Siemens SDV-4A Instruction Manual

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15.5kV, 25.8kV and 27.6kV Power Circuit Breaker

Type SDV-4A

Instructions

Installation Operation Maintenance

SGIM-3788F

Hazardous voltages and high-speed moving parts.

Will cause death, serious injury or property damage.

Always de-energize and ground the equipment before maintenance. Read and understand this instruction manual before using equipment.

Maintenance should be performed only by qualified personnel. Use only Siemens parts in the repair of the equipment. Do not allow tampering with the equipment. Follow all safety instructions contained herein.

IMPORTANT

The information contained herein is general in nature and not intended for specific application purposes. It does not relieve the user of responsibility to use sound practices in application, installation, operation, and maintenance of the equipment purchased. Siemens reserves the right to make changes in the specifications shown herein or to make improvements at any time without notice or obligations. Should a conflict arise between the general information contained in this publication and the contents of drawings or supplementary material or both, the latter shall take precedence.

QUALIFIED PERSON

For the purpose of this manual a qualified person is one who is familiar with the installation, construction or operation of the equipment and the hazards involved. In addition, this person has the following qualifications: (a) is trained and authorized to de-energize, clear, ground, and tag cir-

cuits and equipment in accordance with established safety practices.

(b) is trained in the proper care and use of protective equipment such as

rubber gloves, hard hat, safety glasses or face shields, flash clothing, etc., in accordance with established safety practices.

NOTE

These instructions do not purport to cover all details or variations in equipment, nor to provide for every possible contingency to be met in connection with installation, operation, or maintenance. Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to the local sales office. The contents of this instruction manual shall not become part of or modify any prior or existing agreement, commitment or relationship. The sales contract contains the entire obligation of Siemens Power Transmission & Distribution Inc. The warranty contained in the contract between the parties is the sole warranty of Siemens Power Transmission & Distribution Inc. Any statements contained herein do not create new warranties or modify the existing warranty.

15.5kV, 25.8kV and 27.6kV Power Circuit Breaker

Table of Contents

Introduction and Safety ....................................................... 2

Introduction ............................................................................. 2

Qualified Person ...................................................................... 2

Signal Words ........................................................................... 2

Hazardous Procedures ............................................................ 2

Field Service Operation ........................................................... 2

General Description .............................................................. 3

Introduction ............................................................................. 3

Scope ...................................................................................... 3

General Description ................................................................ 3

Receiving, Handling & Storage ............................................ 4

Receiving ................................................................................ 4

Inspection ............................................................................... 4

Shipping Damage Claims ........................................................ 4

Lifting and Moving .................................................................. 5

Lifting Power Circuit Breaker with Crane ................................ 5

Storage .................................................................................... 5

Installation ............................................................................. 6

Location .................................................................................. 6

Preparation for Installation ...................................................... 6

“X” Bracing Installation Instructions

(for High Seismic Applications Only) ............................... 6

Foundation-General Requirements ......................................... 7

Electrical Connections .......................................................... 8

Primary Lead Connections ...................................................... 8

Ground Connections ............................................................... 8

Secondary Control Wiring ....................................................... 8

Instrument Transformers ..................................................... 9

Current Transformers .............................................................. 9

Installation Checks and Initial Functional Tests ............... 10

Introduction ........................................................................... 10

Inspections, Checks, And Tests Without Control Power ...... 10

Spring Discharge Check ........................................................ 10

Physical Inspections .............................................................. 11

Manual Spring Charging Check ............................................. 11

As-Found and Vacuum Check Tests ...................................... 11

Automatic Spring Charging Check ........................................ 11

Final Mechanical Inspection and

Testing Without Control Power ..................................... 11

Inspection ............................................................................. 11

Testing ................................................................................... 12

Interrupter/Operator Description ...................................... 13

Introduction ........................................................................... 13

Vacuum Interrupters ............................................................. 13

Stored Energy Operating Mechanism ................................... 13

Modes Of Operation - Discussion ......................................... 14

Spring Charging Mode .......................................................... 14

Closing Mode ........................................................................ 15

Trip Free Mode ...................................................................... 15

Opening Mode ...................................................................... 15

Rapid Auto-Reclosing Mode ................................................. 15

Closing And Tripping Springs ................................................ 15

Trip Free Operation ............................................................... 16

Damper ................................................................................. 16

Manual Spring Charging ........................................................ 16

Spring Charging Motor .......................................................... 17

Close Solenoid, Trip Solenoid and Anti-Pump Relay ............. 17

Auxiliary Switch ..................................................................... 17

Limit Switches ...................................................................... 17

Standard Schematic Diagrams .............................................. 17

Capacitor Trip Device (Optional) ............................................ 18

Maintenance ........................................................................ 21

Inspection and Maintenance Intervals .................................. 21

Recommended Hand Tools ................................................... 21

Recommended Maintenance and Lubrication ...................... 21

De-energize the Circuit Breaker ............................................ 22

Checks Of Primary Power Path ............................................ 22

Cleanliness Check ................................................................. 22

Checks of the Stored Energy Operator Mechanism ............. 23

Maintenance and Lubrication ................................................ 23

Fastener Check ..................................................................... 23

Manual Spring Charging And Contact Erosion Checks ......... 23

Vacuum Interrupter Stroke Check ......................................... 24

Damper Assembly Check ..................................................... 25

Electrical Control Checks ...................................................... 25

Check Of The Wiring And Terminals ..................................... 25

Automatic Spring Charging Check —

Control Power Required................................................ 25

Electrical Close And Trip Check —

Control Power Required................................................ 26

Checks Of Spring Charging Motor ........................................ 26

High Potential Tests .............................................................. 26

Vacuum Integrity Check ........................................................ 26

High Potential Test Voltages ................................................. 26

Vacuum Integrity Test Procedure .......................................... 27

As-Found Insulation and Contact Resistance Tests .............. 27

Insulation and Contact Resistance Test Equipment .............. 27

Insulation and Contact Resistance Test Procedure ............... 27

Inspection And Cleaning Of Breaker Insulation .................... 28

Functional Tests .................................................................... 28

Relays and Instruments ........................................................ 28

Equipment Surfaces .............................................................. 28

Operator Adjustments ........................................................ 29

Spring Charging Adjustment ................................................. 29

Spring Release Latch “Bite” Adjustment ............................. 30

Overhaul .............................................................................. 31

Introduction ........................................................................... 31

Circuit Breaker Overhaul ....................................................... 31

Replacement At Overhaul ..................................................... 31

Replacement Of Closing Springs .......................................... 31

Replacement Of Opening Spring .......................................... 32

Replacement Of Closing and Tripping Solenoids

(Devices 52SRC and 52T) ............................................. 32

Replacement of Anti-Pump Relay (Device 52Y) .................... 32

Replacement of the Auxiliary Switch .................................... 32

Replacement of Motor Cutoff Switch (Device LS1)

and Spring Charged Switch (LS2) ................................. 33

Replacement of Trip Latch Reset Check Switch

(Device LS3) .................................................................. 33

Replacement of Damper Assembly ...................................... 34

Replacement of Spring Charging Motor (Device 88) ............ 34

Replacement of Vacuum Interrupters ................................... 34

Index of Figures and Tables .................................................. 34

Recommended Hand Tools ................................................... 34

Preparation ............................................................................ 35

Vacuum Interrupter Removal ................................................ 35

Vacuum Interrupter Replacement ......................................... 35

Periodic Maintenance and Lubrication Tasks ................... 39

Troubleshooting .................................................................. 40

Ordering Replacement Parts ................................................. 42

Appendix .............................................................................. 43

Cover 2074-98

Introduction and Safety

Introduction

The SDV (generic family name for SDV-4A) vacuum breakers are designed to meet all applicable ANSI, NEMA, and IEEE standards. Successful application and operation of this equipment depends as much upon proper installation and maintenance by the user as it does upon the careful design and fabrication by Siemens.

The purpose of this instruction manual is to assist the user in developing safe and efficient procedures for the installation, maintenance and use of the equipment.

Contact the nearest Siemens representative if any additional information is desired.

Hazardous voltages and high-speed moving parts.

Will cause death, serious injury or property damage.

To avoid electrical shock, burns and entanglement in moving parts this equipment must be installed, operated and maintained only by qualified persons thoroughly familiar with the equipment, instruction manuals and drawings. Read and understand this instruction manual before using equipment.

Qualified Person

For the purpose of this manual a Qualified Person is one who is familiar with the installation, construction or operation of the equipment and the hazards involved. In addition, this person has the following qualifications:

Caution - indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.

Caution (without safety alert symbol) - indicates a potentially hazardous situation which, if not avoided, may result in property damage.

Hazardous Procedures

In addition to other procedures described in this manual as dangerous, user personnel must adhere to the following:

1. Always work only on a de-energized breaker. The breaker should be isolated, grounded, and have all control power removed before performing any tests, maintenance or repair.

2. Always perform maintenance on the breaker after the spring-charged mechanisms are discharged (except for test of the charging mechanisms). Check to be certain that the indicator flags read OPEN and DISCHARGED.

3. Always let an interlock device or safety mechanism perform its function without forcing or defeating the device.

Field Service Operation

Siemens can provide competent, well-trained Field Service Representatives to provide technical guidance and advisory assistance for the installation, overhaul, repair and maintenance of Siemens equipment, processes and systems. Contact regional service centers, sales offices or the factory for details, or telephone Siemens Field Service at 1-877-742-3309.

• Training and authorization to energize, de-energize, clear, ground and tag circuits and equipment in accordance with established safety practices.

• Training in the proper care and use of protective equipment such as rubber gloves, hard hat, safety glasses, face shields, flash clothing, etc., in accordance with established safety procedures.

• Training in rendering first aid.

Signal Words

The signal words “Danger”, “Warning” and “Caution” used in this manual indicate the degree of hazard that may be encountered by the user. These words are defined as:

Danger - Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.

