Rockwell Automation 1502 Medium Voltage Contactor, 800A (Series D and E) - Manual (Page 7)

Contactor Product Description 1-3
1502-UM051E-EN-P – June 2013
Contactor Operation
The standard electrically held contactor consists of three vacuum bottles oper-
ated by an electromagnet assembly through a mechanical linkage (See Figure
1.3).
Electro-Mechanical Control (Series D)
• When the control circuit is energized, current flows through both a closing coil
and hold-in coil, creating an electromagnet.
• This electromagnet pulls the armature plate towards the coil cores which also
rotates the actuator shaft.
• The actuator plate, in turn, pushes the insulator and movable shaft up, closing
the contacts inside the vacuum bottle.
• The control circuit economizing/auxiliary contacts, located on the left side of
the contactor, change state once the contactor closes.
• The current that is energizing the closing coil is then switched off. The contac-
tor remains closed by the hold-in coil only.
• The contactor is opened by de-energizing the hold-in coil.
The mechanical latch version of the contactor operates basically the same way
with the following exceptions:
• Both coils are de-energized upon closing of the contactor, and the armature is
held in the closed position by a spring-loaded latching mechanism.
• The contactor is opened by energizing a trip coil which pulls the latch away
from the armature, or by engaging a manual trip mechanism via a pushbutton
located on the front of the medium voltage door (see Figure 1.4).
Note: External control relays and a rectification circuit are used to control the
standard DC closing and hold-in coils on the contactor.