Operating Mechanisms - ABB GSec/T1 Instructions For Installation, Operation And Maintenance

Switch-disconnector with earthing switch ST
3
LINE
IMS in closed position and ST
in open position.
Key
IMS = Switch-disconnector
ST = Earthing switch
Fig. 8

5.5. Operating mechanisms

Operating mechanism 1S is the "on exceeding dead-center
type". It uses a single spring to open and close the switch-
disconnector and to close the earthing switch/es. Operating
speed is independent of the operator.
Manual operating mechanism 2S is the stored energy type.
It uses two springs. The first closes the switch-disconnector
at an operating speed independent of the operator.
The second spring is loaded during the switch-disconnector
closing stage and is designed to both open the switch-
14
Key
2
4
1
5
OPEN
IMS and ST in open position.
disconnector (in the manual mode using the dedicated
pushbutton, or by fuse tripping or by means of the shunt
opening release) and close the earthing switches at an
operating speed independent of the operator.
Opening of the earthing switches takes place at operating
speeds independent of the operator.
1 Sealed metal enclosure
2 Upper connection of busbar compartment
3 Lower connection of busbar compartment
4 Upper insulating bushing of busbar compartment
5 Lower insulating bushing of busbar compartment
6 Fixed upper main contact
7 Fixed main contact of earthing switch
8 Fixed lower main contact of IMS/ST
9 Blade of switch-disconnectors
EARTH
ST in closed position and IMS in open posi-
tion.