Rockwell Automation 1502 Medium Voltage 400A Contactor - Series E - Manual (Page 7)

Rockwell Automation Publication 1502-UM052H-EN-P - June 2013 7
Product Description Chapter 1
Figure 3 - Vacuum Contactor Operation
Mechanically Latched
Contactor Operation The mechanically latched contactor operates in much the same way as the
electrically held (
Figure 3 ) with only a few exceptions.
IntelliVAC and IntelliVAC Plus Control
• Once the contactor is closed, a spring-loaded mechanism moves a roller
against the armature plate to hold it against the electromagnetic core.
• The contactor can be opened electrically by energizing a trip coil (via
IntelliVAC or IntelliVAC Plus ‘open’ [TCO] output) which pulls the
latch away from the armature, or by a push button mounted on the power
cell door that mechanically releases the contactor.
Electromechanical Control
• When the control circuit is energized, the current creates an electromagnet
in the closing coil.
• The electromagnet pulls the armature plate towards the coils’ core,
rotating the shaft and causing the actuator plate to move upwards.
• As the actuator plate moves, it pushes the insulator and movable shaft up,
closing the contacts in the vacuum bottle.
• Once the contactor is closed, a spring-loaded mechanism moves a roller
against the armature plate to hold it against the electromagnetic core.
• The control circuit economizing auxiliary contact, on the left side of the
contactor, changes from the normally closed state to the normally open
state as the contactor closes. This de-energizes the relay that controls the
closing coils.
Insulator
Armature Plate & Shaft
Auxiliary Actuator
Armature Stop Bracket
Control Wire Plug
Line Terminal
Vacuum Bottle
Load Terminal
Flexible Bus
Return Spring
Actuator Plate
Gap Adjustment Screw
Magnet/Coil Assembly
C.P.T. Fuse Clip
Contactor Open Contactor Closed