ELECTRICALS
16
Fig. 15 Head Lamp
Head Lamps :
The Head Lamp provides two types of light beams - a
high beam to givemax. light well ahead of vehicle and a
lowbeamwhich is shorter and lower so that it shouldnot
dazzle the oncoming drivers and can be used in low
visibility area. Head lamp also has parking lamp
The head lamps must be properly aligned in order to
obtainmax., proper road illumination and reduced glare
for oncoming traffic. It is recommended to check
alignment of head lamp beams periodically.
Adjusting Head Lamp Focus with the Help of Screen
(RHD)
The vehicle should be parked tenmeters away from the
screen on flat ground with its centre in-line with central
vertical line on screen and screen at right angles to
longitudinal axis of the vehicle.The vehicle should be in
unloaded condition with no sag in suspension springs
and all tyres equally inflated.
On themarked up screen as shown in Fig. 16, area above
horizontal and inclined lines (shaded) is called‘Dark Zone’
and the area below is called as the Illuminated Zone.
Each head lamp is aligned individually by masking the
other head lamp. Head lamp is first adjusted for proper
height of lowbeamby adjusting screw (Fig. 16) at its top.
The rubber grommet fitted on cab above head lamp is
required to be unscrewed and removed for accessing
the head lamp adjusting screw. Light from low beam
should fall below horizontal and inclined lines. No light
should fall above these lines
i.e.inDark Zone.Thereafter
lateral adjustment is done by adjusting screw (H) at the
bottom of head lamp so that contour of low beam
coincideswith contour formedby horizontal and inclined
lines below“Dark Zone”.
When properly adjusted, most brightly illuminated area
will be just below the inter section point ‘A’of these two
lines.
Now switch ‘ON’ high beam. They will be symmetrical
above points ‘A’ & ‘B’ of intersection of vertical lines and
horizontal lines.
It is possible that high beam may not be exactly
symmetrical but for this reason head lamp should not be
realigned. Preferably alignment should be done in dark.
Note :
While adjusting head lamps with levelling switch,
keep the levelling switch at ‘0’ position.




