Ray_of_Light
Flashlight Enthusiast
I just received the SureFire U2. I have measured the following current consuption and runtimes at 6 Volt:
Lev.1 35 mA (40 hrs.)
Lev.2 70 mA (20 hrs.)
Lev.3 135 mA (10 hrs.)
Lev.4 265 mA (5 hrs.)
Lev.5 570 mA (2 hrs.)
Lev.6 1380 mA (1 hrs.)
With the Pila 168A (3.7 V 1800 mA) I measured:
Lev.1 50 mA (36 hrs.)
Lev.2 90 mA (20 hrs.)
Lev.3 180 mA (10 hrs.)
Lev.4 370 mA (5 hrs.)
Lev.5 825 mA (2 hrs.)
Lev.6 1400 mA (1.2 hrs.)
There is to note that at level 6, with the Pila Li-Ion, the brightness is lower of the same level at 6 Volt, as is also evident from the current draw. Very likely, 3.7 Volts are not enough to keep the full regulation at level 6. May be it also depends on the binning of the LED.
The intensity adjustment ring has no detents but two stop positions at Level 1 and Level 6. It is not stiff, but it will NOT rotate by itself if the light is carried in the pocket, or in a bag.
The LOTC Clickie is working perfectly, unlike some models of Z57 that I have seen.
The bezel down clip is esteatically very pleasant, and it has its own functionality. I would never trust that clip to carry the U2 permanently on my belt, since it would release too easily. The two-prongs clip makes a very good lanyard attachment, by using a double knot.
A note on the O-rings. I was accustomed to the pretty beefy o-rings of the Z2, the M2, the L6. The U2 has skinnier o-rings then previous SF lights.
The bore diameter is so that the U2 can accomodate the Pila 168A, but only from the top (bezel side). There is a reinforcement steel insert at the bottom of the battery tube, that prevents the larger-diameter 168A battery to be inserted from the buttom. By removing the insert is possible to insert the 168A from the bottom. The insert is press-fitted in the tube, and I am not able to remove it.
The tint of LED varies from level 1 to 6. I had no possibilities to open the head and conduct some live measurement across the LED, but hooking a photocell to the oscilloscope indicates a DC drive of the LED, thus conforming the tint shift.
The beam is the same of the L5, with a little void in the center, as expected. In my U2, it is more visible at the lower levels.
The body of U2 reach about 65 Celsius after one hour at max. brightness, lower than the L4 or the L2, I think because of the higher mass of the light.
Anthony
Lev.1 35 mA (40 hrs.)
Lev.2 70 mA (20 hrs.)
Lev.3 135 mA (10 hrs.)
Lev.4 265 mA (5 hrs.)
Lev.5 570 mA (2 hrs.)
Lev.6 1380 mA (1 hrs.)
With the Pila 168A (3.7 V 1800 mA) I measured:
Lev.1 50 mA (36 hrs.)
Lev.2 90 mA (20 hrs.)
Lev.3 180 mA (10 hrs.)
Lev.4 370 mA (5 hrs.)
Lev.5 825 mA (2 hrs.)
Lev.6 1400 mA (1.2 hrs.)
There is to note that at level 6, with the Pila Li-Ion, the brightness is lower of the same level at 6 Volt, as is also evident from the current draw. Very likely, 3.7 Volts are not enough to keep the full regulation at level 6. May be it also depends on the binning of the LED.
The intensity adjustment ring has no detents but two stop positions at Level 1 and Level 6. It is not stiff, but it will NOT rotate by itself if the light is carried in the pocket, or in a bag.
The LOTC Clickie is working perfectly, unlike some models of Z57 that I have seen.
The bezel down clip is esteatically very pleasant, and it has its own functionality. I would never trust that clip to carry the U2 permanently on my belt, since it would release too easily. The two-prongs clip makes a very good lanyard attachment, by using a double knot.
A note on the O-rings. I was accustomed to the pretty beefy o-rings of the Z2, the M2, the L6. The U2 has skinnier o-rings then previous SF lights.
The bore diameter is so that the U2 can accomodate the Pila 168A, but only from the top (bezel side). There is a reinforcement steel insert at the bottom of the battery tube, that prevents the larger-diameter 168A battery to be inserted from the buttom. By removing the insert is possible to insert the 168A from the bottom. The insert is press-fitted in the tube, and I am not able to remove it.
The tint of LED varies from level 1 to 6. I had no possibilities to open the head and conduct some live measurement across the LED, but hooking a photocell to the oscilloscope indicates a DC drive of the LED, thus conforming the tint shift.
The beam is the same of the L5, with a little void in the center, as expected. In my U2, it is more visible at the lower levels.
The body of U2 reach about 65 Celsius after one hour at max. brightness, lower than the L4 or the L2, I think because of the higher mass of the light.
Anthony
