Siemens 8DA10 Series - Three-Position Disconnector; Function

Description
18/214 Revision 11 • INSTALLATION AND OPERATING INSTRUCTIONS • 8DA10 • 861-9601.9
8 Three-position disconnector
Function The three-position disconnector combines the functions of a disconnector and an earthing
switch. The three-position disconnector is designed for no-load operation only.
Fig. 6: Three-position disconnector with
busbar and bushing
①
Fixed contact, busbar
②
Busbar housing
③
Busbar
④
Busbar support
⑤
Fixed contact, earth
⑥
Bushing
⑦
Moving contact in
READY-TO-EARTH/EARTHED position
⑧
Moving contact in CLOSED position
⑨
Moving contact in OPEN position
Switch positions Position indicator Basic scheme
OPEN - Three-position disconnector OPEN
- Circuit-breaker OPEN
CLOSED - Three-position disconnector CLOSED
- Circuit-breaker CLOSED
READY-TO-EARTH - Three-position disconnector READY-TO-EARTH
- Circuit-breaker OPEN
EARTHED - Three-position disconnector EARTHED
- Circuit-breaker CLOSED