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ADR46/00 - Headlights
ADR77/00 - Gas Discharge (HID) Headlamps #1
ADR77/00 - Gas Discharge (HID) Headlamps #2
ADR78/00 - Gas Discharge (HID) Light Sources
HID HEAD LIGHTING
LOW POWER CONSUMPTION: ONLY 35watts each bulb.
3 TIMES BRIGHTER: OVER 3200 Lumens.
EXTREMELY LONG LIFE: OVER 2500hours.
LOW POWER CONSUMPTION
The xenon bulb provides more than twice the amount of light of a halogen bulb, while only consuming half the power. Therefore, the driver can see more clearly an the car has more power for other functions. Morevoer, it is environmentally friendly, as less power means less fuel consumption.
3 TIMES BRIGHTER
The clear white light produced by the Xenon bulb is similiar to daylight. Research has shown that this enables drivers to concentrate better. Furthermore, this particular light colour reflects the roadmarkings and signs better than conventional lighting.
EXTREMLY LONG LIFE
The Xenon bulb also deliers a marked contribution to road safety in the event of limmited visibility due to weather conditions. In practical terms, the life span of the bulb is equal to that of the car, which means that the bulb need only be replaced in exceptional cases.
Automotive Xenon Metal Halide HID Lamps
Written by Don Klipstein ( http://members.misty.com/don/d2.html ) with some bits changed and added by Dave Maunder (bushy555)
Introduction
The automotive HID (high intensity discharge) headlight lamps are often referred to as xenon lamps but they are more of a specialized metal halide lamp than anything else.
The main part numbers are:
D2S - plain
D2R - like D2S but with heat-resistant black paint on spots to control the light output pattern
D1S - like D2S, but with integral ignitor
D1R - like D2R but with integral ignitor
The above are 35 watt lamps. D2S and D1S types nominally produce 3200 lumens of light and the D2R and D1R types nominally produce 2800 lumens of light.
Description of the Lamp / Bulb
This sort of lamp consists of a tubular outer bulb approx. 10 mm (.4 inch) in diameter which contains the arc tube (inner bulb). The outer bulb is made of special quartz such as cerium-doped quartz which blocks most ultraviolet, especially the more dangerous short and medium wavelengths as well as much of the 365-366 nM longwave mercury line cluster.
The arc tube or inner bulb is made of plain fused quartz and has tungsten electrodes with the distance between the tips approx. 4.2, maybe 5 millimeters (approx. or slightly under .2 inch). Its resembles that of a miniaturized short arc lamp, but true short arc lamps have a much more concentrated arc.
The arc tube has xenon gas in it at a couple of atmospheres to maybe a few atmospheres when cold and a few to maybe several atmospheres when hot. There is also mercury in the bulb, and when it is vaporized the mercury adds at least 20 atmospheres of pressure for a total pressure of around or maybe even over 30 atmospheres.
Metal halides - salts - are also in the arc tube. The formulation in automotive HID lamps includes sodium and scandium halides (probably iodides) and maybe traces of others such as lithium and thallium halides.
More ordinary metal halide lamps do not have high pressure xenon but have low pressure argon instead. The high pressure xenon is used to obtain some usable light output during warmup before the other ingredients have vaporized.
Safety and Reliability Requirements Please note that D1 and D2 type bulbs operate at high temperature with great pressure probably near or over 30 atmospheres. The internal quartz arc tube temperature is probably typically around 800 degrees C (1400-1500 degrees F or so). The outer bulb is not this hot, but it is definitely burning hot. The arc tube always has at least some miniscule risk of exploding and should only be operated in a headlight housing or other suitable container. Improper operation increases the risk of bulb explosion. The bulb must be clean and free of dirt, grease, organic matter, ash, salt, or alkali. Salts, ash, and alkalis have a tendency to slowly leach into red-hot and nearly red hot quartz which will result in strains, weak spots, and maybe cracks. A metal halide lamp does not like frequent starting. D1 and D2 types can be blinked, but this should only be done for a limited amount of time. Starting causes wear on the electrodes. Excessive evaporation of electrode material will deposit it onto the inner surface of the arc tube which results in darkening and overheating of the arc tube. In D1 and D2 and some other metal halide lamps, there is a halogen cycle which cleans deposited tungsten electrode material from the inner surface of the arc tube. Prolonged continuous operation at proper internal temperatures is required for the halogen cycle to work.
