclusions

In my opinion, the lamp is quite successful. Among the advantages, I would note the following:

- small lamp size
- Conveniently located thumb switch
- stepless brightness adjustment,
- diffused light allows you to illuminate a large area in front of you,
- high water resistance.

Of the shortcomings - the switch slider is not fixed in the off position. Those. so as not to inadvertently turn on the flashlight, you need to follow the slider. There are also some inaccuracies in the declared characteristics of the lantern, but the Chinese constantly sin with this, and they are not critical.

Recently in the lead, powerful Cree XLamp XP series LEDs are gradually losing ground, giving way to more advanced copies of the XM-L and XM-L2 series. The new chips have surpassed another brightness milestone, and Cree's first and second generation XM-L LEDs have quickly been adopted by leading lighting manufacturers. Despite the fact that the first generation of XM-L LEDs was released back in 2011, the chip turned out to be so successful that it still remains in demand. The most famous representative of the XM-L family of the first generation was the T6 LED group. With high performance, XM-L T6 emitting diodes are an excellent solution for designing lighting products.

Main characteristics

The XM-L LED crystal has a size of 5x5 mm and is visually larger than its predecessor from the XP family. Its distinguishing feature is the green backing. This family of light emitting diodes has a high light output with a typical thermal resistance of 2.5°C/W. With an operating current consumption of 700 mA, the nominal voltage drop is 2.9V. The 3.02mm hemispherical lens provides a 125° beam angle.

Luminous flux parameters

The most important parameter of any light emitting diode is the luminous flux. Cree has measured the actual minimum lumen output of the XM-L at 700 mA and an ambient temperature of 25°C. Also, for reference, the calculated values ​​\u200b\u200bare given at a current of 1000, 1500 and 2000 mA.

Heating the LED crystal inevitably leads to a decrease in brightness. For example, heating up to 75°C leads to a decrease in brightness by 10%.

Cree ranks lumen output by group and . There are currently 9 groups in the XM-L series. Crystals of the S4 group (164 lm) have the smallest flux of light, and U2 crystals (300 lm) have the largest. The most common are the LEDs of the T6 group, which have a minimum luminous flux of 280 lumens at a current of 700 mA. LED XM-L T6 have proven themselves both in the organization of artificial lighting of large commercial facilities, and in the design of hand-held flashlights. They are produced in cool and neutral white color in the range of color temperatures from 5000 to 8300°K.

T6 color bins and delivery kits

The LED bin is an indivisible region on the CIE-1931 chromaticity diagram. The need to introduce the concept of "bin" arose due to the fact that with the help of color temperature (TCV) it is impossible to perform an accurate gradation of light sources. The need for a more discrete approach to dividing white LEDs has led to the emergence of a new ANSI C78.377A color standard. The standard provides for 8 bins of Tcv with indication of permissible deviations in the entire space of white light on the CIE-1931 chromaticity diagram.
The difference in color between the ANSI C78.377A bin areas is easily noticeable, so large light emitting diode manufacturers additionally divide each area into several parts.

Cree has its own version of color standardization based on the ANSI C78.377A standard. Ordering LEDs from Cree with only a specific bin is not possible due to the small size of the bins and technological difficulties in mass production. The developer supplies the XM-L LEDs in kits, each of which includes several bins. You can recognize the bins included in the set by two characters at the end of the set code.

There are 6 delivery sets for LED XM-L T6: 50, 51, 53, E1, E2 and E3. The E3 kit additionally indicates the neutral tone of the LEDs, the rest indicate cool shades.





For example, an E1 package might contain 4 bins. In other words, if E1 is specified in the kit code, then the tone of the LEDs included in it will correspond to only 4 bins (1A, 1B, 1C, 1D).

