1. HEXAGONAL NUT
18. COUPLING KEY
2. SPACER STUD
19. COTTER PIN
3. HEXAGONAL BOLT
4. SPACER BUSHING
5. LATCH SPRING
6. LEFT HAND LATCH
7. RIGHT HAND LATCH
8. DRIVE LEVER SPACER
9. DRIVE LEVER SPACER
26. INTERLO CK STOP
10. DRIVE SPRING ASSEMBLY
27. INTERLOCK DISC
12. INNER HOUSING PLATE
28. OPEN INDICATOR PLATE
13. OUTER HOUSING PLATE
29. CLOSED INDICATOR PLATE
14. SPROCKET ASSEMBLY
15. RETAINING RING
16. SPROCKET WASHER
33. PLASTIC PLUG
Figure 5-36. Main Disconnect Switch S120, Operating Mechanism, Exploded View (Sheet 2 of 2)
5-47. ASSEMBLY OF MAIN DISCONNECT SWITCH S120.
Assemble switch assembly as follows:
If housing (32, Figure 5-36) is to be replaced, remove bottom plastic plug (33) from replacement housing
(32) to accommodate kirk-key interlock system.
Install two bearings (21) on bearing mounting holes at sides of the housing (32).
Turn housing (32) face down and install internal components one by one by threading through with the
handle (20) shaft. Install the handle (20) in the CLOSED (up) position through the bearing (21) mounted
on the housing (32) side equipped with lock flanges.
Install spacer (22), sprocket (24), two interlock discs (27) and spacer (23). If interlock discs are to be
replaced, remove interlock stops (26) from replacement discs by removing roll pins (25). Position left
interlock disc (27) in relation to the handle shaft as shown in Figure 5-36. The interlock disc (27) furthest
from the handle (20) must be installed so that the beveled side of the interlock stop slots face the handle
and are positioned at the top and bottom of the interlock discs when the handle is in the fully CLOSED (up)
position. Thread through all components with handle (20) shaft, as described in step (3) above until shaft
tip goes through bearing (21) mounted on the other side of the housing.
Secure all components in place by installing cotter pin (19) through spacer (22) and handle (20) shaft.
Align spacer (22) holes with handle shaft hole as necessary to install the cotter pin (19). When installed,
bend cotter pin ends outwards in opposite directions.
Assemble disconnect switch assembly as follows (perform identical procedures for the three blade assemblies):
Attach arc chute support (32), jaw (31, Figure 5-35), and hinge (20) to the base (18) and secure with
hexagon head bolts (33). Align hinge (20) and jaw (31) before finally tightening the hexagon head bolts
Install spacer (26) between second holes from bottom of each blade (19) and secure with hexagon head
bolt (25) and hexagonal nut (24). Position end of connecting link (arc side down) between second holes
from top of blades and secure with similar mounting hardware (24 and 25).
Position spacer (26) between top holes of blades. Position spring (30) and flat washer (29) against outer
side of right hand blade (19) and through to the left blade with rivet (28). Install flat washer (29) at rivet
(28) end and secure with cotter pin (27).
Install completed blade assembly on hinges (20) mounted on base (18) with hinge (20) between the bottom
holes of the blade assembly. Position pivot spring washers (22) at outer side of blades (concave side
inwards) and secure in place using hexagon head bolt (23) and plastic stop nut (21). Thread the
connecting links (8) through slot at middle of the base (18).