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To gain access to the flag assembly, to replace parts or check the settings, it is
necessary to dismantle the module. Once access to the flag assembly, mounted on
the front plate of the relay, has been gained, adopt the following procedure:
(i) Remove the screw holding the side plate to the top plate and remove the side
plate. This will reveal the miniature relay and the flat spring. Access is
possible through the side of the assembly unless impeded by other
components.
(ii) Remove the 3 screws (2 at the top, 1 at the bottom) holding the printed circuit
board to the top and bottom plates. The circuit board, with the miniature relay
can now be withdrawn from the flag assembly.
(iii) Remove the 2 screws holding the flag spring and clamp plate to the bottom
plate. The flag spring can now be extracted from the assembly.
Note that the top and bottom plates cannot be removed from the relay front plate
without damaging the adhesive name plate, which covers the heads of the
countersunk screws holding the top and bottom plates to the front plate.
Assembly is in the reverse order of dismantling.
6.10.1 Setting up procedure for the flag assembly.
Flag spring units are supplied pre-bent and should need no further adjustment before
assembly.
With the flag spring and printed circuit board carrying the miniature relay assembled
to the top and bottom plates check the settings:
(i) Lift the flag spring to the latched position so that the tab on the flag spring
rests on the catch on the relay,
(ii) With a gap of 0.4mm between the inside face of the armature and the core,
the flag should remain latched.
With a gap of 0.15mm the flag should drop. If necessary carefully bend the tab
to fulfil these conditions.
These tests should be performed by positioning an appropriate feeler gauge
between the armature and coil and then energising the coil with the
appropriate voltage to pick up the relay.
(iii) With the flag in the latched position the spring should exert a force of 10 – 12
grams on the catch. This is checked using a gram gauge, just lifting the flag off
the catch.
(iv) With the flag in the latched position the white stripes on the flag should show
evenly through the slots in the nameplate. Adjustment is made by slackening
the pcb fixing screws and moving the pcb assembly up or down as necessary,
then re-tightening the screws. After adjustment of the pcb the catch
engagement must be rechecked as in (ii).
(v) Allow the flag to drop (by energising the relay coil). The red stripes should
show evenly through the slots in the nameplate. Adjustment is made by
bending the tabs, one on each side of the bottom plate.
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