Legality of Auxiliary Headlights ADR 77 covers everything about Gas Discahrge Headlamps. We’re not interested at all in headlamps, but what the ADR call “auxiliary driving lamps”, or commonly known to the rest of us as “spotties”.
All my searches so far on the exact wording of this matter have ended up with very little information. Lightforce 240HID’s and Hella Predators are legal within Australia. Lightforce XGT has the exact same lens as that of the Lightforce 240HID. Hella Rallye 4000 has the exact same lens as that of the Hella Predator.
Electrical Requirements
The electrical requirements of D2 type lamps are nasty. They require ballasts which are more difficult to homebrew than other ballasts. I strongly encourage hobbyists, do-it-yourselfers, and hackers to *NOT* try this. Try homebrewing a D2 ballast only if you have the patience of two saints, lots of electrical and electronic project skills including high voltage skills and skill in homebrewing high voltage transformers with the combined difficulties of flyback transformers and xenon trigger transformers, and a budget for replacing lots of blown parts before you get it working. You are better off buying ballasts from Osram, Bosch, or Aromat (a division of Matsushita) or others. For one thing, these lamps require special sockets made by few manufacturers and mostly sold only to ballast manufacturers. The D2 types require a starting pulse. 7 kilovolts may on an average spark through these bulbs, but for reliability you need more, maybe 10 or possibly 12 kilovolts. Automotive use requires ability to restart a hot bulb with the mercury vapor pressure high, and this requires even more voltage - 12 to 15 kilovolts and maybe even more for good reliability. The usual ballasts supposedly produce starting pulse voltages like 18 kilovolts minimum, 20 kilovolts typical.
D1 types have an integral ignitor which the ballast has to work with.
Starting pulses must be repeated frequently until the arc is established. The ballast must supply an open circuit output voltage - other than the starting pulses - of over 300 volts, preferably 400 or maybe preferably 450 volts - to force the arc to establish. D1 and D2 type lamps are 35 watt lamps. Once the arc is established, the ballast must supply limited current or else the arc will draw extreme current and this will be bad for the bulb and/or other parts. The voltage across the lamp is normally around 80-90 volts when it is warmed up, but will be less during warmup. The ballast must handle a lamp voltage possibly as low as 16 volts early in warmup, although this voltage usually bottoms out higher - probably at least in the 20's of volts. The ballast must deliver 35 watts to the lamp when the voltage across the lamp is between 70 and 110 volts. When this voltage is lower, the ballast must deliver at least .5 amp but generally no more than 2 amps and preferably as close to 35 watts as possible. Higher currents are preferred - a partially warmed up metal halide lamp sometimes has an unstable arc at lower current. An automotive grade ballast often delivers boosted power (above 35 watts) at some times during warmup to give near-full light output. Note that a xenon arc or a mercury vapor arc does not produce visible light as efficiently as a metal halide arc does. Automotive grade ballasts with boosted power at some points of warmup have circuitry that models the thermal characteristics of the bulb. The maximum safe current for the bulb's electrodes must not be exceeded during a power boost during warmup. A voltage across the bulb higher than 110 volts only occurs in the early stage of establishing the arc or if the bulb is failing. The ballast should deliver enough power to heat up the electrode tips enough for the arc to establish - more is better and over 35 watts is OK as long as the current is not excessive. But excessive power delivered to an aging bulb can cause the bulb to explode.
D1 and D2 lamps and most other metal halide lamps require AC. DC is tolerable briefly, and then preferably only if the bulb is cold. A DC electric field, hot quartz or hot glass, and salts or alkalis is not a good combination - electrolysis effects can occur which can create weak spots or cracks in the arc tube. The AC delivered to a D1 or D2 type bulb usually has a frequency of a couple hundred to a few hundred Hz. Higher frequencies are probably OK with D2 types but the ignitors in D1 types may only work correctly or even be adequately conductive in a certain range of frequencies.
