Eaton 150DHP-VR, Instruction Handbook Manual

22

Instruction Book    

IB182017EN   February 2017   www.eaton.com

5kV, 7.5kV, & 15kV DHP-VR

Replacement Circuit Breaker

a. Breaker open, closing springs discharged.
b. Breaker open, closing springs charged.
c. Breaker closed, closing springs discharged.
d. Breaker closed, closing springs charged.

The mechanism is a mechanically “trip-free” design. Trip-free is 

defined later in this section.
In normal operation the closing spring is charged by the spring 

charging motor, and the breaker is closed electrically by the 

switchgear control circuit signal to energize the spring release coil. 

Tripping is caused by energizing the trip coil through the control 

circuit.
For maintenance inspection purposes the closing springs can be 

charged manually by using the maintenance tool and the breaker can 

be closed and tripped by pushing the “Push to Close” and “Push to 

Open” buttons on the front panel.



 WARNING

KEEP HANDS AND FINGERS AWAY FROM 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 CRUSHING INJURY. DISCHARGE 

THE SPRINGS AND OPEN THE BREAKER BEFORE PERFORMING ANY 

MAINTENANCE, INSPECTION OR REPAIR ON THE BREAKER.

THE DESIGN OF THIS CIRCUIT BREAKER ALLOWS MECHANICAL CLOSING 

AND TRIPPING OF THE BREAKER WHILE IT IS IN THE “CONNECT” 

POSITION. HOWEVER, THE BREAKER SHOULD BE CLOSED MECHANICALLY 

ONLY IF THERE IS POSITIVE VERIFICATION THAT LOAD SIDE CONDITIONS 

PERMIT. IT IS RECOMMENDED THAT CLOSING THE BREAKER IN THE 

“CONNECT” POSITION ALWAYS BE DONE WITH THE CUBICLE DOOR 

CLOSED. FAILURE TO FOLLOW THESE DIRECTIONS MAY CAUSE DEATH, 

PERSONAL INJURY, OR PROPERTY DAMAGE.

ELECTRICAL TRIPPING CAN BE VERIFIED WHEN THE BREAKER IS IN THE 

“DISCONNECT / TEST” POSITION.

4.4.1   CLOSING SPRING CHARGING

Figure 4.15 shows schematic section views of the spring charging 

parts of the stored energy mechanism.
The major component of the mechanism is a cam shaft assembly 

which consists of a shaft to which are attached two closing spring 

cranks (one on each end), the closing cam, drive plate, and a free-

wheeling ratchet wheel.
The ratchet wheel (6) is actuated by an oscillating ratchet lever 

(12) and drive pawl (10) driven by the motor eccentric cam. As the 

ratchet wheel rotates, it pushes the drive plates which in turn rotate 

the closing spring cranks and the closing cam on the cam shaft. 

The motor will continue to run until the limit switch “LS” contact 

disconnects the motor.
The closing spring cranks have spring ends connected to them, 

which are in turn coupled to the closing springs. As the cranks 

rotate, the closing springs get charged.
The closing springs are completely charged, when the spring cranks 

go over dead center and the closing stop roller (9) comes against the 

spring release latch (1). The closing springs are now held in the fully 

charged position.
The closing springs may also be charged manually as follows: Insert 

the end of the maintenance tool into the manual charge socket 

opening and charge the closing springs by moving the handle up 

and down the full range of motion. When charging is complete the 

ratchet will no longer advance and the spring charged / discharged 

indicator displays “charged”. (Figure Set 3.3). Any further motion of 

the maintenance tool will not result into advance of charging.

4.4.2   CLOSING OPERATION

Figure 4.16 shows the positions of the closing cam and tripping 

linkage for four different operational states. In Figure 4.16.a the 

breaker is open and the closing springs are discharged. In this state, 

the trip latch is disengaged from the trip “D” shaft (unlatched). After 

the closing springs become charged, the trip latch snaps into the 

fully reset or latched position (Figure 4.16.b)
When the spring release clapper (Figure 4.15, Item 13) moves into 

the face of the spring release coil (electrically or manually), the upper 

portion of the clapper pushes the spring release latch (1) upward. 

When the spring release latch moves, the cam shaft assembly is 

free to rotate. The force of the closing cam (Figure 4.16.b, Item 5), 

moving the main link (2), rotating the pole shaft (4) (which charges 

the opening spring). This moves the three operating rods (3), closes 

the main contacts and charges the contact loading springs (not 

shown). The operational state immediately after the main contacts 

close but before the spring charging motor recharges the closing 

springs is illustrated in Figure 4.16.c. Interference of the trip “D” 

shaft with the trip latch prevents the linkage from collapsing, and 

holds the breaker closed.
Figure 4.16.d shows the breaker in the closed state after the closing 

springs have been recharged. The recharging of the spring rotates 

the closing cam one half turn. In this position the main link roller 

rides on the cylindrical portion of the cam, and the main link does 

not move out of position.

4.4.3   TRIPPING OPERATION

When the trip bar “D” shaft (Figure 4.16.b, Item 9) is turned by 

movement of the shunt trip clapper (11), the trip latch will slip past 

the straight cut portion of the trip bar shaft and will allow the banana 

link and main link roller to rise. The energy of the opening spring and 

contact loading springs is released to open the main contacts. The 

mechanism is in the state illustrated (Figure 4.16.b) after the breaker 

is tripped open.

4.4.4   TRIP-FREE OPERATION

When the manual trip button is held depressed, any attempt to close 

the breaker results in the closing springs discharging without any 

movement of the pole shaft or vacuum interrupter stem.

4.5   CONTROL SCHEMES

There are two basic control schemes for each series of Type VCP-WR 

breakers, one for DC control and one for AC control voltages (Figure 

4.5). Specific wiring schematics and diagrams are included with each 

breaker.
There may be different control voltages or more than one tripping 

element, but the principal mode of operation is as follows:
As soon as the control power is applied, the spring charging motor 

automatically starts charging the closing spring. When the springs 

are charged, the motor cut off LS1/bb switch turns the motor off. The 

breaker may be closed by making the control switch close (CS/C) 

contact. Automatically upon closing of the breaker, the motor starts 

charging the closing springs. The breaker may be tripped any time by 

making the control switch (CS/T) contacts.
Note the position switch (PS1) contact in the spring release circuit 

in the scheme. This contact remains made while the breaker is 

being racked between the TEST and CONNECTED positions for 

appropriately retrofitted breakers. Consequently, it prevents the 

breaker from closing automatically, even though the control close 

contact may have been made while the breaker is racked to the 

CONNECTED position.
When the CS/C contact is made, the  SR  closes the breaker. If 

the  CS/C contact is maintained after the breaker closes, the Y relay 

is picked up. The  Y/a contact seals in Y until CS/C is opened. The  

Y/b  contact opens the SR circuit, so that even though the breaker 

would subsequently open, it could not be reclosed before CS/C was 

released and remade. This is the anti-pump function.