Alstom FKG1X, Instruction Manual

Page: 70 / 274

Function description
FK 3-12 spring operating mechanisms
For circuit breakers
06.04.2011 48-020-212EN02
11/15
•
Cam disc 70.10 turns roller lever 70.11, which follows it, in the CLOSE
direction. The circuit breaker is closed via main shaft 70.12, operating
lever 70.18 and an attached linkage. At the end of the closing move-
ment, after a 60° rotation, specially designed cam disc 70.10 brings
main shaft 70.12 to a safe, low-impact stop against trip latch 70.16 via
a lever arm of roller lever 70.11. At the same time, cam disc 70.10 has
moved away from roller lever 70.11 and the circuit breaker can be trip-
ped.
•
In the course of the closing movement, trip spring 70.20 is charged via
trip chain 70.19.
•
The return-stop of pair of winding lever 71.32 keeps the fast gearing
stages from tracking the motion during the closing operation.
•
After closing shaft 70.09 has turned through approx. 180°, crank journal
70.29 passes through bottom dead point B. The Kinetic energy still
possessed by crank wheel 70.30 is returned to closing spring 70.25
(recovered) via chain 70.26. By virtue of this principle, the closing
movement is brought to a gentle, impact-free stop.
•
Control, indicating and interlock functions at the end of the closing
movement:
−
Auxiliary switch 70.21, which is coupled to main shaft 70.12 has
made the opening release coil circuit and broken the closing circuit.
The circuit breaker can be tripped electrically, and further actuation
of the closing coil is prevented.
−
A lever (not shown) controlled by main shaft 70.12 has disabled
closing latch 70.05, thus mechanically preventing any further release
of the closing system.
−
Circuit breaker position indicator 70.52 has turned to the CLOSED
position with main shaft 70.12.
−
Motor limit switch 70.24 actuated via motor limit switch actuating
cam 70.22, has made the motor circuit.
−
The closing coil circuit has been broken by one contact of motor limit
switch 70.24. Any further electrical actuation of the closing coil is
thus prevented
•
Spring position indicator 70.31 has simultaneously moved to «closing
spring discharged».
•
Circuit breaker and operating mechanism are in operating state 3.
Operating state 3: Transient
Motor Closing Opening
•
The circuit breaker is ready for tripping.