The AC current waveform in a D1 or D2 type lamp is traditionally a squarewave or close to a squarewave. Other waveforms have higher peak current for a given average current or RMS current, and the higher peak current is harder on the electrodes and may shorten the life or cause problems with the use of higher currents during warmup.
Metal halide lamps should not be overpowered, except where permissible for accelerated warmup and near-full light output during warmup. Overpowering one will shorten its life and increase the risk of the lamp exploding.
Underpowering a metal halide lamp is also bad. If the electrodes are not hot enough, they do not do a good job of conducting electrons into the arc and voltage drop in this process (known as the "cathode fall") is excessive. Excessive cathode fall causes positive ions in the arc to hit the electrode at excessive speed which "sputters" electrode material onto the inner surface of the arc tube. It is not recommended to experimentally operate metal halide lamps at reduced power. Besides the bad effects of high cathode fall on hot electrodes, an unusual temperature pattern can have the chemicals in the arc tube condense in locations that can block some of the light. And if the electrode cathode falls are excessive and unequally so, a DC electric field can result, which can cause destructive electrolysis effects on hot salts on hot quartz. This can cause the arc tube to crack. Metal halide lamps should have power input within 10 percent of their rated wattage.
Why some HID lights stay “blue” after warm-up
- by Ekooke (and bits added and changed by Dave Maunder - bushy555)
1) To capture the blue light produced at the arc terminators on a continuous basis, some OEM manufacturers design (deliberately point) a small portion of the reflector to capture the “flat” blue light generated at the anode, and incorporate it as part of the total light output, by design.
2) Other OEMs will just “leave it alone”, knowing that, after a 100 hours or so of “burn time”, the anode will change shape, because of the constant electrical discharge. When this shape change occurs, the anode is no longer ground flat, and the shape of the blue secondary light at the anode changes from a flat, nearly two-dimensional, shape, to something that is three-dimensional. At this time you have something that the reflector can use, and, you’ve got blue-tinted light, all the time.
3) A trend for “blue” lights has caused several HID capsule makers to “fiddle with” the metallic salt mix just for the aftermarket. By incorporating different metals, specifically Indium, the HID arc can continuously fluoresce at higher color temperatures with the same amount of voltage as used in the “lower color temperature” HID capsules. Results have been mixed, depending on the optics of the final applications. This is due to the “stratified light” nature of the stabilized HID arc, and how the reflector focuses on the total arc “layers”. Also, the use of different metallic salts may also decrease the useful life of the HID capsule, through quicker metal deposition on the capsule walls. Note: Indium is a material also used to plate mirrors, via a cathode/anode process.
Info on HID lights. – blue light output
Without going into the physics of electron orbits, photon pumps, valences, and other arcane stuff, it has to do with;
The ballast/igniter, the nature of the arc terminators (cathode -, and anode +), the ignition (startup) current, the vaporizing metallic salts, and the constant Xenon gas fill.
When a cold (room temperature) automotive HID is first turned on, the startup voltage produced by the igniter (sometimes separate, sometimes integrated into the ballast) is in the neighborhood of 20,000-25,000 volts. This high voltage potential forces the current at the arc generating point (cathode -) to leap the gap to the arc receiving point (anode +), identical to what happens with an arc welder. As the “leaping arc” contacts the anode, a number of interesting things start to happen;
1) Light is produced along the arc length, through excitation of the gas molecules of the (constant) Xenon-fill gas.
At this point, the arc is quite “fat” and at a very high color (blue) temperature.
2) Robust high temperature blue light is also produced at the anode surface, and (to a lesser extent) at the cathode.
3) This secondary light source (above) is extremely blue (+/- 10,000K), and also semi-spherical in nature, which
allows this light source to be reflected by the system’s optics.
4) The arc welder process generates heat, causing the metallic salts also contained in the capsules to begin to
vaporize into gas, or gasses. This heating process causes other changes:
5) As the gasses are generated, pressure inside the capsule begins to rise, from a static pressure of 5 atmospheres
(from the Xenon fill), to a terminal point of more than 30 atmospheres. Total pressurization takes (typical) 30
seconds to occur.
