Re: [MBZ] OT: 12v lighting
rumor has it that Jim wrote: The LM317 is an active regulator, it's not a simple resistor, so it'll figure out exactly how much voltage to drop. It's not an ideal device, so it wouldn't even work right unless it gets to drop some voltage. (Look up its minimum required headroom.) As I recall, the LM317 must drop at least 1.5V, so while not a great device for battery operated devices, I think it's a reasonable choice for this project. It's also sturdy and self-protecting. If the supply voltage gets too high and the regulator is trying to dump too much heat, it will drop the output voltage till the current draw decreases enough that it's again safe. As long as the voltages stay with the correct polarity, those regulators are tought to kill. I haven't gone back to look at all the posts, but if the LM317 is set up as a _current_ regulator, then the LED should always be happy. --Philip
Re: [MBZ] OT: 12v lighting
On Tue, 10 Apr 2007 09:19:44 -0700 Jim Cathey [EMAIL PROTECTED] wrote: How much power am I really wasting at the resistor or LM317? I want to come in under 5w, how much do I plan for at the resistor? Given that you aim to run the LED's at a specified current, you can get awfully close just by using Ohm's law, in this case P-I^2R. For the LM317, also you lose 1.5I in it as well. Actually, he wants P=IE, where I is the current drawn by the LED and E is the voltage across the LED (for power dissipated in the LED) or the voltage across the LM317 (for the power dissipated in the LM317). The internal bias current of the LM317 will be insignificant compared with the current of the LED. That said, the LM317 is performing like an electronic resistor. If you have 1 amp flowing though the LED and 3 volts across it, the power dissipated in the LED will be 3 watts. If you're running it from 12 volts, the voltage across the LM317 or resistor will be 9 volts. The 1 amp current will cause it to dissipate 9 watts. The total power draw from the battery will be 12 watts, implying the efficiency to light the LED is 3/12 = 25% (rather low). There are a lot of switchmode regulators used to light up strings of LEDs. I've seen several advertisements at http://www.electronicproducts.com/, but don't recall any specifically at the moment. Coincidentally, their featured product today is, 85-lumen LED-based MR16 lamp replaces incandescents http://www.electronicproducts.com/ShowPage.asp?SECTION=PRIMID=FileName=hlap01.jun2007.html It has a 4 watt emitter and takes 12 volts AC/DC at 0.7 amps (8.4 watts, which implies an efficiency of 48%). Craig
Re: [MBZ] OT: 12v lighting
Jim Cathey wrote: If you're dead set on LEDs... look into anything that uses Luxeon LEDs... I've played with a 3W one... was VERY bright. The datasheet says they output 70-80 lumens. You'd need a 12V to 3V supply though. They look fairly persnickety about what you feed them. Best to be careful, I think they run them right on the ragged edge of death. I bought one just to tinker with... dumped 3V and 1A into it (current controlled benchtop supply), and it didn't complain. Couldn't look near it either... Could always use it at 50% rated power... ;-) John
Re: [MBZ] OT: 12v lighting
Jim Cathey wrote: If you're dead set on LEDs... look into anything that uses Luxeon LEDs... I've played with a 3W one... was VERY bright. The datasheet says they output 70-80 lumens. You'd need a 12V to 3V supply though. They look fairly persnickety about what you feed them. Best to be careful, I think they run them right on the ragged edge of death. They do run right on the edge, that is why a constant current (not constant voltage) pwm supply is required. Might be interesting to see what the input voltage limit is on the typical Luxeon Star setup. Heatsinking is important too.
