Step 3:Winding extra round of tension wire
- Once again hold the spring case firmly so that it
cannot remove the already applied tension.
- Now, while spring case is firmly held, take the
extra length of tension wire that is just stretched,
and wind an extra round around the spring case.
- Make sure that the tension wire is firmly
stretched around the spring case as mentioned
earlier.
Step 4: Restoring tension wire and its lock
-Once 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 restore 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.
5