Warning - Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

General Description

The instructions included in this manual are provided to aid you in obtaining longer and more economical service from your Siemens Circuit Breakers. For proper installation and operation, this information should be distributed to your operators, engineers and maintenance personnel.

By carefully following these instructions, difficulties should be avoided. However, the instructions are not intended to cover all details of variations that may be encountered in connection with the installation, operation and maintenance of this equipment.

Should additional information be desired, including replacement instruction books, contact your Siemens representative.

Scope

These instructions cover the installation, operation and maintenance of Siemens type SDV power circuit breakers using vacuum interrupters. The equipment described in this manual consists of free standing outdoor power circuit breakers for application up to 27.6kV. A typical breaker is shown in Figure 1. All diagrams, descriptions and instructions apply to all above types and designs unless noted otherwise.

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Figure 1. Typical Power Circuit Breaker, Type SDV-4A.

Introduction

The successful performance and application of Power Circuit Breakers depends as much on proper installation, maintenance and correct application as it does on good design and careful manufacture .

Siemens Type SDV outdoor power circuit breakers are precision built units designed to function efficiently under normal operating conditions. They are designed and manufactured to operate within the limits established in the ANSI C37 and NEMA standards for Power Circuit Breakers. Performance requirements of these standards have been met or exceeded by these designs. Specific Standards which apply include:

Standard construction details of the circuit breaker are given in the appropriate sections. Special mechanical and electrical devices, furnished in accordance with purchase order requirements, are covered by supplementary instructions submitted with this instruction manual.

The equipment furnished has been designed to operate in a system having the circuit capacity specified by the purchaser. If for any reason the equipment is used in a different system, or if the short-circuit capacity of the system is increased, the momentary rating and interrupting capacity of the circuit breaker must be checked. Failure on the part of the user to receive approval of intended changes from Siemens may cause voiding the warranty.

General Description

The power circuit breaker described in this manual is the AC high-voltage circuit breaker type, as defined in ANSI C37 and NEMA SG 4. All high voltage parts excluding the roof bushings are completely enclosed within grounded metal barriers. Secondary control compartment and primary circuits are isolated from each other by barriers.

Siemens power circuit breakers carry a type designation as shown in Table 1. This designation may appear on draw- ings and familiarity with them will simplify communications with the factory.

C37.04 AC High-Voltage Circuit Breakers - Basis of Rating C37.06 AC High-Voltage Circuit Breakers - Preferred Ratings C37.09 AC High-Voltage Circuit Breakers - Test Code SG 4 Alternating-Current High-Voltage Circuit Breakers

Table 1. Power Circuit Breaker Designation

DESIGN TYPE

Bolted Cabinet SDV-4A

Receiving, Handling & Storage

Receiving

Each type SDV circuit breaker is securely blocked and braced for shipment. Every precaution is taken to insure its safe arrival. Relatively delicate instruments may be included and the circuit breakers must be handled carefully when unloading and moving.

Inspection

Inspect the equipment as soon as possible after receiving for any damage that may have occurred in transit. Before unloading, make a physical inspection of the circuit breaker, checking for shipment damage or indications of rough handling by the carrier. Check the shipping manifest to be certain that all items have been received. If there is a shortage, make certain it is noted on the freight bill and contact the carrier immediately. Notify the Siemens sales office of any shortage or damage.

Shipping Damage Claims

IMPORTANT: The way visible shipping damage is

treated by consignee prior to signing the delivery receipt can determine the outcome of the damage claim to be filed.

Notification to carrier within the 15 day limit on concealed damage is essential if loss resulting from unsettled claims is to be eliminated or minimized.

1. When shipment arrives, note whether equipment is properly secured for transit. Note trailer number on which the equipment arrived. Note blocking of equipment. During unloading, make sure count agrees with delivery receipt.

2. Make immediate inspection for visible damage upon arrival, and prior to unloading. When total inspection cannot be made on vehicles prior to unloading, close inspection during unloading must be performed and visible damage noted on the delivery receipt. Take pictures if possible.

3. Any visible damage must be noted on the delivery receipt and acknowledged with the driver’s signature. The damage should be detailed as much as possible. It is essential that a notation “Possible internal damage, subject to inspection” be included on delivery receipt. If the driver will not sign the delivery receipt with damage noted, the shipment should not be signed for by the consignee or his agent.

4. Notify the Siemens sales office immediately of any damage.

5. Arrange for a carrier inspection of damage immediately.

IMPORTANT: Do not move equipment from the place it was set when unloading. Equipment must be inspected by carrier prior to handling after receipt. This eliminates loss due to claims by carrier that equipment was damaged or further damaged on site after unloading.

6. Be sure equipment is properly protected from any further damage by covering it properly after unloading.

7. If practical, make further inspection for possible concealed damage while the carrier’s inspector is on site. If inspection for concealed damage is not practical at the time the carrier’s inspector is present, it must be done within 15 days of receipt of equipment. If concealed damage is found, the carrier must again be notified and inspection made prior to taking any corrective action to repair. Also notify Siemens sales office immediately.

8. Obtain the original of the carrier inspection report and forward it along with a copy of the noted delivery receipt to the Siemens sales office. Approval must be obtained by Siemens from the carrier before any repair work can be performed. Before approval can be obtained, Siemens must have the documents. The carrier inspection report and/or driver’s signature on the delivery receipt does not constitute approval to repair.

Note: Any adverse judgment as to whether the equipment was properly loaded or properly prepared by shipper for over-the-road travel cannot be made at the destination. Shipments are not released from the factory without a clear bill of lading. Approved methods are employed for preparation, loading, blocking and securing of the equipment before it leaves the Siemens factory. Therefore, if the equipment is received in a damaged condition, this damage to the equipment had to occur while enroute due to conditions beyond Siemens control. If the procedure outlined above is not followed by the consignee, purchaser, or his agent, Siemens cannot be held liable for repairs. Siemens will not be held liable for repairs in any case where the work was performed prior to authorization from Siemens.

Receiving, Handling & Storage

Heavy weight with a high center of gravity. Can cause death, serious injury or property

damage.

Observe all handling instructions in this instruction manual to prevent tipping or dropping of equipment.

Lifting and Moving

There are a number of methods that can be used in handling the breaker, which when properly employed, will not damage the breaker. The handling method used will be determined by conditions and available equipment at the installation site. Refer to the breaker nameplate for the weight. Lifting with a crane by the use of sling and lifting lugs is the preferred method of handling; however, overhead obstructions often dictate the method to be used. Fork lift trucks may be used prior to removal of wooden skids. Be sure that the forklift blades pass completely under the breaker.

60.0"

Refer to Figure 2 for lifting of the breaker using a sling.

Each power circuit breaker has provisions for attaching lifting cables. Lifting lugs are provided on each side of the breaker, which are designed for use with a sling or hooks of the proper size and a crane of adequate height and capacity. Refer to the breaker nameplate for the weight.

Lifting Power Circuit Breaker with Crane

Recommended lifting of power circuit breakers is by means of cables connected to an overhead crane. The cables are connected to the lifting lugs on the top of the breaker as illustrated in Figure 2. A crane with sufficient height should be used so the load angle (from horizontal) on the lifting cable will be at least 63 degrees, when viewed from the front or the rear. The minimum recommended cable length to achieve proper load angle is 134 inches hook end to hook end. A lesser angle (shorter cable) could cause damage to the equipment.

Figure 2. Lifting Power Circuit Breaker - with Crane.

Storage

When it is necessary to store a power circuit breaker in an area exposed to the weather or under humid conditions, energize the space heaters provided and make certain that any vents are uncovered to allow air to circulate. If at all possible, install the breaker at the permanent location even though it may be some time before the equipment is used. It is also recommended that the breaker receive periodic inspection during storage.

Access to the heater circuit is gained by opening the door to the instrument panel compartment. Refer to wiring diagram drawing for space heater circuit connections. Lubricate hinges and other moving parts.

Installation

Location

The breaker should be located so that it is readily accessible for manual operation and inspection. Ample clearance should be provided for doors and panels to swing open, or to be removed for servicing the breaker.

Preparation for Installation

Prior to installation of a power circuit breaker, study this instruction book and the breaker drawings, such as outline, CT diagram, elementary diagram, connection diagram, relay panel diagram and electrical bill of material, and nameplate engraving. Special attention should be given to the foundation information contained in this manual as well as the information provided on the equipment drawings. Be sure that the foundation conforms to the requirements described in this manual and the outline drawing. SDV breakers are shipped with the legs positioned for shipment. The legs must be removed, turned to the proper position and set to the desired height. Directions are given in the notice decal.

“X” Bracing Installation Instructions (for High Seismic Applications Only)

Once the SDV breaker is set in place at the correct height with the legs correctly installed, “X” bracing must be added to each of the four sides. Figure 3 shows appropriate installation for the breaker at its highest elevation. Other breaker heights will use a similar configuration. The bracing is to run from the first hole below (nearest) the cabinet on one leg to the bottom hole of the opposite leg. When both braces are installed on any side of the breaker, they form the letter “X”.

The bracing is to be attached to each leg using 1 set of 0.5 inch SAE Grade No. 5 hardware (torqued to 50-75 ft-lbs.). The “X” bracing bars have a series of overlapping holes to allow appropriate length adjustment. The two bars forming each brace will use 2 sets of 0.5 inch SAE Grade No. 5 hardware (torqued to 50-75 ft-lbs.) installed in the overlapping holes. Refer to Figure 3 for hardware requirements.

Figure 3. “X” Bracing Installation (High Seismic Applications Only).

Installation

Foundation-General Requirements

Prior to installation of the breaker, careful design, planning and construction of the foundation or base on which the breaker will rest must be made. A thorough analysis and careful construction may alleviate many problems at the

time of installation, and during operation. It is important that a relatively level surface be provided capable of supporting the weight of the breaker, and 0.75 inch diameter anchor bolts are recommended. Figures 4 illustrates typical locations for anchor bolts. No special leveling procedures are required.

Figure 4. Anchoring SDV-4A Power Circuit Breaker.