Re: [MBZ] OT: 12v lighting
So I spent some time looking at different solutions yesterday and discovered that otherpower.com has instructions for making LED lights. Then I found I could buy the LEDs themselves on eBay very inexpensively. So right now it looks like I'll build my own light. For like $20 you get 50 (yes fifty) LEDs. Then I head over to Radioshack to get some breadboard and parts to build a powersupply. I'll wire up the LEDs in groups of 3 and then figure how many groups of 3 I need to get the light output I want. Right now I'm thinking 3 groups of 3 but we'll see how it goes. Then later down the road if I decide I don't like the color temperature its easy peasy to add a couple different color bulbs and get it just right... -Curt Date: Mon, 09 Apr 2007 15:58:31 -0500 From: John Robbins [EMAIL PROTECTED] Subject: Re: [MBZ] OT: 12v lighting To: Mercedes Discussion List mercedes@okiebenz.com Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=ISO-8859-1; format=flowed Curt Raymond wrote: I think perhaps you're a bit behind on the current LED technology. I'm looking at http://store.sundancesolar.com/12v18ledbufo.html Its only 40 lumens but that seems to compare well, I found a chart with a 15w CF that produces 105 lumens. This will only be a reading lamp, I've been using a small battery powered flourescent lamp for awhile. Its okay but not great, not focused enough really. Just to throw in my $.02 I'd look into CCFL lights that are typically used for case mods, etc. White ones do exist, but are harder to come by than the colored ones. No idea on wattage or anything though... I think they are certainly bright enough at least (or would be with a simple reflector for half of it). If you're dead set on LEDs... look into anything that uses Luxeon LEDs... I've played with a 3W one... was VERY bright. The datasheet says they output 70-80 lumens. You'd need a 12V to 3V supply though. http://www.luxeon.com/products/line.cfm?lineId=2 They have brighter ones too... G'luck with it! Little projects like these are great fun :-) John - 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. From [EMAIL PROTECTED] Tue Apr 10 13:14:49 2007 Received: from web32805.mail.mud.yahoo.com ([68.142.206.35]) by server8.arterytc8.net with smtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1HbGBN-0003s0-2C for mercedes@okiebenz.com; Tue, 10 Apr 2007 13:14:49 + Received: (qmail 40924 invoked by uid 60001); 10 Apr 2007 13:14:44 - X-YMail-OSG: LrKrhasVM1k0NFV__AaePgquU.blVFenJIAMuR8HmoutZ4FcpJkl6XXc9DIpbZ.Lk6hjzn_oqbKqWBNlxKGCq03pmdUEv1.45qPfThisaqGz7GC78Yok3OtjqoJ_Ng-- Received: from [198.51.119.130] by web32805.mail.mud.yahoo.com via HTTP; Tue, 10 Apr 2007 06:14:44 PDT Date: Tue, 10 Apr 2007 06:14:44 -0700 (PDT) From: Curt Raymond [EMAIL PROTECTED] To: Diesel List mercedes@okiebenz.com MIME-Version: 1.0 Message-ID: [EMAIL PROTECTED] X-Antivirus-Scanner: Clean mail though you should still use an Antivirus Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Content-Filtered-By: Mailman/MimeDel 2.1.9.cp2 Subject: Re: [MBZ] OT: 12v lighting X-BeenThere: mercedes@okiebenz.com X-Mailman-Version: 2.1.9.cp2 Precedence: list Reply-To: Mercedes Discussion List mercedes@okiebenz.com List-Id: Mercedes Discussion List mercedes_okiebenz.com.okiebenz.com List-Unsubscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] List-Archive: http://okiebenz.com/pipermail/mercedes_okiebenz.com List-Post: mailto:mercedes@okiebenz.com List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] X-List-Received-Date: Tue, 10 Apr 2007 13:14:49 - Oh and again I'm stuck on LEDs for 2 reasons: 1. They're neat B. They'll last a long long time and don't react badly to cold temps. CF bulbs in a rustic camp setting in the middle of the winter are not such a great thing... -Curt - Finding fabulous fares is fun. Let Yahoo! FareChase search your favorite travel sites to find flight and hotel bargains. From [EMAIL PROTECTED] Tue Apr 10 13:20:58 2007 Received: from wr-out-0506.google.com ([64.233.184.225]) by server8.arterytc8.net with esmtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1HbGHK-00047z-1c for mercedes@okiebenz.com; Tue, 10 Apr 2007 13:20:58 + Received: by wr-out-0506.google.com with SMTP id i22so1098092wra for mercedes@okiebenz.com; Tue, 10 Apr 2007 06:20:53 -0700 (PDT) Received: by 10.114.183.1 with SMTP id g1mr2793263waf.1176211252308; Tue, 10 Apr 2007 06:20:52 -0700 (PDT) Received: by 10.114.58.4 with HTTP; Tue, 10 Apr 2007 06:20:51 -0700 (PDT) Message-ID: [EMAIL PROTECTED] Date: Tue, 10 Apr 2007 09:20:52 -0400 From: andrew strasfogel [EMAIL PROTECTED
