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- Date:- Signature of faculty member EXPERIMENT : - 8 DATE: - AIM: - SETTING AND ADJUSTMENT OF HEAD LIGHT OF AUTOMOTIVE VEHICLE.
- Lights Basic lighting circuit
- Sidelights (up to 60 cd)
- Brake lights (40–100 cd)
- Reversing lights (300–600 cd)
- Day running lights (800 cd max)
- Measurement A
- Conclusion Question
- Date:- Signature of faculty member
EVALUATION TABLE
Date:- Signature of faculty member EXPERIMENT: - 8 DATE:- AIM: - SETTING AND ADJUSTMENT OF HEAD LIGHT OF AUTOMOTIVE VEHICLE. OBJECTIVE: The objective of this practical is to aware the student about different lamps and bulbs used in automobile vehicle. By this practical student get knowledge about aligning aiming method for setting and adjustment of headlight. INTRODUCTION It is of utmost importance that your vehicle's lighting system be aimed properly in order for it to perform its best. Lights that are aimed incorrectly will not only perform poorly but may also offend oncoming traffic. When replacing bulbs, it is a good idea to verify that your lights are properly aimed. Slight variances in filament position can translate to large variances in beam pattern. The following procedure does not require special aiming equipment and ensures proper aim. Bulbs Joseph Swan in the UK demonstrated the first light bulb in 1878. Much incremental development has taken place since that time. The number, shape and size of bulbs used on vehicles is increasing all the time. Figure shows a common selection. Most bulbs for vehicle lighting are generally either conventional tungsten filament bulbs or tungsten halogen. In the conventional bulb the tungsten filament is heated to incandescence by an electric current. In a vacuum the temperature is about 2300 ° C. Tungsten is a heavy metallic element and has the symbol W; its atomic number is 74; and its atomic weight 2.85. The pure metal is steel grey to tin white in color. Its physical properties include the highest melting point of all metals: 3410 ° C. Pure tungsten is easily forged, spun, drawn and extruded, whereas in an impure state it is brittle and can be fabricated only with difficulty. Tungsten oxidizes in air, especially at higher temperatures, but it is resistant to corrosion and is only slightly attacked by most mineral acids. Tungsten or its alloys are therefore ideal for use as filaments for electric light bulbs. Lights Basic lighting circuit simple lighting circuit. Whilst this representation helps to demonstrate the way in which a lighting circuit operates, it is not now used in this simple form. The circuit does, however, help to show in a simple way how various lights in and around the vehicle operate with respect to each other. For example, fog lights can be wired to work only when the sidelights are on. Another example is how the headlights cannot be operated without the sidelights first being switched on. External lights Regulations exist relating to external lights, the following is a simplified interpretation and amalgamation of current regulations; the range of permissible luminous intensity is given in brackets after each sub heading. Sidelights (up to 60 cd) A vehicle must have two sidelights each with wattage of less than 7W. Most vehicles have the sidelights incorporated as part of the headlight assembly. Rear lights (up to 60 cd) Again, two must be fitted each with wattage not less than 5W. Lights used in Europe must be ‘E’ marked and show a diffused light. Their position must be within 400 mm from the vehicle edge and over 500 mm apart, and between 350 and 1500mm above the ground. Brake lights (40–100 cd) There two lights are often combined with the rear lights. They must be between 15 and 36 W each, with diffused light and must operate when any form of first line brake is applied. Brake lights must be between 350 and 1500 mm above the ground and at least 500 mm apart in a symmetrical position. High-level brake lights are now allowed and, if fitted, must operate with the primary brake lights. Reversing lights (300–600 cd) No more than two lights may be fitted with a maximum wattage each of 24W. The light must not dazzle and either be switched automatically from the gearbox or with a switch incorporating a warning light. Safety reversing ‘beepers’ are now often fitted in conjunction with this circuit, particularly on larger vehicles. Day running lights (800 cd max) Volvo use day running lights as these are in fact required in Sweden and Finland. These lights come on with the ignition and must only work in conjunction with the rear lights. Their function is to indicate that the vehicle is moving or about to move. They switch off when parking or headlights are selected. PROCEDURE Find a flat level surface adjacent to a vertical white wall where the car can be parked (a garage door is an ideal location at home). Pull the car straight up to the wall as close as possible and draw a vertical line on the wall corresponding to the centerline of the vehicle (this can be done most precisely by using a yardstick and extending it from the hood ornament or badge to the wall). Pull the car straight back until the headlights are 25 feet from the wall. 
Figure 1 Head Light Aiming Make the following two measurements: Measurement A: From the ground to the geometric centre of one of the headlight lenses Measurement B: From one of the low beam headlights to the vehicle centreline. (Also measure from high beam centre to vehicle centreline for 4 headlight systems) Note these measurements. 
Figure 2 Low Beam Measurement Two Headlamp Systems Draw one horizontal line on the wall at a height exactly 2 inches lower than Measurement A made in Step 2. On the line, make vertical marks both to the right and left of the vehicle centerline mark at the distance of Measurement B from the vehicle centerline vertical line. 
Figure 3 Measurement Technique Four Headlamp Systems Draw two horizontal lines on the wall, one at the height measured from the ground to center of the headlight and one at a height exactly 2 inches lower than the measurement from the ground to the geometric centre of the headlight. 
Figure 4 Measurement Technique Two Headlamp Systems Turn the headlights on and adjust the vertical aim of the headlights so that the top horizontal cut off of each of the beams is located along the horizontal line drawn on the wall. Adjust the horizontal aim of the low beam headlights so that the point at which the top cut-off of the beam begins to slope upwards is located at the vertical marks. 
Figure 5 Focus Of Beam On Horizontal Line Four Headlamp Systems Adjust the low beams as in (A) above. Adjust the high beams so that the centre of the illuminated region is located at the cross formed by the upper horizontal line and the vertical marks Conclusion Question Explain the procedure of Aiming of Headlight Explain the setting and adjusting of headlight focusing. Explain the steps to be taken for aiming of headlight for lower beam EVALUATION TABLE
Date:- Signature of faculty member Directory: automobile -> Practical -> sem6 automobile -> Certificate automobile -> Arslan Khan Durrani automobile -> Address to the Australian Automobile Association automobile -> Advancing integrity automobile -> Automobile Production automobile -> Training plan automobile mechanic automobile -> Delete box, or place text or logo here sem6 -> Department of automobile engineering sem6 -> Department of automobile engineering Download 317.85 Kb. Share with your friends:
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