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Instruction Book    IB182942EN   May 2019   www.eaton.com

DST-2-VR

+

VR-Series

+

 Replacement Circuit Breaker

 DANGER

FAILURE TO REPLACE THE VACUUM INTERRUPTER ASSEMBLY WHEN 

INDICATED BY THE CONTACT EROSION INDICATOR COULD CAUSE THE 

CIRCUIT BREAKER TO FAIL, LEADING TO DEATH, SEVERE PERSONAL 

INJURY, EQUIPMENT DAMAGE AND/OR IMPROPER OPERATION.

4.1.3   CONTACT WIPE AND STROKE

The circuit breaker mechanism provides a fixed amount of motion 

to the operating rods connected to the moving stem of the vacuum 

interrupter. The first portion of the motion, the stroke, is used to 

close the vacuum interrupter contacts; the remainder of that motion, 

the wipe, is used to further compress the pre-loaded wipe spring. 

Contact stroke and wipe are related; contact wipe is the indication 

of the force holding the vacuum interrupter contacts closed as well 

as the energy available to hammer the contacts open with sufficient 

speed for interruption. Stroke is the gap between the stationary and 

moving contact of the vacuum interrupter when the circuit breaker 

is open. As the stroke increases due to contact erosion inside the 

vacuum interrupter, the wipe decreases. Although these changes are 

taking place as operations accumulate on the vacuum interrupter, 

field adjustment of the wipe or stroke are not necessary during the 

lifetime of the vacuum interrupter. 

 WARNING

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.

4.2   LINE AND LOAD CONDUCTOR ASSEMBLIES

Multiple finger type primary disconnecting contacts at the ends of 

the conductors provide means for connecting and disconnecting 

the circuit breaker to the bus terminals in the circuit breaker 

compartment of the metal-clad switchgear.

4.3   STORED ENERGY MECHANISM

The spring-type stored energy operating mechanism is mounted 

on the circuit breaker frame and in the front of the circuit breaker. 

Manual closing and opening controls are at the front cover (Figure 

Set 3.3). They are accessible while the circuit breaker is in any of its 

basic installation positions. (See Section 5 in this manual)
The mechanism stores the closing energy by charging the closing 

springs. Spring charging is automatically accomplished when control 

power is applied to the circuit breaker secondary disconnect contact. 

When released, the stored energy closes the circuit breaker, charges 

the wipe and resets the opening springs. The mechanism may rest 

in any one of the four positions shown in Figure 4.8 as follows:
a. Circuit Breaker open, closing springs discharged.
b. Circuit Breaker open, closing springs charged.
c. Circuit Breaker closed, closing springs discharged.
d. Circuit Breaker closed, closing springs charged.

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

defined in Section 4.3.4 (Trip-Free Operation).
In normal operation the closing spring is charged by the spring 

charging motor, and the circuit 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 circuit 

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

and “Push to Open” operators on the front cover.

 DANGER

KEEP HANDS AND FINGERS AWAY FROM CIRCUIT BREAKER’S INTERNAL 

PARTS WHILE THE CIRCUIT BREAKER CONTACTS ARE CLOSED OR THE 

CLOSING SPRINGS ARE CHARGED. THE CIRCUIT BREAKER CONTACTS 

MAY OPEN OR THE CLOSING SPRINGS DISCHARGE CAUSING CRUSHING 

INJURY. DISCHARGE THE SPRINGS AND OPEN THE CIRCUIT BREAKER 

BEFORE PERFORMING ANY MAINTENANCE, INSPECTION OR REPAIR ON 

THE CIRCUIT BREAKER.

THE DESIGN OF THIS CIRCUIT BREAKER ALLOWS MECHANICAL CLOSING 

AND TRIPPING OF THE CIRCUIT BREAKER WHILE IT IS IN THE ‘CONNECT’ 

POSITION. HOWEVER, THE CIRCUIT BREAKER SHOULD BE CLOSED 

MECHANICALLY ONLY IF THERE IS POSITIVE VERIFICATION THAT LOAD 

SIDE CONDITIONS PERMIT. IT IS RECOMMENDED THAT CLOSING THE 

CIRCUIT BREAKER IN THE ‘CONNECT’ POSITION ALWAYS BE DONE WITH 

THE CUBICLE DOOR CLOSED. FAILURE TO FOLLOW THESE DIRECTIONS 

MAY CAUSE DEATH, SEVERE PERSONAL INJURY, EQUIPMENT DAMAGE 

AND/OR IMPROPER OPERATION.

ELECTRICAL TRIPPING CAN BE VERIFIED WHEN THE CIRCUIT BREAKER IS 

IN THE ‘DISCONNECT / TEST’ POSITION.

4.3.1   CLOSING SPRING CHARGING

Figure 4.7 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.

