ABB UniGear ZS1 Instruction Manual page 55

Figure 83: 12/17.5kV panels - Top-mounted box with earthing switch for busbar earthing
77 Top-mounted box for top-mounted
earthing switch
78 Operating mechanism box
78.1 Operating shaft
78.2 Slide
• Hexagonal shaft from the operating mechanism box must be pushed through into the bevel gear of
the earthing switch. Sequence and angles of the part must be restored!
• Connecting bars 2.2 with the branch conductors 2 at the junction point must be screwed together
according to figure 5/26 and 5/34. However, if necessary, additional spacer plate 3.3 or 3.2 and
threaded plate 3.4 or 3.8, as well as the screw fixing material from the "top-mounted box for earthing"
set of bags must be used;
• Insulating cover 58 must be brought into position as described in section 5.4.
Note
The auxiliary switches for the earthing switch are adjusted at the works. Problem-free operation is only
guaranteed if the working elements on the hexagonal shaft are correctly mounted.
Because of final installation of the earthing switch and operating mechanism on site, it may be
necessary to make precise adjustment of the auxiliary switches.
In that case, the following is important:
• The auxiliary switch OFF 78.5 must be operated:
- before slide 78.2 has uncovered half of the opening in front of the hexagonal shaft and;
- before the lower edge of the slide has touched the anchor of locking magnet 78.6;
• The auxiliary switch ON 78.4 must be operated:
- before the toggle spring of the earthing switch has reached its dead centre point;
• The push-rod of the auxiliary switch must still have about 0.5 mm to go to the end position in the
operated position.
77
78.1
78.4 Auxiliary switch ON
78.5 Auxiliary switch OFF
78.6 Locking magnet
78
53