Eaton 50 VCP-TR16, Instructions For The Use

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Instruction Book
Effective: November 2017 Page 35
IB131016EN For more information visit: www.Eaton.com
vacuum interrupters. The rear covers do not have to be
removed to take the contact wipe measurements.
Measurements are taken at the very bottom of each pole
unit as described in paragraph 6-5.1 (Figure
3-8).
CAUTION
THERE IS NO PROVISION FOR IN SERVICE
ADJUSTMENTS OF CONTACT WIPE AND STROKE.
ALL SUCH ADJUSTMENTS ARE FACTORY SET
AND SHOULD NOT BE ATTEMPTED IN THE FIELD.
5-3 STORED ENERGY MECHANISM
CAUTION
KEEP HANDS AND FINGERS AWAY FROM THE
BREAKER'S INTERNAL PARTS WHILE THE
BREAKER CONTACTS ARE CLOSED OR THE
CLOSING SPRINGS ARE CHARGED. THE
BREAKER CONTACTS MAY OPEN OR THE
CLOSING SPRINGS DISCHARGE CAUSING
INJURY. DISCHARGE THE SPRINGS AND OPEN
THE BREAKER BEFORE PERFORMING ANY
MAINTENANCE, INSPECTION OR REPAIR.
The two step stored energy mechanism is arranged
vertically in front of the circuit breakers. It is easily
accessed by removing four cover screws and the front
cover (Figures
3-10, 5-2 and 5-3). The mechanism is
based on a proven cam and spring design.
Figure 5-6 Breaker Closing Springs Being Manually
Charged
The stored energy mechanism uses stored potential
energy to close the circuit breaker. Sufficient energy to
open the circuit breaker becomes available after a
closing operation. After closing, springs can be
recharged permitting the following operating sequence:
open - close - open (O-CO). This feature provides a high
degree of service continuity.
Manual controls are front accessible. Motion to close and
open the interrupter contacts is provided through
operating rods connecting the mechanism to the
interrupter assemblies.
5-3.1 MANUAL OPERATION
A standard circuit breaker is a manually operated
breaker with one shunt trip. The closing springs can
only be charged manually. To manually charge the
springs, insert one finger in the recess behind the
charging handle and pull out. This permits a hand to
grasp the handle and begin charging (Figure
5-6). It
takes a number of down-ward strokes on the charging
handle to complete the manual charging process. Keep
in mind that it is possible to manually recharge the
springs immediately after closing the circuit breaker and
before it has been tripped open.
Manually operated circuit breakers are normally closed
and opened by hand using the manual "ON" and manual
"OFF" buttons respectively. These buttons are
conveniently located on the front of the circuit breaker
(Figure
3-10). Performing either operation is
accomplished by pressing and releasing the appropriate
button. Access to these pushbuttons can be limited by
the use of an option-al, padlockable cover. In addition,
complete access to the "ON" pushbutton can be
prevented with an optional prevent close cover. The
status of the springs and the primary contacts is always
indicated in an indicator window just above the
pushbuttons. In addition, the standard shunt trip can
also be used to electrically trip (open) the circuit
breaker.
Other optional electrically operated devices are available
to automatically close or trip manually operated circuit
breakers. An electrical spring release is available to
close a manually operated circuit breaker. Two other
optional devices, a second shunt trip or an undervoltage
release, can be used to automatically trip (open) a
manually operated circuit breaker. All of these optional
devices can be installed in the field. For more details,
refer to paragraph 5-5.1 later in this section.
Manually operated circuit breakers are pre-wired to
accept the addition of an electrical motor operator. An
electrical operator is used to automatically charge the
closing springs. Refer to paragraph 5-3.2 for more
details.