Electrical Connections

Hazardous voltages. Will cause death, serious injury, and

property damage.

De-energize and properly ground high voltage conductors before working on or near them. The user must adjust the breaker height to ensure compliance with safety codes for electrical clearance.

Primary Lead Connections

The primary leads should be brought down from above the breaker if possible, with adequate clearance to other parts, and with the proper supports so that the breaker bushings are not subjected to excessive strains.

The leads should be sized to have a capacity at least equal to the maximum operating current of the circuit and within the rating of the breaker. Connections are to be made to the bolted terminals of the bushings and must be securely tightened to a clean, bright surface to assure good contact.

Ground Connections

Diagonally opposite grounding pads are provided for connecting the cabinet to ground, using at least a 4/0 AWG conductor on each pad. A good low-resistance ground is essential for adequate protection and for proper functioning of electronic components such as protective relays.

Provision for connecting to ground pads must be made in such a manner that a reliable ground connection is obtained. Consult latest National Electrical Code or National Electric Safety Code for ground connection standards.

Secondary Control Wiring

All secondary control wiring installed by the factory is neatly routed and secured in place. Make all field connections in a similar manner. Check that the relay panel (if so equipped) clears any additional wiring installed.

A conduit panel opening is provided in the bottom of the relay and control compartment for the connection of control circuits. The control wires should be run separately from high voltage wiring to prevent inductive coupling between them and should be sized for full operating current to avoid a drop in voltage below that specified on the nameplate. All conduits should be sealed off at their entrance to the relay and control compartment.

Terminal blocks are provided inside the relay and control compartment for the connections necessary for the control wiring, bushing current transformers and relay panel (if so equipped). These terminal blocks are located inside the control compartment immediately behind the control compartment access door.

Connection diagrams are provided with each breaker and will be found in the pocket inside the control compartment door.

Instrument Transformers

Current Transformers Figure 5 illustrates bushing (toroidal) current transformers

installed in the primary compartment of a circuit breaker. The circuit breaker roof bushings pass through the transformers. Type BCM current transformers are of the toroidal type mounted in the circuit breaker primary compartment. Up to two current transformers may be mounted around each roof bushing. The bushing current transformer connections are wired to separate terminal blocks located in the control and relay compartment.

Hazardous voltage. Will cause death, serious injury, and

property damage.

Current Transformers must not be operated with an open circuit and must be either connected to a burden or short circuited and grounded at the terminal blocks.

2088-98

Figure 5. Type BCM CT’s Installed in primary compartment.

View shown is looking up into cabinet roof from below

Installation Checks and Initial Functional Tests

Introduction

This section provides a description of the inspections, checks and tests to perform on the circuit breaker prior to operation.

Inspections, Checks, And Tests Without Control Power

Vacuum breakers are normally shipped with the primary contacts open and the springs discharged. However, prior to starting the inspection process, it is critical to

first

verify that the control power is de-energized and the springloaded mechanisms are in the discharged condition.

De-energizing Control Power in a Power Circuit Breaker To de-energize the control power, open the disconnect device in the secondary control compartment. Figure 6 shows the location of this disconnect in a standard breaker.

The control power disconnect device is located on the control panel in the secondary control compartment. Figure 6 shows a knife switch with fuses. Opening the knife switch de-energizes control power to the circuit breaker. In some breakers pullout type fuse holders or molded case breakers are used in lieu of knife switches. Removal of the fuse holder or opening the molded case breaker accomplishes the same result: control power is disconnected.

Spring Discharge Check (Figure 7)

Hazardous voltages and high-speed mechanical parts.

Will cause death, serious injury or property damage.

Read instruction manuals, observe safety instructions and use qualified personnel.

The spring discharge check consists of simply performing the following tasks in the order given. This check assures that both the tripping and closing springs are fully discharged.

1. De-energize control power.

2. Press Trip pushbutton.

3. Press Close pushbutton.

4. Again press Trip pushbutton.

5. Verify Spring Condition Indicator shows DISCHARGED.

2078-98

6. Verify Main Contact Status Indicator shows OPEN.

Manual Trip

Manual Close

2082-98

Figure 7. Operator Control Panel of Power Circuit Breaker.

Figure 6.

2089-98

Control Power Disconnects in Power Circuit Breaker.

Installation Checks and Initial Functional Tests

Physical Inspections

1. Verify that the rating of the circuit breaker is compatible with the system.

2. Perform a visual shipping damage check. Clean the breaker of all shipping dust, dirt and foreign material.

Manual Spring Charging Check

1. Insert the manual spring charging lever into the manual charge handle socket as shown in Figure 8. Operate the lever up and down until the spring condition indicator shows the closing springs are Charged, and remove the lever from the socket.

2. Repeat the Spring Discharge Check.

3. Verify that the springs are discharged and the breaker primary contacts are open by observing the indicator positions.

connected to the circuit breaker. (Refer to the specific wiring information and rating label for your circuit breaker to determine the voltage required and where the control voltage signal should be applied.) When control power is connected to the breaker, the closing springs should automatically charge if the control power disconnect (see Figure 6) is closed.

The automatic spring charging features of the circuit breaker must be checked. Control power is required for automatic spring charging to take place.

1. Use the manual Close and Trip controls (Figure 7) to first

Close and then Open the circuit breaker contacts. Verify contact positions visually by observing the Open/Closed indicator on the circuit breaker.

2. Open control power circuit by opening knife switch

shown in Figure 6.

3. Perform the Spring Discharge Check again. Verify that the closing springs are discharged and the primary contacts of the circuit breaker are open.

Final Mechanical Inspection and Testing Without Control Power

Before the circuit breaker is energized, it must be thoroughly inspected and tested. Correct any deviations before energization.

2090-98

Figure 8. Manual Charging of Closing Springs.

As-Found and Vacuum Check Tests - Perform and record

the results of both the As-Found insulation test and the vacuum check high-potential test. Procedures for these tests are described in the Maintenance Section of this manual.

Automatic Spring Charging Check Note: A temporary source of control power and test leads

may be required if the control power source has not been

Inspection

Check the following points:

1. Make a final mechanical inspection of the circuit breaker.

Verify that the contacts are in the Open position, and the closing springs are Discharged.

2. Make sure the breaker is properly set up and reason-

ably level on its foundation and appropriately anchored to the foundation.

3. Check the tightness of all hardware on the cabinet, ad-

justable legs, bushings, bus bars and operator mechanism.

4. See that the operating mechanism has been properly

lubricated.

5. Blocking, supports and other temporary ties removed

from breakers, instruments, relays, etc.

6. Proper fuses correctly placed.

7. Temporary wiring jumpers (used on the secondaries of

current transformers wired to external devices, as shown on wiring diagrams) removed.

8. Ground connections properly made.

Installation Checks and Initial Functional Tests

9. Incoming primary and secondary connections properly made and checked for shorts or undesired grounds.

10. See that all covers, and bolted connectors are securely fastened.

11. Relays coordinated with other relays and protection devices on the system. Refer to relay instructions before making any adjustments.

12. Examine the vacuum interrupters for damage, and wipe the interrupters and other insulating parts with a clean, dry cloth.

13. All filters in vent areas are clean and free of shipping or construction material.

14. Retouch any paint that has been damaged during installation.

Shipping bracing and tag between phase barriers (on units so equipped) may damage circuit breaker.

May result in damage to equipment.

Remove bracing and tag (on units so equipped) before energizing breaker high voltage.

Testing

High Potential tests employ hazardous voltages.

Will cause death or serious injury.

Follow safe procedures, exclude unnecessary personnel and use safety barriers. Keep away from the breaker during application of test voltages. After test completion, ground both ends and the middle ring (if visible) of the vacuum interrupter to dissipate any static charges.

Note: No hazardous X-radiation is produced with closed contacts, or with open contacts with rated operating voltage applied.

Excessive test voltages. May result in damage to equipment.

Do not perform dielectric tests at test voltages exceeding the ratings of the tested equipment.

1. An insulation resistance test is advisable on the control circuit to be sure that all connections made in the field are properly insulated.

2. A dielectric test, if possible, should be made on the high voltage circuit for one minute at the following voltages corresponding to the rated voltage of the equipment. The voltage should be raised gradually and the circuit under test should sustain the voltage for one minute. When the test is performed with the breaker open, the integrity of the vacuum interrupter will also be verified. If these levels cannot be sustained and there is no other source for the failure, the interrupter must be replaced.

Rated

Maximum

Voltage

kV (rms)

15.5

25.8, 27.6

Power Frequency Withstand

kV (rms)

50 60

Field Test Voltage

kV (rms) kV (dc)

37.5 45

63.6

Note: The DC test voltage is given as a reference only. It represents values believed to be appropriate and approximately equivalent to the corresponding power frequency withstand test values specified for each voltage rating. The presence of this column in no way implies any requirement for a DC withstand test on AC equipment or that a DC withstand test represents an acceptable alternative to AC withstand tests. When making DC tests, the voltage should be raised to the test value in discreet steps and held for a period of one minute.

Vacuum interrupters may emit X-radiation. Can cause serious injury.

X-rays can be produced when a high voltage is placed across two circuit elements in a vacuum.

Keep personnel more that six (6) feet away from a circuit breaker under test. All normal metallic doors and panels must be installed during tests.

Field Dielectric Tests are recommended when new units are installed, or after major field modifications. The equipment should be put in good condition prior to the field test. It is not expected that equipment shall be subjected to these tests after it has been stored for long periods of time or has accumulated a large amount of dust, moisture, or other contaminants without being first restored to good condition.

Interrupter/Operator Description

Introduction

Type SDV circuit breakers include three vacuum interrupters, a stored energy operating mechanism and necessary electrical controls. On some circuit breaker ratings, insulating barriers are located between the vacuum interrupters.

This section describes the operation of each major subassembly as an aid in the operation, installation, maintenance and repair of the type SDV vacuum circuit breaker.

