Step 3: Rewinding entire tension wire around
spring case
NOTE:
- Now that the old tension wire is unwound and
new tension wire is attached with the spring case
only at its end, start winding it around the spring
case turn by turn in the anti-clockwise direction
when the spring case is seen from the side of
pantograph as shown in the adjoining diagram.
Keep the tension wire firmly stretched
around the spring case in this process. If the
tension wire is left loose, itmightgetcoiled.Inthat
case, entire tension wire would have to be
opened and rewound around the spring case
again..
Step 4: Restoring tension wire and its lock
- Once the tension wire is completely wound
around the spring case adjust the tension into the
tension wire as explained in the previous pages.
- After the tension in the tension wire is set, take
the end of the wire and pass it thorough the
tension wire stud at upper part of pantograph as
shown in the adjoining diagram.
- Make sure that the spring case is held firmly
while doing this otherwise it will unwind (because
of the tension in its spring) and the already
applied tension will be removed.
- After passing the tension wire through the
tension wire stud and fasten the tension wire lock
at its end.
- Now loosen the spring case lightly (but still keep
on holding it). As a result the spring case will wind
itself (because of the tension in its spring) with the
extra length of tension wire that is left.
- Mount the pantograph on the sliding track and
restore the light on the pantograph. Press the
locking lever and move pantograph up-down 3-4
times to check the tension.
7
