Mean Green Posted September 20, 2005 Share Posted September 20, 2005 I had an idea last night and wanted to get some thoughts on it. In short, could I include a dim dip unit in my circuit to have my A-bar spot lamps and 4 roof light dimly light with the side lights. Effectively the same as having position lights in the lamps themselves? Has anyone tried this? Is there any reason why I couldnt do it? I plan to wire the lamps to come on with mainbeam but have an isolator switch to allow them to be switched off. Quote Link to comment Share on other sites More sharing options...
fisha Posted September 20, 2005 Share Posted September 20, 2005 i suppose you could do it. How you would do would be a different story. I suppose you could base it on the existing dim-dip units already present the main headlights, but i dont know the specs of how they work. Also, if your running the lights at low current / low voltage ( which ever way the dim-dip circuit qorks ) your still running the filaments outside their normal working range . . . which contributes to the life span one probably being shortened. Quote Link to comment Share on other sites More sharing options...
02GF74 Posted September 20, 2005 Share Posted September 20, 2005 I don't understand what you're on about. You want to put twin element bulbs (main and full) in the roof bar or you want single element bulbs in the roof bar to be lit dimly? Firstly roof bar lamps are not legal on the roads; pretty sure this has been discussed before so the main/full bulbs in the roof bar have no real purpose. Lighting them up so they barely glow again serves no road pupropse. (sereis headlamsp are like that as standard ) Both of these can be done but don't see the point, probably 'cause I don't understand the question. Quote Link to comment Share on other sites More sharing options...
Mean Green Posted September 20, 2005 Author Share Posted September 20, 2005 OK put simply.... Could I add a second dim-dip unit to make my spot lamps (both A-bar and roof) light up like the dim-dipped headlights on my Defeender? The alternative would be to drill a small hole in each lamp and fit a small bulb or LED. I am aware of the legalities concerning roof lights and road driving. Quote Link to comment Share on other sites More sharing options...
02GF74 Posted September 20, 2005 Share Posted September 20, 2005 main (aka dipped) and full beam are different to side lamps. Side lamps as you say use a little bulb. Other than drilling into the bowl with the risk of damaging the silvering the only way would be to fit a headlamp unit that has the side lamp bulb fitted. Another possiblily is to have relays that wire up pairs of spotlamps in series so in effect they are supplied with 6 V but that may make them look yellow?. One more way would be to pulse them, I think that is what volvo do in their headlamps; basically is turning the on/off switch rapidly so should be white than having them in series (I think ) Quote Link to comment Share on other sites More sharing options...
mpb Posted September 20, 2005 Share Posted September 20, 2005 Ive seen this done on a couple of Disco's with lights on an A bar. I think they are Hella lights with a seperate bulbs, that are wired into your side lights. You also have a normal halogen bulb that comes on with main beam. Help this heps Martin 1996 Defender 90 Quote Link to comment Share on other sites More sharing options...
Mark Posted September 20, 2005 Share Posted September 20, 2005 I may be missing the point but I have never seem a 'Dim-dip' unit... Your headlamps have twin filament lamps, and are just switched via a relay, to give either Dip beam (low power filament) or dip and Main (both). usually these are something like 55W and 100W in the same bubble. Sidelights are often added to head lights to give a kind of pilot light type effect, but this requires using a bowl with the pilot light fitted... If I have mis understood, then sorry... Cheers Mark Quote Link to comment Share on other sites More sharing options...
Kev Baldwin Posted September 20, 2005 Share Posted September 20, 2005 Come on now, own up. It's the wannabe trucker look you're looking for isn't it Roadpro offer several types of spotlamp with the in-built 'pilot light' or sidelight facility I think you're looking for. These start from around £15 up to £50 for Hella's. Make sure you check whether the bulbs (if supplied) are 24v or 12v. Quote Link to comment Share on other sites More sharing options...
fisha Posted September 20, 2005 Share Posted September 20, 2005 for those that are unsure.... the defender light circuit has a dim-dip unit. when you only have your side lights on, the circuit lights the halogen dipped beam circuit as well, but it only supplies the bulb with 1/6 of what it would normally get. So your main light bulb ( that H4 one with the dipped and full beam ) actually lights up dimly with the side lights. Greg is wanting to have the same effect with his other lights. Quote Link to comment Share on other sites More sharing options...
Mark Posted September 20, 2005 Share Posted September 20, 2005 Ah, that makes more sense, Sorry I misunderstood... We series boys are lucky to have headlights at all... those two weeks a year when the glow worms are on holiday is a nightmare... Mark Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted September 20, 2005 Share Posted September 20, 2005 The dim dip unit sits in the binnacle behind the dash and is bolted to the bulkhead. The unit is solid state (it acts just like a constant voltage regulated power supply) and IIRC just uses a couple of mediocre power transistors on the output. These units are known to fail and retail at about £65 each. There is an early version which is twice the price and the later version. They are completely interchangeable. The early unit was deigned for sealed beam units and the later one for halogen headlamps. Ralph will be along later with the part numbers. I have looked at a couple of faulty units and on both occassions the ouput devices had bunrt out and made a mess of the circuit board. I would suggest that it was designed just to sink the current from 2 headlamps. In a similar manner to the power transistors in a regulated power supply, the supply voltage minus the regulated voltage, multiplied by the current drawn, will tell the amount of dissipation in watts that the output transistors will have to sink ……. and from what I can remember that unit would not be capable of sinking a huge amount of current. Buy some nice pose worthy angel eye lamps (I see that Ring make them now)…. interestingly the outer rings on these are normally fed from a high brightness LED’s. Ian 90 V8EFI TruckCab Torque wins races ……. BHP sells cars……….and there’s no substitute for cubic inches. Quote Link to comment Share on other sites More sharing options...
western Posted September 20, 2005 Share Posted September 20, 2005 Ralph will be along later with the part numbers. Dim Dip aka voltage transformer 2 types for ------------ quartz halogen light---------------PRC8123----------------Microcat Jan 2005 says £59.11 + vat sealed beam lights-----------------PRC6336-----------------------------------------------100.07 + vat Quote Link to comment Share on other sites More sharing options...
Mean Green Posted September 20, 2005 Author Share Posted September 20, 2005 Hmm OK maybe that idea wont work then. I had a feeling that there would be a logical explaination as to why I couldnt do it. Oh well back to the drawing board. Quote Link to comment Share on other sites More sharing options...
imspanners Posted September 20, 2005 Share Posted September 20, 2005 You could do it, and using 2nd hand Ford dim-dip relays would make it reliable and cheap. They'd have to be wired up in pairs, eg inner and outer, but remember, it's a Landy, anything is possible! Quote Link to comment Share on other sites More sharing options...
02GF74 Posted September 21, 2005 Share Posted September 21, 2005 ok, have to ask ........ but why? What use is having a lightbar glowing dimly above your head? Quote Link to comment Share on other sites More sharing options...
Mean Green Posted September 21, 2005 Author Share Posted September 21, 2005 ok, have to ask ........ but why? What use is having a lightbar glowing dimly above your head? Dunno ask the hundreds of truckers with position lights on their roof lights. Just wondered if it could be done. Quote Link to comment Share on other sites More sharing options...
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