Hello, friends! Today we will talk about bicycle accessories, because the season can already be considered open. The most important of these are the means that increase traffic safety. The most important thing is the bike helmet. It is advised to purchase it in offline stores, with fitting at the place. The second in a row will be bicycle lighting. A headlight/lantern and a taillight are mandatory for safe driving in the city and even more so outside the city. Just buying them over the hill is a nice thing, in our stores they are sold at a 2-3 times extra charge.
I accidentally stumbled on a headlight already with 5 XM-L-T6 LEDs, and I became very curious to feel it. I contacted Sunny from DX and after just a huge amount of time (thanks to our native mail) I received it for testing.

Here she is, beauty. I want to immediately draw your attention to the fact that there are no batteries or a charger in the package. The input voltage according to the passport is 5.4 ~ 12 V, I had batteries for ~ 8.4 V, 2S2P from the usual 18650, and we will test with them.

We climb inside, for this we need to unscrew the "crown". A sealing phosphorescent ring is laid between the glass and the crown. On the body itself there is a groove with a rubber ring. There is no silicone lubricant. Chip, field-effect transistor driver, sawn-off marking. It may well be that this is not a driver, but an opamp for adjacent SMD LEDs. By the way, they report the level of the supplied voltage and will tell you about the impending death of the battery.

An inductance is hidden on the reverse side, under it is a field switch, and its small strapping. The driver board is labeled YYTD84-05

The LED board is glued to the aluminum base with hot glue. Additional clamping is carried out through the diode pads themselves by a reflector; for this, gaskets are made of white plastic. The reflector is attached to the base with 2 screws. The big-eyed have already realized that the Chinese are cunning, calling this headlight XM-L-T6. In line with this is the XM-L2, which is the next step in the evolution of the XM series. This is evidenced by the presence of two wires inside the assembly and dotted perforation of the substrate. These diodes are more efficient than the previous generation, but which BIN- is not clear.

We solder into the power wire, measure the current at maximum mode. In this case, the voltage on the battery is 8.1 V, we get about 12 watts. Let's say 1 W will settle on the converter, which means 10-11 W go into the light. It immediately follows that the diodes do not operate at full power. But this is very cool. The LED efficiency curve is such that as the current flowing through it increases, its luminosity increases, but not as much as we would like. But at the same time, heating increases significantly and, as a result, its efficiency decreases. So, from the point of view of simplicity of design and common sense, it is better to put a series of diodes and power them at half power than fry them at full power and try to cool them somehow.
To complete the picture, in the middle mode, the current is 0.3 A. For the old headlight, a link to which will be later, these values ​​​​are 1.3, 0.8 and 0.4 A

The batteries are charged, you can start the combat comparison.

We will compare the headlights with which my wife and I ride at night. Charging and battery are used from them.

From the bike and tripod to the wall of the building is about 40 meters. The camera was in manual mode and at the same settings throughout the frames.

1)T6 XML-T6, maximum mode.

2)T6 XML-T6, medium mode.

3)T6 XML-T6, weak mode. In all modes, a noticeable bright middle, and a slight side illumination. Damn, I used to think that this is a great side illumination. But then you will understand how wrong I was.

4) 5 x Cree XM-L T6 3000lm max mode. This is a pancake chic side illumination!!! 111. I was shocked when I turned it on for the first time. The beam is wide, flooding, a real flood light!

5) 5 x Cree XM-L T6 3000lm, medium mode. The next mode is useless to shoot, it's a very annoying strobe. An excellent mode for driving during the day, motorists fire it from afar.

This is what the path looks like from the point of view of a cyclist.

Photos in the entourage.

It's time to sum up. Farah liked it a lot. Liked it so much, just like the first time I switched from a 100500 LED flashlight to one with a 3 watt LED. More than comfortable. The only thing is that this thing will blind oncoming pedestrians and motorists, so it should be tilted lower and, if necessary, immediately turned off. Get used to the fact that drivers will wink at a distance.

Of the frank minuses is that there is no charger and batteries in the kit. For those who buy as an upgrade, great, no need to pay for what is already there. And for those who buy from scratch, I would advise you to buy everything in the collection.

With the initiative of me, the first post -))