1VAL050503-MB Rev B Replaces (1VAL057485-MB Rev. C) Oct 2013
20
C
ONTROL
S
CHEME
:
ADVAC™ circuit breakers are available with two control packages. The standard package (see Appendix D) includes
charge (MS), close (MC), and open (MO) functions, and 4a and 4b auxiliary contacts for customer use. The optional
package (see Appendix D) adds to the standard package 5a and 4b auxiliary contacts for customer use as well as an
optional second open/trip coil (MO2) and/or under voltage (MU) open/trip device if required. Refer to wiring diagrams in
Appendix D and Figure 3 on the next page.
1. Initial State
a. Closing Spring Discharged (33LSb Closed)
b. Breaker Open (52a Open/52b Closed)
2. Upon available control power
a. Secondary engaged
b. Motor charges through 33LSb
3. Closing spring charged
a. 33LSb opens (removing control power to motor)
b. Breaker ready to close
4. Electrical control pulse sent to close Breaker *
a. Current energizes Close Coil (MC) thru the closed blocking switch
Coil energizes releasing closing spring and closes breaker
–52a closes
– 52b opens
–33LSb closes
Motor charges through 33LSb, 33LSb Opens once closing spring is charged
Coil de-energizes with release of signal
5. Electrical control pulse sent to open circuit (note:
Current energizes 1st Trip/Open (MO1) or 2nd Trip/Open (MO2) or under voltage (MU)
Coil energizes releasing opening spring and opens breaker
–52a opens
– 52b closes
Coil de-energizes with release of signal
Breaker ready to perform O-C-O operation
MECHANISM AND OPERATION
*
Note: All open control signals must be zero
and Drawout Breakers’ must be in the test
or connected positions to engage the
Close Blocking switch located on the truck
in order for the Breaker to close.