Vacuum Interrupters

The operating principle of the vacuum interrupter is simple. Figure 9 is a cutaway view of a typical vacuum interrupter. The entire assembly is sealed after a vacuum is established. The interrupter stationary contact is rigidly attached to the end cap which serves as one terminal of the interrupter. The interrupter movable contact is free to move in a guide, and is connected to the operating mechanism by a system of linkages. The metal bellows assembly provides a secure seal around the movable contact, preventing loss of vacuum while permitting movement of the contact.

Fixed Contact Current Connection

When the two contacts separate, an arc is initiated which continues conducting up to the following current zero. At current zero, the arc extinguishes and any conductive metal vapor which has been created by and supported the arc condenses on the contacts and on the surrounding vapor shield. Contact materials and configuration are optimized to achieve arc motion and to minimize switching disturbances.

The arc drawn in the vacuum breaker is not cooled. The metal vapor plasma is highly conductive and the resulting arc voltage only attains values between 20V and 200V. For this reason and because of the short arcing times, the arc energy developed in the breaker is very small. This also accounts for the long life expectancy of the vacuum interrupter.

Phase barriers are provided on all 25.8kV and 27.6kV class type SDV units as shown in Figure 10. These plates of insulating material are attached to the circuit breaker housing and provide suitable electrical insulation between the vacuum interrupter primary circuits. Phase barriers are not required in 15.5kV class type SDV units, but are available as an option.

Ceramic Insulator

Arc Shield

Fixed Contact

Moving

Contact

Ceramic

Insulator

Metal Bellows

Guide

Moving Contact Current

Connection

Figure 9. Cutaway View of SDV Vacuum Interrupter.

2097-98

Figure 10. Breaker with Interphase Barriers.

Stored Energy Operating Mechanism

The stored energy operating mechanism of the SDV circuit breaker is an integrated arrangement of springs, solenoids and mechanical devices designed to provide a number of critical functions. The energy necessary to close and open the contacts of the vacuum interrupters is stored in powerful tripping and closing strings. These springs are normally charged automatically, but there are provisions for manual charging. The operating mechanism that controls charging, closing and tripping functions is fully trip-free, i.e., spring charging does not automatically change the position of the primary contacts, and the closing function may be overridden by the tripping function at any time.

Interrupter/Operator Description

Figure 11. Breaker Open - Closing Springs Discharged. Figure 12. Breaker Open - Closing Springs Charged.

Modes Of Operation - Discussion

Some maintenance procedures are more easily understood when the operating mechanism modes of operation are described in detail. The next few paragraphs explain the five modes or status conditions (charging, closing, trip-free, opening and rapid auto reclosing) of the stored energy operating mechanism.

Note: All discussion of modes of operation assumes that the reader is viewing the operator from the front, or from the left hand side.

Spring Charging Mode - Figures 11 and 12 show several key components of the operator mechanism in positions corresponding to the breaker open, with the closing springs discharged (Figure 11) and charged (Figure 12). Figure 13 shows portions of the operator mechanism that manually or electrically charge the closing springs. The drive cam (20), the closing spring crank arms (Figure 15) and spring condition indicator cam (18) are directly keyed to the main cam shaft (3). The main cam shaft rotates counterclockwise. The closing springs are attached to the crank arms and are extended during the charging cycle.

Figure 13 shows the ratchet wheel (15) which is free to rotate about the main cam shaft (3). The ratchet wheel is driven by either the charging motor or the manual charge handle socket (52). When the springs are charged electrically, the motor eccentric (100) introduces a rocking mo-

tion into the drive plate (13). As this plate rocks back and forth, the upper pawl (24-1) (which is connected to the drive plate) imparts counterclockwise rotation of the ratchet wheel (15), one tooth at a time. The lower pawl (24-2) acts as a holding pawl during electrical charging.

When the springs are charged manually, up and down pumping action of the spring charging handle in the manual charge handle socket (52) causes the pawl plate (11) to rock back and forth through the movement of the manual charging link (48). The lower pawl (24-2) drives the ratchet plate counterclockwise during manual charging, and the upper pawl (24-1) becomes the holding device.

At the beginning of the charging cycle, ratchet pin (16) is at the 12 o’clock position. The ratchet pin is connected to the ratchet wheel. Upon being advanced by ratchet action to the 6 o’clock position, this pin engages the drive arms (8) which are keyed to the main cam shaft. Consequently, counterclockwise rotation of the ratchet wheel causes the ratchet pin to drive the main cam shaft counterclockwise. When the ratchet pin reaches the 12 o’clock position, the closing springs are fully charged. Driving pawl (24-1) is disengaged, the spring condition indicator cam (18) has rotated allowing the spring charged flag (132) to drop into the lower (charged) position, which also operates the motor cutoff switch (LS1) and spring charged switch (LS2) (258) (see Figures 14 and 19). The closing springs are restrained fully charged by close hatchet (22) against close shaft (72).

Interrupter/Operator Description

Drive Plate

Upper Pawl 24-1

Drive Arm 8

Ratchet Wheel 15

Lower Pawl 24-2

Manual Charging Link 48

Pawl Plate 11

Charging Motor Eccentric 100

Ratchet Pin 16

Main Camshaft 3

Close Shaft 72

Manual Charge Handle Socket 52

Figure 13. Pawl and Ratchet Drive.

Closing Mode (Figure 14) - Energizing the close solenoid

(265) pulls the solenoid armature against the closing shaft actuator (75) and causes the close shaft (72) to rotate approximately 15°. If the closing springs are charged, the close hatchet (22) will be released by this rotation allowing the main cam shaft (3) to be driven by the closing springs. Depressing the manual close button on the operator panel causes the rotation of the close shaft (72) by the upper end of the close shaft actuator (75). Rotation of the main cam shaft (3) in a manual closing operation is identical to that of the electrical closing operation. As the main cam shaft (3) rotates, the cam follower (115) is driven by drive cam (20) and the main link (120) is forced outwards, and rotation of the jack shaft assembly (217) occurs. There are three drive links attached to Point “A” of each of the three jack shaft drive plates. Each drive link is connected to the movable contact of one vacuum interrupter. Closing rotation (counterclockwise) of the jack shaft assembly closes the contacts of the three vacuum interrupters. During the closing operation, rotation of jack shaft assembly (217) forces the opening (i.e., tripping) spring into its charged position.

Trip Free Mode - If at any time during breaker closing, the trip shaft (79) (Figure 11) operates as a result of either an electrical or mechanical trip, the trip hatchet (99) is free to rotate. When the trip hatchet (99) rotates, cam follower (115) is displaced by the drive cam (20) without motion of the jack shaft (217).

Figure 14. Closing Mode.

Opening Mode - Opening or tripping the vacuum interrupter

contacts is accomplished by rotation of the trip shaft (79). Rotation may be produced either electrically, by energizing the trip solenoid (266) (Figure 12), or manually by pressing the trip button. Energizing the trip solenoid causes the lower arm of the trip actuator (152) to rotate counterclockwise. Pressing the trip button causes the trip actuator upper arm to move, again producing rotation of the trip shaft. All of the linkages are trip free, and tripping or opening is unaffected by charging status of the closing springs or position of the drive cam (20).

Rapid Auto-Reclosing Mode - The closing springs are automatically recharged by the motor driven operating mechanism immediately following a closing operation. The operating mechanism is capable of the open-close-open duty cycle required for rapid auto reclosing. A trip latch check switch prevents release of the closing spring energy if the trip hatchet (99) is not in its reset position. This ensures the mechanism does not operate trip free on an instantaneous reclosure. The user must supply external time delay to assure minimum reclose time interval of 0.3 seconds to comply with ANSI C37.06-2000.

Closing And Tripping Springs - The stored energy assembly includes dual closing springs and a single opening spring. Figure 15 shows the three springs and their linkages to the charging devices. The two closing springs are

Interrupter/Operator Description

connected to crank arms mounted on the rotating main cam shaft. The closing springs are extended, and charged, by rotation of the crank arms connected to the movable ends of the springs. The fixed ends of these springs are attached to a support arm, which in turn is bolted to the structure of the circuit breaker operator.

The opening spring is connected to the jack shaft. When the circuit breaker closes, rotation of the jack shaft causes the opening spring push rod to compress and charge the opening spring. Consequently, the opening spring is automatically charged whenever breaker contacts are closed.

Trip Free Operation - The type SDV circuit breaker is mechanically and electrically trip free. This important function enables the breaker to be tripped before, after or during a closing operation. Whenever the circuit breaker trip shaft is moved as the result of manual or electrical signals, a) a closed breaker will open, b) a breaker in the process of closing will not complete the close operation and will remain open, or c) an open breaker will not be able to be closed.

Damper - Type SDV circuit breakers are equipped with a sealed, oil-filled, viscous damper, or shock absorber (Fig- ure 15). The purpose of this damper is to limit overtravel and rebound of the vacuum interrupters’ movable contacts at the end of an opening operation. The damper action affects only the end of an opening operation.

Motor

One configuration is used for 15.5kV 1200A circuit breakers, while a somewhat different damper and linkage system is used for all other ratings of SDV-4A circuit breakers. (see figure 26)

The outer tube and (inner) damper remain uncoupled until the end of the opening operation is reached. At this time, the tube’s striker block contacts the damper piston, to begin control of movable contact dynamics.

Two different damper and linkage systems are used on SDV4A circuit breakers.

Manual Spring Charging - Manual charging of the closing springs is accomplished using a lever in lieu of the spring charging motor. Figure 16 shows the principal components of the manual spring charging mechanism.

The manual spring charging lever is inserted into a rectangular socket in the hand operator. The socket is accessible through the operator control panel of the circuit breaker operator. Moving the lever up and down in a cranking or pumping motion causes rotation of the internal spring charging components.

Note: Manual spring charging components will be damaged by overcharging.

Manual charging action must be suspended when the operator sees the “Charged” status indicator appear on the operator control panel of the circuit breaker and hears the sound of impact against the internal closing latch.

Damper

Jack Shaft

Crank Arms

Closing Springs

Opening Spring

2100-98

Figure 15. Closing and Opening Springs, Spring Charging Motor and Damper.

