Romisen RC-T5 4-Cree - notes on Shark driver upgrade

[wasBlinded]

I just received a second RC-T5 to modify for use as a bike light, and did some Lux and current draw comparisons with my first one that has been modified with the Shark/Remora boards.

Keep in mind that there may be differences in the Vf/efficiencies of the LEDs between the two that may account for some of the differences, but I suspect that to be minimal.

Basically, the two lower levels on the Shark/Remora modified light correspond very closely in output and current draw (from the power source) to High and Low on the original light. On low, the original drew about 240 mA for 2100 Lux and the modified drew 220 mA for 2300 Lux. With the original on high, it pulled 540 mA and gave 5100 Lux, while the modified on medium pulled 520 mA and gave 5400 Lux (all of these current measurements were with 7.90 volts measured at the head).

With the modified on High, it drew 1600 mA at 7.65 volts and delivered 11,500 Lux.

In summary, it appears that the Shark/Remora driver might be roughly 10% more efficient than the original driver board at comparable brightness levels. With the Shark/Remora on High, it is giving twice the brightness of the original on high, though at the cost of triple the current consumption.

I should add that the hotspot size of the modified light, for whatever reason, is visibly larger than the unmodified light. If the modified light were as tightly focused as the unmodified light, its Lux readings would probably be much higher and the differences in efficiency between the original driver board and the Shark/Remora board would be more dramatic.

 

[herulach]

I just received a second RC-T5 to modify for use as a bike light, and did some Lux and current draw comparisons with my first one that has been modified with the Shark/Remora boards.

Keep in mind that there may be differences in the Vf/efficiencies of the LEDs between the two that may account for some of the differences, but I suspect that to be minimal.

Basically, the two lower levels on the Shark/Remora modified light correspond very closely in output and current draw (from the power source) to High and Low on the original light. On low, the original drew about 240 mA for 2100 Lux and the modified drew 220 mA for 2300 Lux. With the original on high, it pulled 540 mA and gave 5100 Lux, while the modified on medium pulled 520 mA and gave 5400 Lux (all of these current measurements were with 7.90 volts measured at the head).

With the modified on High, it drew 1600 mA at 7.65 volts and delivered 11,500 Lux.

In summary, it appears that the Shark/Remora driver might be roughly 10% more efficient than the original driver board at comparable brightness levels. With the Shark/Remora on High, it is giving twice the brightness of the original on high, though at the cost of triple the current consumption.

I should add that the hotspot size of the modified light, for whatever reason, is visibly larger than the unmodified light. If the modified light were as tightly focused as the unmodified light, its Lux readings would probably be much higher and the differences in efficiency between the original driver board and the Shark/Remora board would be more dramatic.

Bit of a zombie post I know, but how do you find it as a bike light? How have you got it mounted? It looks pretty long, I'm looking for something a bit floodier than my current light, and this might be right o the money.

 

[wasBlinded]

I still haven't turned this thing into a bike light, still looking for the time to do it - other things have been taking priority.

Mounting will be somewhat problematic. I won't be using the full battery tube, since it will be wired to a water bottle battery, so that decreases the weight a bit, though it will make it even more unbalanced. I'll probably try the Twofish lockblock on this, but it might not be rigid enough. A couple of hose clamps would mount it securely, but sure would be ugly. I'm still keeping my eyes open for the perfect solution......