6) As the pressure increases in the capsule, less voltage is required to sustain the arc (electron flow), and the ignition current is dropped, via the ballast sensing circuitry, in a tapering fashion. This causes the arc to shrink in diameter and stabilize, as well as reduce the electrode surface sources of “blue” light. Note: The electrode (secondary) light sources are now very flat, like an LED, making them difficult to be captured by the reflector surface, because the reflector is designed to reflect axially produced light. What happens at this point is that the blue light (apparently) goes away. This is because; the arc is shrunken and stabilized, the voltage has been reduced to “arc sustaining”, the fluorescing gasses are running at a lower color temperature, and most of the usable (i.e., by the reflector) light is being generated just along the arc’s axial length. This “sustaining arc” has very little visible blue light, and the flat electrode-generated light is “invisible” to the reflector. Result: No more blue light.
The following was grabbed from http://www.offroaders.com
(with bits changed and added by Dave Maunder - bushy555)
High-intensity discharge (HID) lamps include these types of electrical lamps: mercury vapor, metal halide (also HQI), high-pressure sodium, low-pressure sodium and less common, xenon short-arc lamps. The light-producing element of these lamp types is a well-stabilized arc discharge contained within a refractory envelope (arc tube) with wall loading in excess of 3 W/cm² (19.4 W/in.²). Compared to fluorescent and incandescent lamps, HID lamps produce a much larger quantity of light in a relatively small package.
Construction
HID lamps produce light by striking an electrical arc across tungsten electrodes housed inside a specially designed inner fused quartz or fused alumina tube. This tube is filled with both gas and metals. The gas aids in the starting of the lamps. Then, the metals produce the light once they are heated to a point of evaporation.
Types of HID lamps include:
Mercury vapor (CRI range 15-55)
Metal halide (CRI range 65-80, ceramic MH can go to 90's)
Low-pressure sodium (CRI 0 owing to their monochromatic light)
High-pressure sodium (CRI range 22-75).
Mercury vapor lamps, which originally produced a bluish-green light, were the first commercially available HID lamps. Today, they are also available in a colour corrected, whiter light. But they are still often being replaced by the newer, more efficient high-pressure sodium and metal halide lamps. Standard low-pressure sodium lamps have the highest efficiency of all HID lamps, but they produce a yellowish light. High-pressure sodium lamps that produce a whiter light are now available, but efficiency is somewhat sacrificed. Metal halide lamps are less efficient but produce an even whiter, more natural light. Coloured metal halide lamps are also now available in red, green, blue and yellow
XGT with HID H3, halogen bi-pin, standard halogen H3, HID H1, halogen H1. Lightforce Blitz new and old bi-pin bases
Auxiliary devices Like fluorescent lamps, HID lamps require a ballast to start and maintain their arcs. The method used to initially strike the arc varies: mercury vapor lamps and some metal halide lamps are usually started using a third electrode near one of the main electrodes while other lamp styles are usually started using pulses of high voltage.
Applications
HID lamps are typically used when high levels of light over large areas are required, and when energy efficiency and/or light intensity are desired. These areas include gymnasiums, large public areas, warehouses, outdoor activity areas, roadways, parking lots, and pathways. More recently, HID lamps, especially metal halide, have been used in small retail and residential environments. HID lamps have made indoor gardening practical, especially for plants that require a good deal of high intensity sunlight, like vegetables and flowers. They are also used to reproduce tropical intensity sunlight for indoor aquaria. Some HID lamps such as Mercury Vapor Discharge produce large amounts of UV radiation and therefore need diffusers to block that radiation. In the last few years there have been several cases of faulty diffusers, causing people to suffer severe sunburn and Arc eye. Regulations may now require guarded lamps or lamps which will quickly burn out if their outer envelope is broken. Recently, HID lamps have gained use in motor-vehicle headlamps. This application has met with mixed responses from motorists, mainly in response to the amount of glare that HID lights can cause. However, many motorists still prefer these lights as they emit a clearer, brighter, more natural appearing light than normal headlamps. They almost always have an automatic self-leveling system to minimize this issue and as such are usually an expensive optional extra on most cars. HID lamps are also being used for all external lights on the Airbus A380 superjumbo airliner and on many other general aviation aircraft for landing and taxi lights.