Re: [MBZ] OT: 12v lighting
So I spent some time looking at different solutions yesterday and discovered that otherpower.com has instructions for making LED lights. Yes, just know that their power circuits are resistive in nature (even the constant-current LM317 supply) and operate by burning excess voltage as heat. I've yet to see a switching regulator for LED lighting, though I'm sure they exist. That would be best for battery-operated systems. For example, a 3-LED string runs about 10+ volts, about what you get from a 'completely dead' 12V lead-acid battery, so the excess voltage will be burned as heat. Assuming a fully charged voltage of 14V, perhaps 25% of the battery's capacity will be wasted in the resistors and/or LM317. -- Jim
Re: [MBZ] OT: 12v lighting
Check out this application note: AN-H48 Buck-based LED Drivers using the HV9910 http://www.supertex.com/pdf/app_notes/AN-H48.pdf Looks like a way to get 90% power supply efficiency, if the design is carefully done. -- Jim
Re: [MBZ] OT: 12v lighting
Do they have them in standard LED cases? I'd like to try a couple in the dash of my Benz's -- Luther KB5QHUAlma, Ark '87 300SDL (271,xxx mi) needs head '83 300SD (245 kmi) For Sale '82 300CD (166 kmi) '82 300D (74 kmi) getting '85 donor engine '85 300D (280,176) parts car-sans engine Quoting John Robbins [EMAIL PROTECTED]: Jim Cathey wrote: If you're dead set on LEDs... look into anything that uses Luxeon LEDs... I've played with a 3W one... was VERY bright. The datasheet says they output 70-80 lumens. You'd need a 12V to 3V supply though. They look fairly persnickety about what you feed them. Best to be careful, I think they run them right on the ragged edge of death. I bought one just to tinker with... dumped 3V and 1A into it (current controlled benchtop supply), and it didn't complain. Couldn't look near it either... Could always use it at 50% rated power... ;-) John
Re: [MBZ] OT: 12v lighting
Looks cool. I don't understand hardly any of it but it looks cool... How much power am I really wasting at the resistor or LM317? I want to come in under 5w, how much do I plan for at the resistor? Anybody seen the Wallace and Grommit short films? I need a copy of electronics for dogs... -Curt Date: Tue, 10 Apr 2007 07:04:30 -0700 From: Jim Cathey [EMAIL PROTECTED] Subject: Re: [MBZ] OT: 12v lighting To: Mercedes Discussion List mercedes@okiebenz.com Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=US-ASCII; format=flowed Check out this application note: AN-H48 Buck-based LED Drivers using the HV9910 http://www.supertex.com/pdf/app_notes/AN-H48.pdf Looks like a way to get 90% power supply efficiency, if the design is carefully done. -- Jim - 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. From [EMAIL PROTECTED] Tue Apr 10 15:33:40 2007 Received: from an-out-0708.google.com ([209.85.132.243]) by server8.arterytc8.net with esmtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1HbILk-0002dw-FW for mercedes@okiebenz.com; Tue, 10 Apr 2007 15:33:40 + Received: by an-out-0708.google.com with SMTP id b6so2047918ana for mercedes@okiebenz.com; Tue, 10 Apr 2007 08:33:35 -0700 (PDT) Received: by 10.100.32.1 with SMTP id f1mr4961293anf.1176219214622; Tue, 10 Apr 2007 08:33:34 -0700 (PDT) Received: by 10.100.167.15 with HTTP; Tue, 10 Apr 2007 08:33:34 -0700 (PDT) Message-ID: [EMAIL PROTECTED] Date: Tue, 10 Apr 2007 10:33:34 -0500 From: Hans Neureiter [EMAIL PROTECTED] To: Mercedes Discussion List mercedes@okiebenz.com MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Antivirus-Scanner: Clean mail though you should still use an Antivirus Subject: [MBZ] 124 shaking in neutral, more observations X-BeenThere: mercedes@okiebenz.com X-Mailman-Version: 2.1.9.cp2 Precedence: list Reply-To: Mercedes Discussion List mercedes@okiebenz.com List-Id: Mercedes Discussion List mercedes_okiebenz.com.okiebenz.com List-Unsubscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] List-Archive: http://okiebenz.com/pipermail/mercedes_okiebenz.com List-Post: mailto:mercedes@okiebenz.com List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] X-List-Received-Date: Tue, 10 Apr 2007 15:33:40 - Some more careful observations showed that if I kill the engine at high enough speed, the thing gets quiet. There is also a noticeable high amplitude vibration (the sunroof rattles) when sitting idling at a stop with the tranny in drive. Take it to neutral, the rpm does not change, but it gets quiet. Motor mounts, perhaps ? On 4/5/07, Jim Cathey [EMAIL PROTECTED] wrote: Killed the engine, no change. That should pretty much eliminate anything forwards of the middle of the transmission. -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com -- Hans Neureiter, Houston, TX '82 300SD, '95 E300D
Re: [MBZ] OT: 12v lighting
How much power am I really wasting at the resistor or LM317? I want to come in under 5w, how much do I plan for at the resistor? Given that you aim to run the LED's at a specified current, you can get awfully close just by using Ohm's law, in this case P-I^2R. For the LM317, also you lose 1.5I in it as well. -- Jim
Re: [MBZ] OT: 12v lighting
More importantly, WHERE in Maine. I've probably been there. On 4/8/07, Curt Raymond [EMAIL PROTECTED] wrote: Here's one of those ideas I might be shy to float in person... We've got a little camp in Maine, totally backwoods, woodstove, gas lights, you get the idea. On the last couple trips I've been frustrated with trying to read by flashlight in my bunk. The bunk is arranged such that the gas lights are of no use and I can't put a gas light up there because I'd either wack it or catch the roof on fire. I hate flashlights mostly because of the directional nature of the beam and replacing the battery. So I'm thinking to get a 12v LED reading light bulb(2watt), a 12v garden tractor battery and use a 5 watt solar panel I already have to make myself a reading light. I found a site that has the bulb for a somewhat reasonable price (considering it should last a long time) and even in a kit with a fixture. The fixture seems to just be a conventional light fixture with a cigar lighter type plug for which they want $40. So the question: could I take a conventional light fixture and run 12v through it as long as I'm using a 12v bulb? To head off questions, 12v because the inverter would waste alot of power and make noise. LED because CF bulbs wouldn't work well in the cold and yes sometimes I am up reading but too lazy to stoke the fire. I intend to leave the 2 prong connector on the lamp so extension cords will be easier. With a 5w panel I don't think I'll need a charge controller and a 10ah (or whatever they are) garden tractor battery should run my light for a long time. Assuming it works well and my folks want lights like it I'd step up to maybe a 20w panel and charge controller. -Curt - Bored stiff? Loosen up... Download and play hundreds of games for free on Yahoo! Games. ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com -- LT Don The Crazy Coastie
Re: [MBZ] OT: 12v lighting
Yup - sounds like a good plan to me. Go for it. I guess the only question would be whether the beam width of the LED will be adequate for lighting the whole page. On 4/8/07, Jim Cathey [EMAIL PROTECTED] wrote: So the question: could I take a conventional light fixture and run 12v through it as long as I'm using a 12v bulb? Absolutely. I'd be in favor of finding one of those 'tensor' style lamps that already use 12V incandescent bulbs. I bought a couple of those for our camper and removed the 12V transformers in the base. They work wonderfully. -- Jim -- OK Don, KD5NRO Norman, OK Even if you're on the right track, you'll get run over if you just sit there. Will Rogers '90 300D, '87 300SDL, '81 240D, '78 450SLC, '97 Ply Grand Voyager