4.3.2   CLOSING OPERATION

Figure 4.8 shows the positions of the closing cam and tripping 

linkage for four different operational states. In Figure 4.8.a the 

circuit breaker is open and the closing springs are not charged. In 

this state, the trip latch (8) is disengaged from the trip “D” shaft (9) 

(unlatched). After the closing springs become charged, the trip latch 

snaps into the fully reset or latched position (Figure 4.8.b)
When the spring release clapper (Figure 4.7, Item 13) moves into the 

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

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

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

free to rotate. The force of the closing cam (Figure 4.8.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 4.8.c. Interference of the trip “D” shaft 

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

the circuit breaker closed.

Summary of Contents for DST-2-15-VR+

Page 1: ...Instruction Book IB182942EN DST 2 VR VR Series Replacement Circuit Breaker DST 2 15 VR 500 2000A Shown May 2019 Supersedes July 2018 Effective...

Page 2: ...ions of this equipment do not purport to be covered by these instructions If further information is desired by purchaser regarding his particular installation operation or maintenance of particular eq...

Page 3: ...ERATION CHECK 21 5 4 VACUUM INTERRUPTER INTEGRITY 21 5 5 LOW FREQUENCY WITHSTAND TEST INSULATION CHECK 21 5 6 CONTACT EROSION AND WIPE 21 5 7 PRIMARY CIRCUIT RESISTANCE 21 5 8 ELECTRICAL OPERATIONS CH...

Page 4: ...portant that this installation and maintenance instruction booklet be read and followed closely to achieve optimum performance and a long useful circuit breaker life in its application 1 1 VISUAL INST...

Page 5: ...kV Peak I kA RMS KI kA RMS kA RMS Peak DST 2 5 250 DST 2 5 VR 250 4 76 250 1200 2000 1 24 19 60 29 36 58 97 DST 2 5 250 DST 2 5 VR 41 b c 4 76 N A 1200 200 1 0 19 60 41 41 78 132 DST 2 7 5 500 DST 2 7...

Page 6: ...acement Circuit Breaker Table 2 DST 2 VR Dimensions Circuit Breaker Type Existing Circuit Breaker Rated Continuous Current at 60 Hz Amps A B C D E F DST 2 15 VR 1200 2000 65 38 25 75 7 88 34 18 11 00...

Page 7: ...st coupler engaged Failure to disconnect the test coupler could result in an electrical shock leading to death severe personal injury equipment damage and or improper operation Do not work on a closed...

Page 8: ...and other components If damaged or loss is detected file claims immediately with the carrier and notify an Eaton representative Tools and Accessories Maintenance Tool Style 94C9506G01 This tool is use...

Page 9: ...it in to storage The circuit breaker is shipped with its contacts open and closing springs discharged The indicators on the front cover should confirm this Insert the end of the maintenance tool into...

Page 10: ...VR Front External View 1 Lock Out Tag Out 6 Manual Charging Socket 11 Interlock Pedal 2 Levering Point 7 Spring Charged Discharged Indicator 12 Manual Motor Cut Off Switch 3 Terminal Block Access 8 Op...

Page 11: ...com DST 2 VR VR Series Replacement Circuit Breaker Figure 3 3 b Rear External View of DST 2 15 VR Rear External View 1 Lifting Points 4 Anti Rotation Self Adjuster Optional 2 Secondary Disconnects 5...

Page 12: ...DST 2 5 VR Front External View 1 Push to Close Button 5 Main Contact Status Indicator 9 Push To Open Button 2 Lock Out Tag Out 6 Manual Charging Socket 10 Interlock Pedal 3 Levering Point Tow Hitch 7...

Page 13: ...EN May 2019 www eaton com DST 2 VR VR Series Replacement Circuit Breaker Figure 3 3 d Rear External View of DST 2 5 VR Rear External View 1 Lifting Points 4 Ground Contact 2 Secondary Disconnects 3 Pr...

Page 14: ...is assembled at the factory as a unit to assure correct dimensional relationships between working components Three interrupter assemblies are used per circuit breaker Each vacuum interrupter assembly...

Page 15: ...ER CONTACTS ARE CLOSED OR THE CLOSING SPRINGS ARE CHARGED THE CIRCUIT BREAKER CONTACTS MAY OPEN OR THE CLOSING SPRINGS DISCHARGE CAUSING CRUSHING INJURY DISCHARGE THE SPRINGS AND OPEN THE CIRCUIT BREA...

Page 16: ...This is the anti pump function 4 4 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 ti...

Page 17: ...est and Connect positions OPERATION C and NO C and NC C and NO C and NO C and NC C and NO Brown Switch Black Switch Black Switch Brown Switch SWITCH TERMINAL LS1 bb LS2 aa LS2 bb LC PS1 PS2 Circuit Br...

Page 18: ...ring system tripping and spring release interlocks perform the following a Set the breaker mechanically trip free during the first 4 inches of travel into the cell and whenever the breaker receives a...

