Siemens 8DA10 Series User Manual

Operation
154/214 Revision 11 • INSTALLATION AND OPERATING INSTRUCTIONS • 8DA10 • 861-9601.9
35 Interlocks
Switching devices may only be controlled and operated in logical dependence on the switch
position of other devices. Unpermissible switching operations must be blocked in order to:
• Provide full protection for the personnel.
• Prevent switchgear damages and power failures.
The interlocks are mainly of the mechanical type.
Mechanical interlocking The circuit-breaker and the three-position disconnector are mechanically interlocked against
each other.
Mechanical interlocking prevents,
• during manual operation, the circuit-breaker from being closed if the three-position
disconnector is not in a defined end position (CLOSED/OPEN/EARTHED).
• during manual operation, the circuit-breaker from being closed if the operating lever is
inserted.
• the three-position disconnector from being operated while the circuit-breaker is closed.
Interlocking conditions
Feeder and circuit-breaker panel of bus sectionalizer
Switching operation Switching operation only possible if Type
Disconnector CLOSED/OPEN circuit-breaker OPEN mechanical
earthing switch OPEN mechanical
Earthing switch CLOSED/OPEN circuit-breaker OPEN mechanical
disconnector OPEN mechanical
Circuit-breaker CLOSED disconnector or earthing switch not in intermediate
position (shutter open)
mechanical
Circuit-breaker OPEN not locked by a locking device mechanical
Additionally, electromechanical interlocks may be fitted for disconnectors and earthing switches or
for earthing switches.
Bus riser of bus sectionalizer unit / Disconnectable busbar connection / Top-mounted busbar sectionalizer
Switching operation Switching operation is only possible if Design
Disconnector CLOSED/OPEN associated circuit-breaker OPEN electromechanical
Earthing switch OPEN mechanical
Earthing switch CLOSED/OPEN associated circuit-breaker OPEN electromechanical
Disconnector OPEN mechanical
Additionally, electromechanical interlocks may be fitted for disconnectors and earthing switches or
for earthing switches.
Disconnectable busbar voltage transformer
Switching operation Switching operation is only possible if Design
Disconnector CLOSED/OPEN Earthing switch OPEN mechanical
Earthing switch CLOSED/OPEN Disconnector OPEN mechanical
Additionally, electromechanical interlocks may be fitted for disconnectors and earthing switches or
for earthing switches.
Make-proof busbar earthing switch
Switching operation Switching operation is only possible if Design
Earthing switch CLOSED/OPEN Opening for operating lever open mechanical

Siemens 8DA10 Series Specifications

General

Brand	Siemens
Model	8DA10 Series
Category	Circuit breakers
Language	English