Re: [MBZ] OT: 12v lighting
ACK! Incandescent... How much light do you think I can get off an incandescent bulb for 2w? Thats the whole point of the LED bulb, lighting using only a 5w solar panel... -Curt Date: Sun, 8 Apr 2007 13:20:38 -0700 From: Jim Cathey [EMAIL PROTECTED] Subject: Re: [MBZ] OT: 12v lighting To: Mercedes Discussion List mercedes@okiebenz.com Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=US-ASCII; format=flowed So the question: could I take a conventional light fixture and run 12v through it as long as I'm using a 12v bulb? Absolutely. I'd be in favor of finding one of those 'tensor' style lamps that already use 12V incandescent bulbs. I bought a couple of those for our camper and removed the 12V transformers in the base. They work wonderfully. -- Jim - Bored stiff? Loosen up... Download and play hundreds of games for free on Yahoo! Games. From [EMAIL PROTECTED] Mon Apr 09 13:35:27 2007 Received: from web32811.mail.mud.yahoo.com ([68.142.206.41]) by server8.arterytc8.net with smtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1Hau1k-00029M-UY for mercedes@okiebenz.com; Mon, 09 Apr 2007 13:35:26 + Received: (qmail 45086 invoked by uid 60001); 9 Apr 2007 13:35:19 - X-YMail-OSG: 6W0zB5gVM1mAmYhMi4h2wArTf_NRHCMrnTvVTS2AmX_B2CUQbn6JB28ld_F_ub1NfQp2L.OXfMV1GODT3.0ei.5Mxp8Mb0f_rH68I10B5EOjMw1XQu.P_FFwX4uU4Q-- Received: from [198.51.119.130] by web32811.mail.mud.yahoo.com via HTTP; Mon, 09 Apr 2007 06:35:19 PDT Date: Mon, 9 Apr 2007 06:35:19 -0700 (PDT) From: Curt Raymond [EMAIL PROTECTED] To: Diesel List mercedes@okiebenz.com MIME-Version: 1.0 Message-ID: [EMAIL PROTECTED] X-Antivirus-Scanner: Clean mail though you should still use an Antivirus Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Content-Filtered-By: Mailman/MimeDel 2.1.9.cp2 Subject: Re: [MBZ] OT: 12v lighting X-BeenThere: mercedes@okiebenz.com X-Mailman-Version: 2.1.9.cp2 Precedence: list Reply-To: Mercedes Discussion List mercedes@okiebenz.com List-Id: Mercedes Discussion List mercedes_okiebenz.com.okiebenz.com List-Unsubscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] List-Archive: http://okiebenz.com/pipermail/mercedes_okiebenz.com List-Post: mailto:mercedes@okiebenz.com List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] X-List-Received-Date: Mon, 09 Apr 2007 13:35:27 - LOL, Caribou. Theres a Coastie station at Easton I think, not terribly far away. -Curt Date: Sun, 8 Apr 2007 19:03:42 -0500 From: LT Don [EMAIL PROTECTED] Subject: Re: [MBZ] OT: 12v lighting To: Mercedes Discussion List mercedes@okiebenz.com Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=ISO-8859-1; format=flowed More importantly, WHERE in Maine. I've probably been there. - The fish are biting. Get more visitors on your site using Yahoo! Search Marketing. From [EMAIL PROTECTED] Mon Apr 09 13:38:18 2007 Received: from sccrmhc12.comcast.net ([63.240.77.82]) by server8.arterytc8.net with esmtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1Hau4Y-0002PG-DE for mercedes@okiebenz.com; Mon, 09 Apr 2007 13:38:18 + Received: from aceraspire (c-69-243-211-95.hsd1.va.comcast.net[69.243.211.95]) by comcast.net (sccrmhc12) with SMTP id 20070409133802012006af19e; Mon, 9 Apr 2007 13:38:13 + Message-ID: [EMAIL PROTECTED] From: LarryT [EMAIL PROTECTED] To: Mercedes Discussion List mercedes@okiebenz.com References: [EMAIL PROTECTED] Date: Mon, 9 Apr 2007 09:37:56 -0400 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Antivirus-Scanner: Clean mail though you should still use an Antivirus Subject: Re: [MBZ] A New Level of Gutlessness X-BeenThere: mercedes@okiebenz.com X-Mailman-Version: 2.1.9.cp2 Precedence: list Reply-To: Mercedes Discussion List mercedes@okiebenz.com List-Id: Mercedes Discussion List mercedes_okiebenz.com.okiebenz.com List-Unsubscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] List-Archive: http://okiebenz.com/pipermail/mercedes_okiebenz.com List-Post: mailto:mercedes@okiebenz.com List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] X-List-Received-Date: Mon, 09 Apr 2007 13:38:18 - Check the air filter - when last changed? Also the fuel filters. Its possible the IP was not adjusted properly. Larry T (67 MGB, 74 911, 78 240D, 91 300D) www.youroil.net for Oil Analysis and Weber Parts Test Results http
