GE Industrial Solutions BreakMaster Load Interrupter Switch - Manual (Page 19)

18
BreakMaster Load Interrupter Switch
Figure 19
Typical Control Diagram
The device numbers used in this diagram are from the American National Institute and descriptions are are follow:
5
Stopping Device
89 Line Switch
89X Closing Relay
89Y Opening Relay
89/CL Auxiliary Switch on 89 (Closed when 89 is Open)
89/OP Auxiliary Switch on 89 (Open when 89 is Open)
SOL Clutch Solenoid
A Motor Armature
FS Fuse
D1-D4 Diode Bridge (Omitted when control power is DC)
Movement of the solenoid (SOL) compresses spring (SP) and engages clutch (CL). Motor rotates sprocket (SRA)
which through its chain drive (CHA) rotates the Load Interrupter Switch drive shaft to close the load break switch.
When the Load Interrupter Switch drive shaft rotates over center, auxiliary switch (89OP/CL) reverses its position,
de-energizing the closing relay (89X) to:
1. Stop the motor (A)
2. De-energize solenoid (SOL)
3. Set-up Load Interrupter Switch opening circuits
De-energizing solenoid (SOL) releases compressed springs’ (SP) energy to disengage the clutch (CL).
Disengagement of the clutch is to prevent the motor armature inertia from overdriving the Load Interrupter
Switch drive shaft and causing mechanical damage.
To open the Load Interrupter Switch, apply a signal to the 89Y coil. The Load Interrupter Switch will open in the
same manner as described above and set-up the control circuit for a closing signal.
To reverse from either a closing or opening operation, the polarity of the motor armature is reversed.
Decoupling test feature, if required to test motor drive system without moving main switchblades, can be
accomplished by inserting a control switch in series with the solenoid (SOL) or simply removing decoupling
jumper. (See Figure 19.)
CAUTION
Do not leave equipment in decoupled mode. If left in that mode, a signal to operate
will continuously drive motor without operating Load Interrupter Switch switch blades.
!