The cylindrical body of the damper is secured to the breaker operator frame, with a yoke. The damper’s piston and striker tip protrude from the opposite end of this cylinder (the upper end as installed on the breaker). A striker block is fixed within an outer tube, which is guided by the cylindrical body of the damper. The end of the outer tube is attached to the breaker jack shaft.

2090-98

Figure 16. Manual Charging of the Closing Springs.

Interrupter/Operator Description

Spring Charging Motor - Figure 15 shows the spring charging motor mounted at the top of the right side of the circuit breaker operator housing. A mounting bracket holds the motor firmly in place. A universal motor is used to permit operation on either AC or DC control power.

The motor control circuits call for automatic charging of the springs by the motor whenever control power is available and the springs are discharged. The springs automatically recharge following a closing operation.

Electrical connections to the motor utilize a quick disconnect termination for easy inspection or removal.

Close Solenoid, Trip Solenoid and Anti-Pump Relay - Figure 17 shows the two solenoids controlling operation of

the circuit breaker by external electrical signals.

When the close solenoid is energized, it causes the two closing springs to be released from their extended or charged state. This forces the three insulating coupling rods to move the movable vacuum interrupter contacts toward the fixed contacts and close the circuit breaker.

The anti-pump relay (Figure 32) electrically isolates signals to the close solenoid such that only one releasing action by the close solenoid can occur during each application of the close command. The circuit breaker must be tripped, the springs recharged and the closing signal removed (interrupted) before the close solenoid can be energized a second time.

Auxiliary Switch - Figure 18 shows the breaker mounted auxiliary switch. This switch provides auxiliary contacts for control of circuit breaker closing and tripping functions. Contacts are available for use in relaying and external logic circuits. This switch is driven by linkages connected to the jack shaft. The auxiliary switch contains both “b” (Normally Closed) and “a” (Normally Open) contacts. When the circuit breaker is open, the “b” switches are closed and the “a” switches are open.

When the trip solenoid is energized, it allows rotation of the jack shaft by the tripping spring. This rotation pushes the insulating coupling rods attached to the movable contacts of the three vacuum interrupters, and the circuit breaker contacts are opened.

Electrical connections to the close solenoid and trip solenoid are made through quick disconnect terminations.

Trip Solenoid

Close Solenoid

2093-98

Figure 17. Close (Left) and Trip (Right) Solenoids.

2092-98

Figure 18. Auxiliary Switch.

Limit Switches (Figure 19) - The motor cutoff switch (LS1)

is used to sense the position of the drive mechanism. This switch de-energizes the charging motor when the Charged position of the closing springs is reached. When the closing springs are discharged, this switch energizes the control circuit powering the spring charging motor.

Spring charged switch (LS2) operates simultaneously with motor cutoff switch (LS1). The spring charged switch allows the close solenoid to be energized only when the springs are charged, and also is part of the anti-pump circuitry.

The trip latch check switch (LS3) operates when the trip latch linkage is in the reset position.

Standard Schematic Diagrams Note: Figure 20a shows a typical schematic for a circuit

breaker which is specifically intended for reclosing application (standard for SDV breakers). Figure 20b shows a breaker with capacitor tripping. These are typical - refer to the specific drawing for your project.

Interrupter/Operator Description

LS3

2100-98

Figure 19. Circuit Breaker Limit Switches.

Inspection of the schematic diagrams shown in Figures 20a- 20b provides a clear picture of the logic states of the various devices for the three basic control functions.

These are: 1) automatic charging of the closing springs;

2) electrical closing of the primary contacts and 3) electrical tripping of the primary contacts.

Automatic spring charging by charging motor occurs when secondary control power is available, and motor cutoff switch LS1 has not operated. The springs are automatically recharged after each closing operation.

Electrical closing occurs with closing control power applied and when

all

of the following conditions exist:

1. External close switch 01/C is closed.

2. Anti-pump relay 52Y is not energized.

3. Auxiliary switch 52b indicates the breaker is in the open position.

4. Limit switch LS3 shows that the trip latch has been reset.

5. Limit switch LS2 indicates that the closing springs are charged.

Electrical tripping occurs with tripping control power applied and when the auxiliary switch 52a shows the breaker is closed, and a trip signal is provided by the control switch 01/T or the protective relays. While external control power is required for either electrical closing or tripping, the circuit breaker can be manually charged, closed and tripped without external control power.

Capacitor Trip Device (Optional)

The capacitor trip device is an auxiliary tripping option providing a short term means of storing adequate electrical energy to ensure breaker tripping.

LS1/ LS2

Hazardous stored voltage. Will cause death, serious injury or property

damage.

Make certain the energy stored in the capacitor is discharged by grounding the capacitor terminals before touching any of the wiring.

2101-98

2102-98

This device is applied in breaker installations lacking independent auxiliary control power or station battery. In such installations, control power is usually derived from the primary AC source. In the event of a primary source fault, or disturbance with accompanying depression of the primary source voltage, the capacitor trip device will provide short term tripping energy for breaker opening due to relay operation.

Refer to Figure 20b. An electrolytic capacitor resides across the tripping supply voltage connected through a half wave rectifier and resistor. The rectifier allows the capacitor to assume a charge approximating the peak voltage of the AC tripping supply voltage. The series resistor limits the magnitude of charge current flowing into the capacitor.

The charged capacitor is then connected across the breaker trip coil circuit through an external contact which closes upon trip command.

The capacitor size and charge current magnitude are tuned to the inductance and resistance of the tripping solenoid, an RLC series circuit, to produce a discharge current through the solenoid which emulates the magnitude of current and current duration which the solenoid would experience if operated from a DC tripping supply voltage.

Interrupter/Operator Description

LEGEND

LS1 Motor Cutoff LS2 Spring Charged LS3 Trip Latch Check

52a Aux Switch, Open When Bkr OPEN 52b Aux Switch, Closed When Bkr OPEN 52 SRC

Closing, Spring Release Coil 52T Trip 52Y Anti Pump

08 Motor Power Disconnect 08T Close & Trip Power Disconnect 69 Closing Cutout Switch 88 Motor TPX Terminal Block 01/C Control Switch Close (Remote) 01/T Control Switch Trip (Remote) G Green Light (Remote) R Red Light (Remote) W White Indicating Light (Remote)

TPX

(+)

Power

Supply

(-)

52 a & b Spare Contacts

15 12

52 a

TPXa16

15 16

TPX5215

51 53

TPX

52 b

TPX5417

08T

15A

10A

TPX

21 22

55 57 20

TPX

52 a

TPX

52 b

21 58

TPX

TPX11

59 24

52 a

23 60

TPX

61 26

52 b

25 62

Notes on Schematic Arrangement Schematics are shown with:

1. Closing Springs Discharged

2. Breaker Open Note that, in this condition, the trip

latch is free to reset, but is temporarily blocked until the closing springs are partially recharged. Prior to full spring charge, LS3 (NO) closes, and LS3 (NC) opens.

Prot Relays

3TPX

TPX 4

52b

52Y

SRC

LS3

LS2

TPX 5

4 21

32 31

NO C

NC C

TPX

52 a

52Y

LS2

TPX

52 b

TPX58

52 a

ACDC

Power

Supply

TPX231

LS1

10A

08T

15A

TPX

C C

2 4

LS1

Figure 20a. AC and DC Control Power (Reclosing).

Interrupter/Operator Description

LEGEND

LS1 Motor Cutoff Switch LS2 Spring Charged Switch LS3 Trip Latch Check Switch 52a Aux Switch, Open When Bkr Open 52b Aux Switch, Closed When Bkr Open 52 SRC Closing, Spring Release Coil 52T Trip Coil 52Y Anti Pump Relay

08 Motor Power Disconnect

Close & Trip Power Disconnect

08T

Closing Cutout Switch

69 88 Motor TPX Terminal Block CTD

Capacitor Trip Device Control Switch Close (Remote)

01/C

Control Switch Trip (Remote)

01/T G Green Light (Remote) R Red Light (Remote) W White Indicating Light (Remote)

TPX

Power

Supply

51 16

52 a

15TPX 52

52 a & b Spare Contacts

53 18

TPX TPX TPX20

17 18

52 b

TPXTPX 17

08T

15A

10A

6 4

10A

52 a

56 58

57 22

52 b

2119 TPX

59 24

TPX TPX 26

52 a

TPXTPX 23

TPX 3

23 1TPX

NO C C

LS1

TPX 2

08T

15A

Notes on Schematic Arrangement

52 b

25 62

Schematics are shown with:

1. Closing Springs Discharged

2. Breaker Open Note that, in this condition, the trip

latch is free to reset, but is temporarily blocked until the closing springs are partially recharged. Prior to full spring charge, LS3 (NO) closes, and LS3 (NC) opens.

41 25

CTD

OFF

N E O N

L T

OFFON115

230

10A

+ C

A P

PROT RELAYS

TPX

52 a

8TPX

10B

TPX

52b

52Y

LS3

LS2

TPX

SRC

4 21

CNCC

52Y

13C

LS2

TPX

52 b

TPX

TPXa11

Figure 20b. AC Control Power (with Capacitor Trip).

Maintenance

Inspection and Maintenance Intervals

Periodic inspections and maintenance are essential to obtain safe and reliable operation of the SDV circuit breaker.

When SDV circuit breakers (manufactured beginning January, 1992) are operated under “Usual Service Conditions”, maintenance and lubrication is recommended at five year (one year if manufactured before January, 1992) intervals or at the number of operations indicated in Table 3. “Usual” and “Unusual” service conditions for AC High-Voltage Circuit Breakers are defined in ANSI C37.04, Section 4 and ANSI C37.010, Section 4. Generally, “usual service conditions” are defined as an environment in which the equipment is not exposed to excessive dust, acid fumes, damaging chemicals, salt air, rapid or frequent changes in temperature, vibration, high humidity, and extremes of temperature.

