Making Your Own LED Halogen Replacement

Although there are lots of cheap GU10 halogen replacement LED out there these days, and decent one too, but still very few that meet my requirement:

• As bright as 50W halogen (around 850 lumens), and;
• Although halogen has warm-white colour (3000K), I actually prefer daylight white (4000K), and;
• Beam angle 35 degree or wider, and;
• Under AU$25.

Those ones that are close to my requirement, so far, either:

• cost much more than AU$50, or;
• Not bright enough (see my rant in the next paragraph below), or;
• Have very narrow beam angle (less than 30 degree)
• Too bluish (around 6500K).

In term of brightness, lots of people on various website claim their LED halogen replacement have equal (or better) brightness with their 50W halogen counterparts. Well, a very narrow beam angle (like 15 degree or less), does make the centre illumination spot very bright. Indeed, brighter than 50W halogen, but it does NOT have more lumens (total light output). IF narrow beam angle is all you need, then these 3-watter LED with 15 degree beam angle or less are the perfect solution for you: cheap, bright, and very low power consumption.

But, until such thing exist (true 50W halogen replacement), I decided to make my own LED lighting. The new XM-L LED from CREE (well, with the current trend, it's soon to be replaced with newer and better LEDs still!) is the best candidate.

So, Components that are easily available to tinkerer like me:

1. Light bulb housing, including heatsink and optic for LEDs: SKU13741,
2. Constant current driver that can fit to the lightbulb housing: SKU14034,
3. LED module: SKU51989.

I have to make some compromises with components above:

• Not bright enough (from my calculation at the moment, it's only going to be 340 lumens),
• Optics still too narrow, but excluding them from the assembly should be good enough,
• Still too bluish with the available LED. I can get daylight white from other distributor, but they charge ridiculously expensive with over the top postage and handling on top of that.

I will report findings as soon as I finish my LED lightbulb!

Note: If you want MR16 halogen replacement, CREE has done the hard yard for you, check this out!

Memilih Lampu Bohlam LED

Mentang-mentang lampu LED sekarang makin nge-trend dan makin murah, jangan sembarangan milih. Tempoe doeloe, kalo milih lampu paling cuman liat Watt-nya aja, makin gede, ya makin terang. Gampang kan? Masalahnya, lampu LED lebih banyak neko-neko yang mesti dilihat:

1. Warna Lampu: Masalah warna baru keliatan kalo pasang banyak lampu deket2. Kalo lampu pijar (bohlam) biasa nggak usah pusing, mao bohlam merk apa juga warnanya sama. LED punya banyak warna, dari yang kuning kayak bohlam (warm white), sampe putih (cool white). Belom lagi tint: alias ke-ijo2-an atau ke-ungu2-an.
2. Efesiensi: bohlam biasa, mao merk apa juga, efisiensinya nggak jauh beda. 90-95% energi yang dipake jadi panas, bukannya cahaya. Maksudnya gini: lampu pijar 100W, cuman menghasilkan cahaya sekitar 1700 lumen, alias 17 lumen/Watt(*). Lampu LED, saat ini, efesiensinya bisa mulai dari cuman puluhan lumen/Watt, sampe 230 lumen/Watt (*). Lampu neon yang paling efesien aja cuman sekitar 100 lumen/Watt.
3. Sorot / omnidirectional: Lampu pijar sama neon biasanya omnidirectional (alias cahayanya nyebar kemana-mana). LED, dari sononya unidirectional (alias menyorot ke arah tertentu aja). Nah, di pasaran, jenis sorot-menyorotnya lebih banyak lagi (dari yang 15 derajat sampe 360 derajat), makanya konsumer mesti hati2 sebelom membeli.
4. Jenis colokan: Yang model sekrup ato colok. Nanti kalo nggak masuk gimana? Asal colok bahaya loh!

Contoh:

Perbandingan lampu halogen 50 Watt, LED 3 Watt, neon 9 Watt:

Perbandingan warna, terang dan pola sorot:

Foto kiri atas: Lampu halogen 50 watt (sorot, 60 derajat),

Foto kanan atas: Lampu neon warm-white 9 watt (sorot, 120 derajat),

Foto kiri bawah: Lampu LED warm-white 3 watt (omnidirectional),

Foto kanan bawah: Lampu LED cool-white 3 watt (sorot, 15 derajat).

Bisa diliat kan, tergantung aplikasinya, yang mana yang cocok? Masalah warna dan sudut sorot mesti dipikirken dulu sebelom beli lampu LED.

Di aplikasi lampu sorot sendiri, besar/kecilnya sorot juga mesti dilihat. Lampu halogen sorot biasanya punya sudut sorot 60 derajat (foto kiri atas). Jadi, beli lampu sorot LED juga mesti lihat sudut sorotnya, kalo nggak, bisa terlalu lebar, ato juga terlalu sempit, kayak foto kanan bawah di atas (sudut sorot 15 derajat).

Lampu Taman Sel Surya

OK, akhirnya project lampu surya anaknya pak jenggot bisa di finalised! Setelah coba rangkaian sana-sini dan bermacam masalah (lihat posting sebelumnya), si penulis akhirnya memutuskan pake off-the-shelf LED driver.

Dah, langsung to the point aja:

Setelah tes lapangan lagi, pake LED Driver ZXSC310, hasil tokcer! Selidik punya selidik, ternyata selama beberapa bulan, batre NiMH yang kejemur setiap hari jadi tekor. Alhasil, batre cuman bisa supply sekitar 1.1V di malam hari, kecuali malam yang dingin (dibawah 20C).

Nah, rangkaian baru diatas bisa beroperasi dengan efisien sampe batre 0.9V! Dapet darimana? Wah, ini tergantung situ tinggal dimana. Si penulis dapet dari RS Components: