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Instruction Book
IB182017EN February 2017 www.eaton.com
5kV, 7.5kV, & 15kV DHP-VR
Replacement Circuit Breaker
To engage the secondary contacts on the 7.5kV or 15kV design
while the breaker is in the test position, unlatch the secondary
operating rod, and move it to the left until it points straight out from
the breaker. Push the rod manually to the rear until the secondaries
are initially engaged. Once initial engagement is achieved, hold the
operating rod firmly in that position with one hand, while grasping
the secondary engaging handle with the other hand. The secondary
engaging handle is located to the right of the operating rod, just
inside a rectangular hole. By pulling firmly on the engaging handle,
complete secondary engagement will be insured (Figure 5.11).
4.7 INTERLOCKS
WARNING
INTERLOCKS ARE PROTECTIVE DEVICES FOR PERSONNEL AND
EQUIPMENT. DO NOT BYPASS, MODIFY, OR MAKE INOPERATIVE ANY
INTERLOCKS. DOING SO COULD CAUSE DEATH, SERIOUS PERSONAL
INJURY, AND/OR PROPERTY DAMAGE.
There are several interlocks built into the VR-Series vacuum
replacement breakers. Each of these interlocks, though different
in form, duplicate or exceed the function of the original breaker’s
interlocks. These interlocks exist to safeguard personnel and
equipment. The basic premise behind the interlocking arrangement
on the vacuum replacement breaker is that the breaker must not be
inserted into or removed from a live circuit while the main contacts
are closed. Also considered in the interlocking is that the breaker
should pose no greater risk than necessary to the operator in or out
of the cell.
4.5.1 TIMING
The opening and closing times for the circuit breakers vary
depending upon the control voltage, power rating, environment and
test equipment. Differences in timing are expected between initial
factory measurements and field inspections. Circuit breaker timing
can be measured by service personnel using available equipment
before installation and in conjunction with regular maintenance
periods to assist in tracking the general health of the breaker. Typical
ranges as observed using nominal control voltages are listed in
Table 4.
Tablt 4. Timt Ptr Evtnt
Event
Milliseconds / Maximum
Closing Time
(From Initiation of Close Signal to Contact Make)
75
Opening Time
(Initiation of Trip Signal to Contact Break)
45
Reclosing Time
(Initiation of Trip Signal to Contact Make)
190
4.6 SECONDARY CONNECTION BLOCK
The breaker control wiring is arranged for drawout disconnecting
by means of a 15 point male plug arranged to connect to a female
receptacle mounted in the rear of the existing DHP cell. The
secondary contact plug is mounted on a movable bracket on the
left side of the breaker truck (Figures 4.6). This permits it to be
extended to the rear while the breaker is in the test position to make
with the stationary receptacle in the cell so that the control circuits
are completed. Control wiring terminates first at terminal blocks
mounted at the rear of the breaker truck, and continues from the
terminal blocks to the male contact plug.
Normally the secondary contacts are held stationary relative to the
breaker chassis. This is accomplished by a hinged joint in the hand
operating rod which acts on the edge of the lower front truck panel
to hold the assembly in position.
To engage the secondary contacts on the 5kV design while the
breaker is in the test position, lift the handle on the front left hand
side of the breaker chassis to a horizontal position. Once the rod is
pointing straight out from the breaker, push it manually to the rear
until the secondaries are initially engaged. At this point, the small
horizontal pin in the handle will have engaged two slots in the lever,
which is pivoted immediately above the handle. To insure complete
secondary engagement, push down firmly on the curved end of the
lever as far as it will go, using a foot or hand (Figure 5.10). When
using a foot, care should be taken not to bend the lever by using
excessive force.
Figurt 4.6. Malt Stcondary Contact Block (Exttndtd Position)
(5kV DHP-VR)
Figurt 4.7. Codt Platt (5kV DHP-VR)
Figurt 4.8. Codt Platt (15kV DHP-VR)