The definition of “usual service conditions” is subject to a variety of interpretations. Because of this, you are best served by adjusting maintenance and lubrication intervals based on your experience with the equipment in the actual service environment.

Regardless of the length of the maintenance and lubrication interval, Siemens recommends that circuit breakers should be inspected and exercised annually.

of inspection, periodic cleaning, and preventive maintenance schedule will depend upon the operation conditions. NFPA Publication 70B, “Electrical Equipment Maintenance” may be used as a guide to establish such a program. A

preventive maintenance program is not intended to cover reconditioning or major repair, but should be designed to reveal, if possible, the need for such actions in time to prevent malfunctions during operation.

Recommended Hand Tools

Type SDV circuit breakers use both standard American and metric fasteners. Metric fasteners are used for the vacuum interrupters. American fasteners are used in all other locations. This list of hand tools describes those normally used in disassembly and re-assembly procedures.

Open End or Box End Wrenches:

• 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, and 7/8 in.

Socket Wrenches: (1/2” drive preferred)

• 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, and 7/8 in.

• 18, 19 and 24mm (deep sockets)

• Ratchet

• 2 Extensions (6” maximum)

• Torque Wrench (0-150 ft-lbs.)

Hex Keys Wrenches: (socket type preferred)

• 3/16, 1/4 and 5/16 in.

• 8 and 10mm

Hazardous voltages and high-speed mechanical parts.

Will cause death, serious injury or property damage.

Read instruction manuals, observe safety instructions and limit use to qualified personnel.

For the safety of maintenance personnel as well as others who might be exposed to hazards associated with maintenance activities, the safety related work practices of NFPA 70E, parts ll and lll, should always be followed when working on electrical equipment. Maintenance personnel should be trained in the safety practices, procedures and requirements that pertain to their respective job assignments. This manual should be reviewed and retained in a location readily accessible for reference during maintenance of this equipment.

The user must establish a periodic maintenance program to ensure trouble-free and safe operation. The frequency

Miscellaneous:

• Screw Drivers: 0.032 x 1/4 in. wide and 0.055 x 7/16 in. wide

• Pliers

• Light Hammer

• Drift Pins: 1/8, 3/16 and 1/4 in. dia.

Recommended Maintenance and Lubrication

Periodic Maintenance and Lubrication should include all the tasks shown in Table 2. Recommended procedures for each of the listed tasks are provided in this section of the manual.

Failure to maintain the equipment could result in death, serious injury or product failure, and can prevent successful functioning of connected apparatus.

The instructions contained herein should be carefully reviewed, understood, and followed.

The maintenance tasks in Table 2 must be performed regularly.

Maintenance

Table 2: Maintenance Tasks

• Checks of the Primary Power Path

• Checks of the Interrupter Operator Mechanism

• Electrical Control Checks

• High Potential Test

• Inspection and Cleaning of Breaker Insulation

• Functional Tests

For a “quick reference” to these tasks, see “Periodic Maintenance and Lubrication Tasks” chart on page 39.

The list of tasks in Table 2 does not represent an exhaus- tive survey of maintenance steps necessary to ensure safe operation of the equipment. Particular applications may require further procedures. Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to the local Siemens sales office.

The use of unauthorized parts in the repair of the equipment, or tampering by unqualified personnel will result in dangerous conditions which can cause death, serious injury or equipment damage.

Follow all safety instructions contained herein.

De-energize the Circuit Breaker

Prior to performing any inspection or maintenance checks, the circuit breaker must be de-energized and grounded. Principal steps are outlined below for information and guidance.

Be sure that the circuit breaker and its mechanism are disconnected from all electric power, both high voltage and control voltage, before it is inspected or repaired.

After the circuit breaker has been disconnected (isolated) from power lines, attach the grounding leads properly before touching any of the circuit breaker parts.

De-energize the control power to the circuit breaker. Review Figure 6. If the circuit breaker includes the optional capacitor trip unit, the capacitor must be discharged by grounding its terminals.

Perform the Spring Discharge Check, by first pushing the Trip pushbutton, then the Close pushbutton, and finally the Trip pushbutton again. Verify that the circuit breaker is OPEN and the closing spring indicator shows DISCHARGED. See Figure 21, which shows the breaker condition preced- ing the second operation of the Trip pushbutton.

2094-98

Figure 21. Manual Tripping of Circuit Breaker.

Checks Of Primary Power Path

The primary power path consists of the three vacuum interrupters, six bus connections to the bushings, and the roof mounted bushings. These components are checked for cleanliness and condition. The vacuum interrupters are also checked for vacuum integrity.

Some test engineers prefer to perform the contact erosion check during the manual spring charging check of the operator, since charging of the springs is necessary to place the contacts in the closed position.

Also, the vacuum integrity check is usually performed in conjunction with the High Potential tests.

These instructions follow the recommendation that these tests (contact erosion/manual spring charging check, and vacuum integrity/high potential tests) will be combined as described.

Cleanliness Check - Figure 22 is a side view of the type SDV circuit breaker with one of the insulating phase barriers (when so equipped) removed to show the vacuum interrupter, bus connections and roof bushings.

All of these components must be cleaned and free of dirt or any foreign objects. Use a dry lint-free cloth. For stubborn dirt, use a clean cloth saturated with denatured alcohol.

Also inspect the buswork for any evidence of loose bolts, bushings for any evidence of damage, and flexible connectors for tightness and absence of mechanical damage, burning, or pitting.

Maintenance

to the jack shaft by a pull rod. The dashpot is connected to the jack shaft operating shaft by a pushrod linkage.

Figure 22. Side View SDV, Typical.

Checks of the Stored Energy Operator Mechanism

The stored energy operator checks are divided into mechanical and electrical checks for simplicity and better organization. The first series of checks determine if the basic mechanism is clean, lubricated and operates smoothly without control power. The contact erosion check of the vacuum interrupter is also performed during these tasks.

Maintenance and Lubrication Table 3: Maintenance and Lubrication Intervals

ANSI C37.06 Table 7 - Usual Service Conditions Maintenance Based Upon Number of Breaker Closing Operations

Number of

Breaker Type

SDV

Five year interval for SDV breakers manufactured January, 1992 or later.

One year interval for units manufactured earlier.

Years/Closing Operations

5 years1/500 operations

The interrupter operator mechanism is shown in Figure 23 with the access door open and the operator control panel removed to show construction details. Both the tripping spring and the two closing springs are shown. The movable end of each closing spring is connected to a crank arm. The movable end of the opening spring is connected

2100-98

Figure 23. Front View of Operator Mechanism.

Clean the entire stored energy operator mechanism with a dry lint-free cloth.

Check all components for evidence of excessive wear. Place special attention upon the closing spring cranks and the various pushrods and linkages.

Lubricate all non-electrical moving or sliding surfaces with a light coat of synthetic grease or oil. Lubricants composed of diester oils and lithium thickeners will be compatible.

Shell (drawn cup) needle bearings: Use either Beacon (Exxon) 325 (reference 18-658-676-422 and part number 15337-131-001), or Supermil (Amoco) A-72832 (reference 18658-676-423), or Anderol 732 aerosol synthetic fluid grease (reference part number 15-172-816-058).

Pivots, sliding, and/or rolling surfaces and general lubrication: Use Anderol 732 aerosol synthetic fluid grease (reference part number 15-172-816-058).

Fastener Check - Inspect all fasteners for tightness. Locknuts, retaining rings and X-washers are used. Replace any fasteners that appear to have been frequently removed and replaced. X-washers can not be reused and must be replaced any time they are removed

Manual Spring Charging And Contact Erosion Checks -

Perform the Manual Spring Charging Check contained in the section describing the Installation Check and Initial Function Tests. The key steps of this procedure are repeated here.

Maintenance

1. Insert the hand charging lever into the manual charge handle socket at the front of the operator control panel. Figure 16 shows the lever inserted. Up and down motion of the lever charges the closing springs. Continue cranking until the Charged flag appears in the window of the spring indicator.

Tripping spring is charged. If trip latch is moved, high-speed movement

of components can cause serious injury.

Observe precautions concerning physical contact with components of the circuit breaker subjected to sudden, high speed movement.

2. Press the Close pushbutton. The contact position indicator on the operator control panel should indicate that the breaker contacts are CLOSED.

3. Perform the contact erosion check. Contact erosion occurs when high fault currents are interrupted or when the vacuum interrupter is nearing the limit of its contact life. Determination of acceptable contact condition is checked by measuring the gap between the end of the coupling rod and the bottom of the pivot block, shown in Figure 24. Subtract this measurement from the base dimension recorded on the decal next to the interrupter If the difference is 0.22 inch or more, the interrupter must be replaced.

4. Press the Trip pushbutton

after

completing the contact erosion check. Visually verify the Discharged condition of the closing springs and that the circuit breaker contacts are OPEN.

5. Press the Close pushbutton. Nothing should happen. The manual spring check should demonstrate smooth operation of the operating mechanism.

Vacuum Interrupter Stroke Check (Figure 25)

Careful use of the setup procedure given in Vacuum Interrupter Replacement Section (under Overhaul) will result in accurate setting of the stroke and synchronization of the three phases. The procedure outlined below is useful as a check following adjustment, replacement or other service of the operating linkages but is not intended as a substitute for the setup procedure in Vacuum Interrupter Replacement Section. The accuracy of stroke measurement is highly dependent on the care and consistency used in making the two marks required.

Hazardous voltages and high-speed mechanical parts.

Will cause death, serious injury or property damage.

Read instruction manuals, observe safety instructions and use qualified personnel.

Figure 24. Contact Erosion Check.

2095-98

Groove Tape

2134-99 2135-99

Figure 25a. Vacuum Interrupter Stroke Check.

1. Place the breaker in the OPEN position.

2. Apply a piece of .25” wide or narrower tape (correction tape works well) to the stem of the vacuum interrupter, as shown in Figure 25a, such that when the stem moves the tape will enter the grove in the interrupter stem guide bushing.