Re: [MBZ] OT: 12v lighting
ACK! Incandescent... How much light do you think I can get off an incandescent bulb for 2w? Thats the whole point of the LED bulb, lighting using only a 5w solar panel... Before I did much more I'd really want to try out the proposed light source to see if it was really suitable for reading. The incandescents we use in the camper are very satisfactory. Then there is also duty cycle, how much reading versus recharging time do you expect? If the stay is not indefinite you can even afford to run at a bit of a loss. The last time I looked fluorescent lamps were still king of the lumen/watt rating. That's been awhile now. But there are some very interesting CF lamps in the surplus market that come from laptop screen backlights. Have to factor in the inverter's efficiency though. A LED doesn't eat 12V, so you have to look at how you're planning to power it. Burning it in a simple resistor would mean that you'd only get 1/4 the battery life you should. Need a PWM feed to keep it efficient. Incandescent offers the advantages of extreme simplicity and a satisfactorily wide illumination pattern, but at an efficiency cost. If you're stuck with a 2W bulb you're talking about one of the dashboard lights. That still might be OK, you'd have to try it out, and you'd definitely want a good reflector head. -- Jim
Re: [MBZ] OT: 12v lighting
cost. If you're stuck with a 2W bulb you're talking about one of the dashboard lights. That still might be OK, you'd have to try it out, and you'd definitely want a good reflector head. Oh, and the common Malibu outdoor low-voltage lighting bulb is 4W at 12V. Those are readily available and cheap. -- Jim
Re: [MBZ] OT: 12v lighting
I think perhaps you're a bit behind on the current LED technology. I'm looking at http://store.sundancesolar.com/12v18ledbufo.html Its only 40 lumens but that seems to compare well, I found a chart with a 15w CF that produces 105 lumens. This will only be a reading lamp, I've been using a small battery powered flourescent lamp for awhile. Its okay but not great, not focused enough really. Of course the problem with that bulb is its price. $35 is alot to pay to find out I don't like it... The next choice is a 9w cf which is probably more like 80 lumens although I can find no real documentation on that. Even then I should have some more charging capacity although you're right I'll probably only use the light for 2-3 hours a night so I should have plenty of reserve... -Curt Date: Mon, 9 Apr 2007 07:29:45 -0700 From: Jim Cathey [EMAIL PROTECTED] Subject: Re: [MBZ] OT: 12v lighting To: Mercedes Discussion List mercedes@okiebenz.com Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=US-ASCII; format=flowed ACK! Incandescent... How much light do you think I can get off an incandescent bulb for 2w? Thats the whole point of the LED bulb, lighting using only a 5w solar panel... Before I did much more I'd really want to try out the proposed light source to see if it was really suitable for reading. The incandescents we use in the camper are very satisfactory. Then there is also duty cycle, how much reading versus recharging time do you expect? If the stay is not indefinite you can even afford to run at a bit of a loss. The last time I looked fluorescent lamps were still king of the lumen/watt rating. That's been awhile now. But there are some very interesting CF lamps in the surplus market that come from laptop screen backlights. Have to factor in the inverter's efficiency though. A LED doesn't eat 12V, so you have to look at how you're planning to power it. Burning it in a simple resistor would mean that you'd only get 1/4 the battery life you should. Need a PWM feed to keep it