Ray_of_Light
Flashlight Enthusiast
I just bought the ITP EOS A4 flashlight.
It is incredibly small size for a 2x123 form factor flashlight, and a very good value for the price.
I checked here on CPF for a complete review of this light, but I haven't find any.
I did some current measurement at 6 Volt, it draws 10 mA at low level, 100 mA at medium level, and 500 mA at high level. The corresponding light output levels are close to those declared from ITP: 3 Lumens, 30 lumens, 160 lumens. As I have measued later, the low level is not regulated, it varies linearly with the input voltage.
No need to specify that levels are measured at the emitter at first turn on of the light. Optical and thermal losses not included...
The runtimes ( to 50%) I measured with two SF primaries are: 130 Hours (vs 250 Hrs declared) on low; 13 hrs on medium (vs. 12 hrs declared); 2hrs and 10 min (vs 2 hrs declared).
I measured the runtimes with the light standing in free air. I see many reviews on CPF being conducted with a cooling fan, but I don't agree with this methodology; many of the ligths, especially those using MC-E /P7 LEDs and an MCU, just stop working without cooling, and that doesn't reflect real life usage.
Then, I moved on to measure the current consumption of the ITP EOS A4 with a Li-Ion. I tried to fit an AW 17670 cell in the tube, but... it doesn't fit!
If there is any other fellow CPF member owning an ITP A4 and an AW17670, can you try to fit the battery in the light?
My AW17670 reads 16.7 millimeter diameter on my digital caliper, not including the peel-off label. The same caliper reads the bore of the A4 tube to be 16.85 mm.
Why ITP specified the A4 to be able to take 17670 if the tube diameter is smaller than 17 mm? It is just my light or also yours are of smaller diameter?
EDIT: I managed to measure the current consumption with a bench power supply.
On maximum brightness at 4 V, the ITP EOS A4 draws 0.95 Amp. Below 4 Volt, it looses regulation. At medium intensity, it draws 85 mA, at minimum intensity it draws 5 mA. This indicates that the low level is not regulated; as matter of fact, the brightness at minimum intensity at 4 V is noticeably lower. To confirm, at 8.4 V (2xRCR123) it draws 15 mA, and is brighter. The low level of the ITP EOS A4 is basically a resistored direct drive setup: this explains the extremely long tail of light after the batteries are depleted, and makes it a very good battery vampire.
Regards
Anthony
It is incredibly small size for a 2x123 form factor flashlight, and a very good value for the price.
I checked here on CPF for a complete review of this light, but I haven't find any.
I did some current measurement at 6 Volt, it draws 10 mA at low level, 100 mA at medium level, and 500 mA at high level. The corresponding light output levels are close to those declared from ITP: 3 Lumens, 30 lumens, 160 lumens. As I have measued later, the low level is not regulated, it varies linearly with the input voltage.
No need to specify that levels are measured at the emitter at first turn on of the light. Optical and thermal losses not included...
The runtimes ( to 50%) I measured with two SF primaries are: 130 Hours (vs 250 Hrs declared) on low; 13 hrs on medium (vs. 12 hrs declared); 2hrs and 10 min (vs 2 hrs declared).
I measured the runtimes with the light standing in free air. I see many reviews on CPF being conducted with a cooling fan, but I don't agree with this methodology; many of the ligths, especially those using MC-E /P7 LEDs and an MCU, just stop working without cooling, and that doesn't reflect real life usage.
Then, I moved on to measure the current consumption of the ITP EOS A4 with a Li-Ion. I tried to fit an AW 17670 cell in the tube, but... it doesn't fit!
If there is any other fellow CPF member owning an ITP A4 and an AW17670, can you try to fit the battery in the light?
My AW17670 reads 16.7 millimeter diameter on my digital caliper, not including the peel-off label. The same caliper reads the bore of the A4 tube to be 16.85 mm.
Why ITP specified the A4 to be able to take 17670 if the tube diameter is smaller than 17 mm? It is just my light or also yours are of smaller diameter?
EDIT: I managed to measure the current consumption with a bench power supply.
On maximum brightness at 4 V, the ITP EOS A4 draws 0.95 Amp. Below 4 Volt, it looses regulation. At medium intensity, it draws 85 mA, at minimum intensity it draws 5 mA. This indicates that the low level is not regulated; as matter of fact, the brightness at minimum intensity at 4 V is noticeably lower. To confirm, at 8.4 V (2xRCR123) it draws 15 mA, and is brighter. The low level of the ITP EOS A4 is basically a resistored direct drive setup: this explains the extremely long tail of light after the batteries are depleted, and makes it a very good battery vampire.
Regards
Anthony
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