3. With breaker still in open position, mark a line on the tape where it intersects the guide bushing. Close the breaker and repeat the marking procedure (Figure 25b).

Maintenance

Damper Assembly Check - SDV circuit breakers contain a viscous damper assembly, shown in Figure 26, and described in some detail on page 16, and in Figure 15.

While performing the manual spring charging check, a simple check of the damper mounting yoke, pin, retaining rings, and the nut for tightness should be completed.

The cylindrical surface of the damper and telescoping tube should be well greased. The full inside periphery of the tube and cylinder should be coated with Beacon 325 or Anderol 732.

2137-99

2136-99

Figure 25b. Vacuum Interrupter Stroke Check.

4. Open the breaker. The stroke is the distance between the two lines. Remove the tape and measure the distance between the two lines and record.

5. Repeat for all phases if desired.

6. The stroke measured with the above procedure will be approximate due to variations in accuracy of line markings. The greater the care taken in marking the lines the more accurate the stroke values will be. In general the measured stroke value should be within 15% of the value given in Appendix Table A-6.

7. The stroke is pre-set for a new breaker at the factory, but the stroke values should be measured and recorded for any new breaker as well as any replacement vacuum interrupter. These values can be used as a benchmark for future evaluations of contact erosion.

Electrical Control Checks

The electrical controls of the type SDV circuit breaker should be checked during inspections to verify absence of any mechanical damage, and proper operation of the automatic spring charging and Close and Trip circuits.

Unless otherwise noted, all of these tests are performed

without

any control power applied to the circuit breaker.

Check Of The Wiring And Terminals

1. Physically check all of the breaker wiring for evidence of abrasion, cuts, burning or mechanical damage.

2. Check all terminals to be certain they are solidly attached to their respective device. Be sure to check the lockingtype quick disconnects used at the close and trip solenoids and charging motor to be certain that they are fully seated and locked on.

Hazardous voltages and high-speed moving parts.

Will cause death, serious injury, or property damage.

Read instruction manuals, observe safety instructions and limit use to qualified personnel.

Enidine Type Ace Type

Figure 26. Damper Assembly.

Automatic Spring Charging Check — Control Power Required - Repeat the automatic spring charging check de-

scribed in the section entitled Installation Checks and Initial Functional Tests.

Primary tasks of this check are:

1. The breaker is energized with control power for this check.

2. When control power is connected to the circuit breaker, the closing springs should automatically charge. Visually verify that the closing springs are charged.

Maintenance

Note: A temporary source of control power and test leads may be required if the control power source has not been connected to the circuit breaker. When control power is connected to the circuit breaker, the closing springs should automatically charge.

Electrical Close And Trip Check — Control Power Required -

For breakers equipped with electrical close and trip switches (either Close/Trip switch, or two pushbuttons):

1. Once the breaker springs are charged, move the breaker Close/Trip switch to the Close position, or press the Close pushbutton. There should be both the sound of the breaker closing and indication that the breaker contacts are closed by the main contact status indicator.

High Potential tests employ hazardous voltages.

Will cause death or serious injury.

2. As soon as the breaker has closed, the automatic spring charging process is repeated.

3. After a satisfactory close operation is verified, move the breaker Close/Trip switch to the Trip position, or press the Trip pushbutton. Verify by both sound and contact position that the contacts are open. Completion of these checks demonstrates satisfactory operation of auxiliary switches, internal relays and solenoids.

4. For breakers equipped with the external emergency trip knob (red knob on exterior of breaker), close the breaker and then use (pull) the emergency trip knob and verify by both sound and contact position that the contacts are open.

For breakers not equipped with electrical close and trip switches, perform the above checks by utilizing the remote control close and trip signals.

Checks Of Spring Charging Motor - No additional checks of the spring charging motor are necessary. Once every 10,000 operations, the motor brushes need replacement (reference kit 18-658-612-886). Use the operation counter as the basis for establishing the operation frequency.

High Potential Tests

The next series of tests (Vacuum Integrity Test and Insulation Tests) involve use of high voltage test equipment. The breaker under test should be inside a suitable test barrier equipped with warning lights.

Vacuum Integrity Check - A high potential test is used to verify the vacuum integrity of the circuit breaker. This test is conducted on the circuit breaker with its primary contacts in the Open position.

Vacuum interrupters may emit X-radiation. Can cause serious injury.

X-rays can be produced when a high voltage is placed across two circuit elements in a vacuum.

Keep personnel more that six (6) feet away from a circuit breaker under test. All normal metallic doors and panels must be installed during tests.

High Potential Test Voltages - The voltages for high potential tests are shown in Table 4.

Table 4. High Potential Test Voltages

Rated

Maximum

Voltage

kV (rms)

15.5

25.8, 27.6

Power Frequency Withstand

kV (rms)

50 60

Field Test Voltage

kV (rms) kV (dc)

37.5 45

63.6

Note: Do not use DC high potential testers incorporating half-wave rectification. These devices produce high peak voltages.

These high voltages will produce X-ray radiation. These devices also show erroneous readings of leakage current when testing vacuum circuit breakers.

Maintenance

Vacuum Integrity Test Procedure

1. Observe safety precautions listed in the danger and caution advisories. Construct the proper barrier and warning light system.

2. Ground each pole not under test.

3. Apply test voltage across each pole for one (1) minute.

4. If the pole sustains the test voltage for that period, its vacuum integrity has been verified.

Note: This test includes not only the vacuum interrupter, but also the other insulation components in parallel with the interrupter. These include the standoff insulators and the insulated drive links, as well as the insulating (tension) struts between the vacuum interrupter (polehead) supports. If these insulation components are contaminated or defective, the test voltage will not be sustained. If so, clean or replace the affected components, and retest.

If DC high potential tests are used, note the following: If a DC test indicates loss of vacuum, reverse the polarity of the test leads and retest. If the second test is successful, the interrupter has adequate vacuum integrity. If the second test also indicates loss of vacuum integrity, replace the interrupter.

As-Found Insulation and Contact Resistance Tests - AsFound tests verify the integrity of the breaker insulation system. Megger or insulation resistance tests conducted on equipment prior to installation provide a basis of future comparison to detect changes in the protection afforded by the insulation system. A permanent record of periodic As-Found tests enables the Maintenance organization to determine when corrective actions are required by watching for significant deterioration in insulation resistance, or increase in contact resistance.

Insulation and Contact Resistance Test Equipment - In addition to the High Potential Test Equipment capable of test voltages as listed in Table 4, the following equipment is also required:

• AC High Potential tester with test voltage of 1125 volts,

60 Hz.

• Micro-Ohmmeter for contact resistance tests.

Insulation and Contact Resistance Test Procedure

1. Observe safety precautions listed in the danger and caution advisories for the Vacuum Integrity Check tests.

2. Close the circuit breaker. Ground each pole not under test. Use manual charging, closing and tripping procedures.

3. Apply the proper AC (i.e., either 37.5 or 45kV) or DC (i.e., either 53 or 63.6kV) high potential test voltage between a primary conductor of the pole and ground for one minute.

4. If no disruptive discharge occurs, the insulation system is satisfactory.

5. After test completion, ground both ends and the middle ring (if visible) of the vacuum interrupter to dissipate any static charges.

6. Disconnect the leads to the spring charging motor.

7. Connect all points of the operator terminal block (located on the right side of the operator frame) with a shorting wire. Connect the shorting wire to the high potential lead of the high voltage tester, and ground the breaker housing. Starting with zero volts, gradually increase the test voltage to 1125 volts, rms, 60 Hz. Maintain test voltage for one (1 ) minute.

8. If no disruptive discharge occurs, the secondary control insulation level is satisfactory.

9. Disconnect the shorting wire and reattach the leads to the spring charging motor.

10.Perform contact resistance tests of the primary contacts using a Micro-Ohmmeter. Contact resistance should not exceed the values listed in Table 5. Note, the contact resistance is measured across the phase terminals (outside terminals of roof bushings.)

Table 5. Maximum Contact Resistance

Current Rating

(Amps)

1200 150 2000 150

Contact Resistance

(Micro-Ohms)

11.Make a permanent record of all tests performed.

Maintenance

Inspection And Cleaning Of Breaker Insulation

1. Perform the Spring Discharge Check on the circuit breaker, after all control power is removed. The Spring Discharge Check consists of 1) depressing the Trip pushbutton, 2) then depressing the Close pushbutton, and 3) again depressing the Trip pushbutton. All of these controls are on the breaker operator front panel. Visually verify the Discharge condition of the springs.

2. Remove the phase barriers (when so equipped) as shown in Figure 10.

3. Clean barriers (when so equipped), post insulators and roof bushings using clean cloth and one of the following cleaning solvents:

• No. 1 or No. 2 denatured alcohol

• Isopropyl or isobutyl alcohol

4. Reinstall all barriers (when so equipped). Check all visible fasteners again for condition and tightness

Do not use any cleaning compounds containing chlorinated hydrocarbons such as trichlorethylene, perchlorethylene or carbon tetrachloride.

These compounds will damage the phenlylene ether copolymer material used in the barriers and other insulation on the circuit breaker.

Relays and Instruments

The breaker can be equipped with a relay panel when required. A relay package can be supplied on a hinged panel mounted in the front of the control compartment.

To insure satisfactory operation of relays and instruments do not leave device covers off longer than necessary. When a cover has been broken, cover the device temporarily and replace broken cover as soon as possible.

Refer to the wiring and schematic diagrams, and other instruction literature shipped with the breaker for additional specific relay requirements.

Equipment Surfaces

Inspect the painted surfaces and touch up scratches as necessary. ANSI-61 touchup paint is available from Siemens. This paint matches the unit and is thinned and ready for use in one pint (473mm3) spray cans.

Inspect interior of unit for entrance of moisture and repair as necessary.

Inspect ventilation filters, clean or replace as appropriate.

Functional Tests

Refer to the Installation Checklist in the Installation Checks and Initial Functional Tests section of this manual. Functional tests consist of performing at least three (3) Manual Spring Charging Checks and three (3) Automatic Spring Charging Checks. After these tests are complete, and the springs fully discharged, all fasteners and connections are checked again for tightness and condition before placing the breaker back in service.