Watts
Watts is a measurement of the current draw. A watt is the unit of electrical power equal to 1 ampere (amp) under a pressure of 1 volt. (Its also equal to 1/746 horsepower for what it's worth). Amperes are the rate at which electricity flows through a wire or piece of machinery. A good analogy is water through plumbing. When you open a faucet on a sink, water flows out at a certain rate. The same thing occurs when you turn on an auxiliary light. Electricity flows at a certain rate. This is amperes. Watts are the amount of energy a device uses in performing its function. To get watts, you multiply volts x amps. For example, a typical set of offroad auxiliary lights might draw about 4.6 amps. 12 volts x 4.6 amps = 55.2 watts. To get amperes, divide watts by volts. Examples: 55 watt auxiliary lights would calculate like this: 55 watts / 12 volts = 4.58 amps. In the home a 100 watt light bulb would calculate this way: 100 watts / 240 volts= 0.416 amps.
Candlepower
One candlepower is the radiating power of a light with the intensity of one candle. This unit is considered obsolete as it was replaced by the candela in 1948, though it is still in common use. 1 candlepower is equal to about 0.981 candela. *
Candela
The standard unit for measuring the intensity of light. The candela is defined to be the luminous intensity of a light source producing single-frequency light at a frequency of 540 terahertz (THz) with a power of 1/683 watt per steradian, or 18.3988 milliwatts over a complete sphere centered at the light source. *
Lumen
The standard unit for measuring the flux of a light being produced by a light source. One lumen represents the total flux of light emitted, equal to the intensity in candelas multiplied by the solid angle in steradians (1/(4.pi) of a sphere) into which the light is emitted. * (source: Russ Rowlett at unc.edu)
With Offroad lights different light sources could have the same power requirements, but vastly different light output. The primary factor of candlepower are the bulb itself. The light itself is then influenced by the reflector placed behind the bulb, reflecting the light outward towards the target area. The brighter and more efficient the bulb is the more light it will produce using less energy. When a bulb produces light, some of the energy is wasted by producing heat. The more efficient a bulb is at creating light, the less heat it will produce. An LED light (light emitting diode) are a prime examples of efficiently generating light with very little energy wasted as heat. Therefore LED lights consume a less amount of energy then incandescent bulbs. However LEDs are not high light producers when compared to other bulbs typically used in offroad lights. Typically Quartz Xenon bulbs and standard halogen bulbs are used.
The reflector's role is to "reflect" the light generated by the bulb. Most of the light projected from an offroad auxiliary light is actually from the back and sides of the bulb and not projected directly from the bulb itself. Therefore the better the design of the reflector the more light will be reflected outward towards the target area. With the reflector size matters. The larger the reflective area of a light, the more light will be reflected out towards the target area. The shape of the reflector is also important. A well engineered reflector will produce a desirable spread of light on the area in front of it. The shape of the area can differ from manufacturer to manufacturer. Some manufacturers design into the light reflector the means to change the focal length so you can change the spread of light from a more point point to a flood of light. Because light from a bulb emits in all directions, the more efficient design of a light is a broad, somewhat deep circle shaped reflector. The least efficient is the small egg shape or rectangle lights that reflect less light. With the reflector, the reflective surface should reflect as much light as possible with a mirror like finish and deteriorated reflectors will obviously have a negative effect on the light emitted.
A good set of offroad lights will have a combination of the best factors, a highly efficient, very bright bulb and a large, broad, weather tight reflector. Reviews can be good sources of information to get opinions on popular offroad lights as well as new lights as they become available on the market.
single 50w 5000k, Four 100w halogen Blitz's
45w 5000k, 35w 6000k
Sway's famous piccy - from www.candlepowerforums.com