Page 19: ...over Removed VR Series Circuit Breaker Element Mechanism 1 LH Closing Spring 5 Spring Release Assembly 9 Manual Charge Socket 2 Latch Check Switch To Rear of Motor Cutoff Switch 6 Shunt Trip Assembly...

Page 20: ...aker Closed Springs Charged 2 1 3 4 5 6 7 8 9 10 11 12 13 14 Closing Cam and Trip Linkage 1 Spring Release Close Latch 6 Ratchet Wheel 11 Anti Close Interlock 2 Pole Shaft 7 Spring Crank 12 Motor Ratc...

Page 21: ...2 Main Link 6 Cam Shaft 10 Trip Latch Reset Spring 3 Operating Rod 7 Banana Link 11 Shunt Trip Lever 4 Pole Shaft 8 Trip latch 12 Shunt Trip Coil 4 1 2 3 5 6 7 8 9 10 11 12 4 8 a Circuit Breaker Open...

Page 22: ...cell containing an MOC until after the switch has been properly adjusted WARNING MEASUREMENTS AND ADJUSTMENTS SHOULD NEVER BE ATTEMPTED IN AN ENERGIZED STRUCTURE IF THE STRUCTURE CANNOT BE DE ENERGIZ...

Page 23: ...S REMOVE THE MAINTENANCE TOOL AFTER CHARGING THE SPRING FAILURE TO REMOVE THE MAINTENANCE TOOL FROM THE BREAKER COULD CAUSE INJURY TO PERSONNEL AND OR EQUIPMENT DAMAGE IF THE BREAKER WAS TO CLOSE Clos...

Page 24: ...The test position can be verified by the inability to move the breaker in or out the Interlock Pedal is in the up position and the cell label test is visible on the floor of the cell in front of the...

Page 25: ...onnect position can be verified by the inability to move the breaker in or out the Interlock Pedal is up and has released the trip mechanism and the cell label operating is visible on the floor of the...

Page 26: ...s DISCHARGED and that the main contact status indicator reads OPEN Manually trip close and trip the breaker as needed to obtain this status Note N The motor cutoff switch is located on the lower cover...

Page 27: ...so that the circuit breaker could be closed It must be returned to the fully withdrawn condition prior to insertion in the circuit breaker compartment b From the withdrawn position align the center g...

Page 28: ...al of the circuit breaker Note N For Canadian versions with separate disconnect and test positions it will stop at the test position Electrical and mechanical tests of the circuit breaker can be perfo...

Page 29: ...and retest or replace Insulation Integrity Main circuit to ground Withstand 15kV 60Hz for 1 Minute 5kV Rating Hi pot Tester Clean and retest or replace Control circuit to ground Charging Motor discon...

Page 30: ...ommended that the equipment be capable of delivering 25 milliamperes for one minute The current delivery capability of 25 mA ac applies when all three vacuum interrupters are tested in parallel If ind...

Page 31: ...essed in micro ohms Repeat for the remaining two poles The resistance should not exceed the factory test levels more than 200 as stated in IEEE C37 09 Factory test levels are recorded on the circuit b...

Page 32: ...ol Mounting Testing Locations by Circuit Breaker Type CIRCUIT BREAKER DESIGNATION APPROXIMATE MECHANISM CHASSIS WIDTH INCH LOWER MOUNTING HOLE LOWER MOUNTING HOLE MARKER PLACEMENT HOLE VR Series 18 A1...

Page 33: ...sheet of paper that can be kept as a record of the test Record the date of the test person conducting the test circuit breaker serial number and the operations counter on the tape or paper Figures 6...

Page 34: ...arker Interface Cam Marker CloSure Tool TM 15 O 15 O Figure 6 13 Determining the Distance Traveled Figure 6 14 Illustrative Testing Tape Sample Figure 6 12 Evaluate the CloSure Performance Date of Bre...

Page 35: ...nt requires maintenance only once every ten years or ten thousand operations which ever comes first After a ten year service interval or when ten thousand operations have been reached contact your loc...

Page 36: ...urned Motor Cut Off Contacts open or burned Trip Coil Assembly Clapper fails to reset Closing sound but no close Pole Shaft Not open fully Trip Latch Reset Spring Damaged or missing Trip Bar D Shaft F...

Page 37: ...WITCH Circuit Breaker Auxiliary Switch 94C9525G13 5 POSITION SWITCH Circuit Breaker Position Switch PS1 94C9525H06 6 POSITION SWITCH Circuit Breaker Position Switch PS2 94C9525H07 7 LATCH CHECK SWITCH...

Page 38: ...ulevard Cleveland OH 44122 United States Eaton com 2019 Eaton All Rights Reserved Printed in USA Publication No IB182942EN May 2019 Eaton is a registered trademark All trademarks are property of their...

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