Eaton 50DHP-VR, Instruction Handbook Manual

24

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)