Starled Liggies. Sorry maar ek gaan die tegniese gedeelte in Ingels doen, ek ken nie al die Afrikaanse woorde nie, en ons Afrikaners is mos taal gekultiveerd (of geletterd en tweetalig - of hoe). Onthou net, julle het gevra vir die sales pitch ne' ;-)
Each light unit has three LED's, emitting a total of around 67 lumens at 350mA per LED. The three LED's are connected in series, and the max current is the same for each LED. The amount of light however is three times that of one LED. You thus get three LED's light for the power of one or >200lumens at still about 350mA.
When the design was considered, there were some discussion on the boat design forum about the noise radiation where a series of LED's were driven from a high stepped up voltage. Since inductors are used in these switch mode drivers, rf emissions are inevitable. So it happened that an overly eager person installed a host of these switch mode LED drivers, probably at some cost too, in his boat - and couldn't use some of his equipment when the lights were on. The emissions (harmonics) simply suppressed the signals. This means that a linear driver was the only option to avoid the possibility of this happening, and a (very) little bit of efficiency is lost in the power supply. Be a bugger if you experience GPS problems when using the light for instance...
The circuit uses a pic microprocessor that does the dimming which is set with a potentiometer (pot). When the light is dimmed the current is reduced with a pulse width modulation (PWM) method which is a standard method of dimming these devices. It simply means that 5% to 100% of the power is allowed to power the LED's. The PWM is done at 500Hz, further reducing the possibility of emissions.
Below a 5% pot setting the micro processor switches the LED power off and goes into a power saving mode. The total current consumption is reduced to ~0.1mA or about 100 micro amps. Above 5% setting on the pot, the pic wakes up and perform it's controlling the LED brightness according to the pot's adjustment. This means while the lights are connected to a battery and turned off, they will not drain the battery.
Dimming allows one to keep goggo's (bugs) out of the tent (that or they become less visible), also use less power, and on the boat you can avoid night blindness.
About the LED's -
The manufacturer claims the highest flux (most light for the drawed current) per family in the world (don't they all). These however are not too bad.
Chromaticity is in the 2500 to 3800 Kelvin temperature range, and is close to natural sunlight which makes it possible to read with this light without tiring the eyes, and colours can be distinguished properly ie if you read a map or book or have to work on colour coded wiring. The blue tint is absent from these LED's that is associated with some light emissive LED's, hence the natural colour quality. No UV light is emitted either. You can compare the emissive quality range in the planckian graph here
http://en.wikipedia.org/wiki/Chromaticity
These LED's also sport a lambertian radiation pattern, which means it emits light at an even brightness in all directions. You can see more here -
http://en.wikipedia.org/wiki/Lambertian_reflectance. It just means the light is evenly bright where it shines and there is no lighter or darker spots.
The expected lifespan of these LED's at 350mA continuous on, is a whopping 100 000 hours, or about 20 years. I'm not big on maintenance and I don't want to fix or replace parts ever. I know the big savers buy the R50 lights at macro every time they go fishing.
Since each light source is small, the LED junction is very bright and blinding to look at. The light enclosure is hence shaped to allow an angle of light, while reflecting the rest into the allowed angle that enhances the brightness. The light, when mounted in a horizontal position allows a person to approach without being blinded.
The lights were designed to be multi purpose. General purpose is for the campers, they use them in their tents or install them in their vehicles or use them at home when eskom doesn't work. They can be permanently fixed or portable. The price per LED light is R200 and excludes shipping.
A bit more special application is for use on boats or when you are going to use your's at the beach night fishing where there is a bigger chance of salt water getting into it. For these apps we conformal coat the electronics (it's a specially designed protection coating for waterproofing electronic circuitry) and the potentiometers are sealed with a dow corning or similar sealant, then conformal coated. Despite this precaution, it does not make the lights submersible, ok. It just makes them a lot more durable and resistant to the effects of salt water. It is a big job and tedious and a pain in the whatsename to conformal coat these LED lights. It also takes two days to cure enough to handle, so I'm ripping you off an extra R20 for the conformal coated ones.
There are polarity protection and some spike and over voltage protection on board. The lights I loaned you have a too low over voltage device in, it will kick at around 15 / 16 V already. It should be around double that, all the electronics can endure an over voltage spike of up to 40V - which is why Mev Spyker and Benny Nuwe Boot Boekwurm should return their lights so I can exchange them for the correct and new lights. The new lights also makes around 20 to 30% more light ok, so worth the postage, it is a notable improvement.
The power supply is any 12V battery. You can run it off your 12V automotive power, boat's 12V or use it portable with a sealed lead acid battery.
The lights will maintain brightness down to 10.5V below which the light will dim, and extinguish at around 8 or 9V. At 10,5V your battery is really flat, like a Toyota Land Cruiser's tyre in a sekelbos :-D He he... daai sekelbos brand darrem net so lekker in jou voet as wat die liggies brand ;-)
The light regulate it's brightness irrespective of if the power supply is 10.5V or more.
If you plug it into 230V mains or drive over it with the bakkie or get it into the boat's prop and it breaks the warranty is void. I have no problem replacing a problem unit but if you bugger it up, it becomes your problem. Any one not happy with what he receives can just return the light in it's original condition and I will refund him, no problem.
On the moment we are awaiting the enclosures before we can finish any. That's basically it.
Any questions - gooi !