efficient. Incandescent offers the advantages of extreme simplicity and a satisfactorily wide illumination pattern, but at an efficiency cost. If you're stuck with a 2W bulb you're talking about one of the dashboard lights. That still might be OK, you'd have to try it out, and you'd definitely want a good reflector head. -- Jim - Looking for earth-friendly autos? Browse Top Cars by Green Rating at Yahoo! Autos' Green Center. From [EMAIL PROTECTED] Mon Apr 09 20:55:41 2007 Received: from nz-out-0506.google.com ([64.233.162.225]) by server8.arterytc8.net with esmtp (Exim 4.63) (envelope-from [EMAIL PROTECTED]) id 1Hb0to-0002qs-MN for mercedes@okiebenz.com; Mon, 09 Apr 2007 20:55:41 + Received: by nz-out-0506.google.com with SMTP id n29so1196818nzf for mercedes@okiebenz.com; Mon, 09 Apr 2007 13:55:33 -0700 (PDT) Received: by 10.115.18.1 with SMTP id v1mr2474756wai.1176152132445; Mon, 09 Apr 2007 13:55:32 -0700 (PDT) Received: by 10.114.58.4 with HTTP; Mon, 9 Apr 2007 13:55:32 -0700 (PDT) Message-ID: [EMAIL PROTECTED] Date: Mon, 9 Apr 2007 16:55:32 -0400 From: andrew strasfogel [EMAIL PROTECTED] To: Mercedes Discussion List mercedes@okiebenz.com In-Reply-To: [EMAIL PROTECTED] MIME-Version: 1.0 References: [EMAIL PROTECTED] [EMAIL PROTECTED] X-Antivirus-Scanner: Clean mail though you should still use an Antivirus Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.9.cp2 Subject: Re: [MBZ] Off Topic Acura's X-BeenThere: mercedes@okiebenz.com X-Mailman-Version: 2.1.9.cp2 Precedence: list Reply-To: Mercedes Discussion List mercedes@okiebenz.com List-Id: Mercedes Discussion List mercedes_okiebenz.com.okiebenz.com List-Unsubscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] List-Archive: http://okiebenz.com/pipermail/mercedes_okiebenz.com List-Post: mailto:mercedes@okiebenz.com List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com, mailto:[EMAIL PROTECTED] X-List-Received-Date: Mon, 09 Apr 2007 20:55:42 - If you tell us the asking price we can opine intelligently on whether it is a good buy or not. On 4/9/07, Sunil Hari [EMAIL PROTECTED] wrote: They're awesome cars - handle well (not as well as a 124, but you're not paying MB prices either), good mileage, very reliable. Esp. the later model years. Watch out for rear wheel well rust (bane of Honda/Acura) and make sure the timing belt was changed every 90Kmi. In other words, have the timing belt changed before you buy it. Can be very fast, esp. with the optional 6speed manual. I would buy one today. No really. On 4/9/07, Donald Snook [EMAIL PROTECTED] wrote: Anyone know anything about the Acura Legend. I am
Re: [MBZ] OT: 12v lighting
Curt Raymond wrote: I think perhaps you're a bit behind on the current LED technology. I'm looking at http://store.sundancesolar.com/12v18ledbufo.html Its only 40 lumens but that seems to compare well, I found a chart with a 15w CF that produces 105 lumens. This will only be a reading lamp, I've been using a small battery powered flourescent lamp for awhile. Its okay but not great, not focused enough really. Just to throw in my $.02 I'd look into CCFL lights that are typically used for case mods, etc. White ones do exist, but are harder to come by than the colored ones. No idea on wattage or anything though... I think they are certainly bright enough at least (or would be with a simple reflector for half of it). If you're dead set on LEDs... look into anything that uses Luxeon LEDs... I've played with a 3W one... was VERY bright. The datasheet says they output 70-80 lumens. You'd need a 12V to 3V supply though. http://www.luxeon.com/products/line.cfm?lineId=2 They have brighter ones too... G'luck with it! Little projects like these are great fun :-) John
Re: [MBZ] OT: 12v lighting
So the question: could I take a conventional light fixture and run 12v through it as long as I'm using a 12v bulb? Absolutely. I'd be in favor of finding one of those 'tensor' style lamps that already use 12V incandescent bulbs. I bought a couple of those for our camper and removed the 12V transformers in the base. They work wonderfully. -- Jim
