S260-20-9
3
Figure 5.
Standard actuator.
Figure 6.
Status of mechanism with switch
closed.
Figure 8.
Status of mechanism during
closing operation.
Figure 9.
Standard actuator circuit diagram.
Figure 7.
Status of mechanism with switch
open.
DESCRIPTION OF
OPERATION
Standard Actuator
These switches are equipped with a
motor-operated actuator mechanism
(Figure 5) for remote closing. Remote
tripping is accomplished by energizing a
trip-open solenoid which unlatches a
spring-loaded operating mechanism to
open the main switch contacts. Subse-
quent closing is accomplished by oper-
ating the motor which loads the opening
springs, latches the operating mecha-
nism, and extends the opening spring
until it overtoggles and closes the main
switch contacts. Time of the closing
operation is approximately 10 seconds.
A mechanical schematic diagram
showing a single set of contacts con-
nected to a straight line motion linkage
and a stored energy actuator is used to
illustrate operating principles. With the
contacts closed (Figure 6), the opening
spring is held extended by a rigidly
latched toggle mechanism. When the
opening circuit is energized, the trip
solenoid breaks the latch to collapse
the toggle and open the main contacts
(Figure 7). Both springs are relaxed; the
contacts cannot be tripped closed acci-
dentally.
When the closing circuit is energized,
the motor operates to drive the crank-
ar m on the gear reduction which
extends the toggle until it latches and
extends both the opening and closing
springs (Figure 8). Further travel of the
crank ar m over toggles the closing
spring to close the switch and carry the
rigid toggle (and extended opening
springs) to the position shown in Figure
6, ready for another trip operation.
The selector switch provides orderly
transition from trip to close and from
close to trip. The selector switch is oper-
ated from the main shaft. When the
main contacts are closed the trip circuit
is enabled and the close circuit is dis-
abled. When the main switch contacts
are open the trip circuit is disabled and
the close circuit is enabled. Figure 9
shows the circuit diagram for the stan-
dard actuator.
