Hi, the low price (22.99:money_mouth_face: teased me and I bought this headlamp from Lightmalls.
The Solarstorm brand is nowhere writen on the lamp, and XP-Ls, coolwhite but unknown tint, are WAY OFF CENTER:
Silicone gaskets are not properly placed or wrong dimension?
and generally, there is the feel of low quality on this product
READINGS
My cheap DMM shows around 0.03 amps paracitic drain
and the rest modes, measured at input, are as following:
low
medium
high
strobe is activated after pressing for 3 secs power button and it drains energy as in high mode
INSIDE BUILD
The threads bolts are screwed into are factory missplaced and kind of destroyed
view of buck driver (8.4v)
leds are wired in parallel
Heatsinking is poor, using a thin alloy shelf for disspatching heat of 3 overdriven XPLs
xpls are mounted on ultrathin alloy mcpcbs
LED AMPS READINGS
low
medium
high
The readings equals low-0.3 amps per led, medium 1.5 amps per led, high 1.74 amps per led
Considering the heat dissipation, I believe the leds are over driven and the result is that the heatlamps gets uncomfortably hot, after a couple of minutes on high mode.
PWM is too low, as seen in the following video
CONCLUSION
Build quality is too poor, under-acceptable level. Design has flaws also and I belive this is not a genuine Solarstorm product. It might be sold to Lightmalls as b grade - defective product, and this might eb a reason it is sold in this low price.
Sorry for my anorthodox review, I am a father and my english is not the best:-)
Thanks for reading
It may not matter much for this review, but if you use a lower current scale (move the lead from A to mA) when reading parasitic current, the reading should be more accurate. This can be tricky because if you turn the light ON, you'll likely blow the fuse. I can't understand why the light should draw 0.03A in the OFF state.
Well, it’s a momentary driver, so something is always on. This driver appears to be using the QX9920 buck controller, who’s datasheet calls for a Zener diode and load resistor in configurations like this (eg input voltage is above 5.5v). The Zener and load resistors will constantly use up electricity as long as they are hooked up. And that’s where (most of) a constant load of around 30mA is probably coming from.
EDIT: Just because the datasheet shows to use a Zener doesn’t mean it’s a good idea in this case. IMO there are certainly better ways to power the QX9920 in this case.