ABB UC Series, Руководство по обслуживанию

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Maintenance guide UCG |
1ZSE 5492-124 en, Rev 6
4.6 Replacing the fixed main contacts
Unscrew the fixed main contacts, see Fig. 15. Mount new
contacts. Use new conical spring washers and locking nuts.
Put the washers as shown in the figure. Press the contacts
against their bracket when tightening the screws. Tightening
torque approximately 10 Nm, (not critical).
The conical end of the nut should be turned upwards.
4.7 Replacing the fixed transition contacts
Unscrew the screw and nut holding the connection for the
transition resistors.
Unscrew the fixed transition contact. Mount new contacts.
Put the washers as shown in Fig. 15. Use new locking
washers. Tighten the screws, tightening torque approximately
10 Nm.
Mount the connection for the transition resistors. Tightening
torque approximately 10 Nm. Use new conical spring washers
and locking nuts.
The conicial end of the nut should be turned upwards.
4.8 Mounting the boards with transition resistors and
fixed contacts
To assemble the mechanism and the boards with transition
resistors and fixed contacts, do as follows:
When the boards are lowered, put one side of the mechanism
on an approximately 50 mm high piece of wood to make the
fixed and moving contacts free from each other (Fig. 23).
The boards should be fixed with new guide pins (4 x 30 mm,
spring-type straight pin slotted). Guide by inserting a 6 mm
mandrel into an adjacent screw hole. Put in and tighten
all screws. Secure the screws with new locking washers
(Fig. 18). The plain washers should be closest to the board.
Check that the linings of the fixed main contacts are aligned
with the linings of the moving main contacts. If not, loosen
the nuts slightly and adjust the fixed main contacts. Tighten
the nuts. Check (and adjust, if necessary) the alignment of
the transition contacts as described for the main contacts.
Tighten the screws and lock the locking washers.
Proceed with the other side of the diverter switch by first
operating it to the other side as described in section 3.9.
WARNING
Take care to avoid finger injuries when operating the
diverter switch.
Check (and adjust, if necessary) the diverter switch according
to section 3.9. Operate it and check that the contact
movement is correct. Remount the diverter switch into the
housing according to section 3.13.
Moving
main
contact
Fixed
main
contact
Piece of
wood
Fig. 23. Contact replacement, mounting the boards.