I'm working on designing a lighting system to be used on a canoe in several long distance canoe races in the upcoming year (Texas Water Safari, Colorado River 100, etc.) From my research so far, this is what I have come up with:
Lights:
3x Cree XPG led's cool white @ 139 lumens ea. on star pcb
Driver:
BuckPlus 7023-D-E-1000 1000ma
Battery:
3000-4000mah LiPoly batteries @ 14.8v (one per night)
Lenses:
2x Ledil Heidi-XP 10x50
1x ??
Other:
Waterproof switches + resistors (on/off + dimming)
battery meter
The led's will be attached to a bracket/heatsink with thermal epoxy. They will be wired in series to the driver.
One of the switches would switch the power from the battery. The other would be connected with a resistor to the control wires of the driver.
What I'm not sure about is how the driver works. The datasheet says it is around 90% efficient at the voltage I am using. Does this hold true if the driver is dimmed via the external control? For example, if it is set to output half of its rated current (500ma), would the input current also reduce to half(assuming the output voltage remains constant)? My main reason for dimming is to run at lower power levels for longer battery life + the ability to have greater light output when necessary.
Also, does the driver need to be cooled?
Are there any recommendations for lenses for the XPG series? I like the idea of the asymmetric lenses (10x50) for two of the three lights, and I'm looking for a 30-40 degree for the third.
---------
Steve
Lights:
3x Cree XPG led's cool white @ 139 lumens ea. on star pcb
Driver:
BuckPlus 7023-D-E-1000 1000ma
Battery:
3000-4000mah LiPoly batteries @ 14.8v (one per night)
Lenses:
2x Ledil Heidi-XP 10x50
1x ??
Other:
Waterproof switches + resistors (on/off + dimming)
battery meter
The led's will be attached to a bracket/heatsink with thermal epoxy. They will be wired in series to the driver.
One of the switches would switch the power from the battery. The other would be connected with a resistor to the control wires of the driver.
What I'm not sure about is how the driver works. The datasheet says it is around 90% efficient at the voltage I am using. Does this hold true if the driver is dimmed via the external control? For example, if it is set to output half of its rated current (500ma), would the input current also reduce to half(assuming the output voltage remains constant)? My main reason for dimming is to run at lower power levels for longer battery life + the ability to have greater light output when necessary.
Also, does the driver need to be cooled?
Are there any recommendations for lenses for the XPG series? I like the idea of the asymmetric lenses (10x50) for two of the three lights, and I'm looking for a 30-40 degree for the third.
---------
Steve