Operator Adjustments

Vertical Edge

Eccentric

#10-32 Recessed

Hex Socket Set Screw with Locking Nut 66

Hazardous voltages and high-speed mechanical parts.

Will cause death, serious injury or property damage.

Read instruction manuals, observe safety instructions and limit use to qualified personnel.

The following adjustments are not required during routine maintenance of the breaker. These adjustments should be considered if:

1. The spring charging motor runs but does not advance the ratchet wheel (springs do not charge).

2. The breaker does not close and open in a normal manner and electrical control check out is satisfactory.

Before these adjustments can be made, the front panel of the operator must be removed to gain access to the adjustment points of the mechanism.

Spring Charging Adjustment - Figure 27

1. Remove the spring charging motor.

2. Install a 1/2 inch drive extension and ratchet wrench in the eccentric drive shaft.

3. Rotate the eccentric shaft until the eccentric is at its maximum inward position.

4. Adjust the hex socket set screw (66) until the driving surface of the upper pawl is approximately 0.031 inch from the face of the ratchet tooth.

5. Mount the spring charging motor and operate the charging system electrically. Adjust the hex socket set screw (66) until the ratchet moves with minimum noise.

6. Lock the set screw in position using the lock nut.

This completes the adjustment of the charging system mechanism.

Figure 27. Charging Adjustment.

Operator Adjustments

Spring Release Latch “Bite” Adjustment

1. Remove front panel of operator.

2. Find spring release latch adjusting screw located in the vertical flange of the operator (10-32 recessed hex socket set screw, see Figure 27).

3. Nominal latch bite adjustment occurs with the latch lying in the horizontal position as shown in accompanying Figure 28. This position is achieved when the ad- justing screw has been turned into the prevailing torque

Vertical Flange Left Hand

Mechanism Stanchion

Approximately 14 Turns of Adjusting Screw

Spring Release Rotation

self clinching nut 14 full turns.

The set screw will be within 1 to 2 turns of being flush to the self clinching nut, protruding slightly.

The adjusting screw should

not be advanced more than 16 turns. Four turns beyond the nominal 14 turns is sufficient to reach the “threshold” beyond which the spring release will occur and latch stability will be lost.

Spring

Release

Latch

Closing Spring

Hatchet

and Roller

1.390

1-2 T urns

.937

.000

.860

.420

(Spring

.000

Hex Socket Adjusting Screw

(#10-32 UNF-2A)

Note: All Dimensions

Shown In Inches.

Figure 28. Spring Release Adjustment Screw.

Release Latch

Thru Mechanism)

Spring Release

Shaft

Spring Release Interlock Lever

Overhaul

Introduction

The following procedures along with the troubleshooting charts at the end of this section, provide maintenance personnel with a guide to identifying and correcting possible malfunctions of the type SDV vacuum circuit breaker.

Hazardous voltages and high-speed moving parts.

Can cause death, serious injury, or property damage.

All replacement of breaker components must be performed with the breaker completely de-energized and the springs discharged.

Circuit Breaker Overhaul - Table 6 lists the recommended overhaul schedule for type SDV circuit breakers operating under ANSI usual conditions. When actual operation conditions are more severe, overhaul periods should occur more frequently. The counter on the front panel of the circuit breaker records the number of operations.

Table 6 Overhaul Schedule ANSI Usual Conditions Maintenance Based Upon Number of Closing Operations

Number of

Breaker Type

SDV-4A

Closing Operations

5,000

Replacement At Overhaul - The following components are replaced during an overhaul of the circuit breaker, when required:

• Vacuum interrupters as determined by vacuum integrity test, contact erosion, or after 10,000 operations.

• Spring charging motor brushes should be replaced after 10,000 operations (reference kit 18-658-612-886).

2096-98

Figure 29. Use of Socket Wrench to Release Tension on Closing Springs.

Replacement Of Closing Springs - Figure 29 shows the use of a 3/4 inch socket wrench to relieve spring tension on the closing springs. The bottom of the breaker operator frame has openings providing access to the tensioning bolts. Turning the left and right hand support bolts counterclockwise relieves spring tension. Alternate from the left bolt to the right bolt in small increments. This keeps the sliding cross arm relatively level as the tension is removed from the springs.

Each upper spring hanger is fastened to a crank arm using a hex socket shoulder bolt and nut. The nut is applied using thread locking adhesive, Loctite 271, with Loctite type T primer.

When springs are reinstalled, be sure the support bolts are inserted inside their support bolt bushings. These bushings maintain the correct tension on the closing springs. Replace all retaining rings during the re-assembly. Retighten by turning the support bolts counterclockwise, alternating sides to keep the crossbar approximately level, until the support bolt bushings firmly butt up against the support bolt attachment bracket and the cross arm support shaft.

Overhaul

Replacement Of Opening Spring - The opening spring may be removed and replaced without the need to use a spring keeper or compression aid.

The opening spring assembly consists of the top and bottom spring caps, threaded coupling rod with nuts, and a supporting shelf. The shelf features location holes and tabs which work in concert with supports in the breaker frame to secure the shelf.

An adjustable crescent wrench allows an easy means of grasping the shelf and depressing it slightly to disengage the tabs in the shelf locating holes. With the tabs disengaged, and grasping the bottom of the spring, the whole assembly can be pulled forward.

A reversal of this procedure allows re-assembly. Note that there should be at least two threads of the coupling rod visible above the jackshaft rod attachment (with jam nut tightened). After the opening spring assembly is reinstalled, the opening spring length should be adjusted to be 6.125”. This measurement is taken between the supporting shelf and the bottom of the lower spring cap (Figure 30).

When re-assembling, apply downward pressure to the shelf under the stationary support to engage the shelf tab guides. The shelf may then be guided into place.

Replacement Of Closing and Tripping Solenoids (Devices 52SRC and 52T) - Replacement of either the closing or trip-

ping solenoids is straightforward. Each solenoid has two mounting screws and one quick disconnect terminal. Removing the mounting bolts and quick disconnect terminal of the solenoid permits it to slide out and to be removed. Replacement requires careful insertion of the solenoid and re-attachment of the mounting bolts and quick disconnect. Figure 31 shows the two screws which attach the close coil and the quick disconnect terminal for control leads. The trip coil arrangement is similar.

Mounting Bolts

Quick Disconnect

2098-98

Figure 31. Replacement of Closing Solenoid.

Replacement of Anti-Pump Relay (Device 52Y) - Figure 32

helps illustrate the anti-pump relay removal procedure. The two nuts holding the relay and its mounting bracket are removed. The wires connected to the relay should be tagged and disconnected, the relay and bracket can then be extracted and replaced.

Replacement of the Auxiliary Switch - Figure 32 shows the auxiliary switch and its key mounting components. Two mounting screws hold the switch to the mounting bracket. First remove the quick disconnect terminals after marking their position. The screw, washers and nut connecting the switch operating lever to the operating shaft is removed, and then the two mounting screws. Re-assemble in reverse order.

Figure 30. Removal of opening spring.

Overhaul

Replacement of Motor Cutoff Switch (Device LS1) and Spring Charged Switch (LS2) - The motor cutoff switch

(LS1) and spring charged switch (LS2) form a common assembly of two switches on one mounting bracket. Should either switch require replacement, it is recommended that both be replaced as a single assembly. The motor cutoff switch (LS1) is the “outboard” device with respect to the mounting bracket. Removal of the two mounting screws shown in Figure 33 allows both switches to be brought out for convenient removal of the interconnecting wiring.

Next, mark all wires to both switches. Remove the wires. Then replace the switches, rewire, and reassemble the switches to their mounting bracket. Be sure to use the same flat washer, lock washer and nut configuration in reassembly as was present in the as-shipped condition.

Wires to the switch must be marked and removed. The stop plate and switch may then be removed as a subassembly. The switch is a bushing type, for panel mounting, and threads into the stop bracket. After adjustment, it is secured by a jam nut and locking nut.

Adjustment requires the trip of the switch plunger to be set 0.06-0.09” ahead of the stop bracket tab, as illustrated in Figure 34. Secure the switch, position the stop bracket assembly, and reattach the wires. Install the 3/8” nuts to secure the trip shaft actuator stop plate to the mechanism. Remount the trip shaft actuator.

Confirm that the switch is vertically aligned to ensure that it will not be struck by the closing hatchet or the trip shaft actuator.

2092-98

Figure 32.

Replacement of Trip Latch Reset Check Switch (Device LS3)

- The trip latch reset check switch (LS3) is mounted on the

trip shaft actuator stop plate, as shown in Figure 35. To replace this switch, the trip shaft actuator must be removed by backing out two 10-32 hex socket screws, and then removing two 3/8” nuts which secure the trip shaft actuator stop plate to the mechanism.

Replacement of Anti-Pump Relay or Auxiliary Switch.

2102-98

Figure 33. Motor Cutoff Switch (LS1) and Spring Charged Switch (LS2).

2101-98

Figure 34. Trip Latch Reset Switch (LS3).

Overhaul

Replacement of Enindine Damper Assembly (see Figure

26) - Damper replacement will require the removal of a pin

which ties the damper mounting yoke to the circuit breaker operator frame. Refer to Figure 35a.

The damper is attached to the mounting yoke with a lock washer and 5/8-18 jam nut. For added security, the jam nut is treated with a thread locking adhesive (Loctite 271 with Loctite type T primer), and then torqued to a value of 17-20 ft-lbs.

Check all associated parts, damper body and telescoping tube, for wear. Replace as necessary.

The telescoping tube and internal striker block employ slugs in variable thicknesses and quantity to control movable contact motion. If the telescoping tube is replaced, the tube must be replaced with the correct tube to assure that the correct type and number of slugs are present.

Replacement of Liner Decelerator (shock absorber) (see Figure 26) - For replacement of this type of shoch absorber,

refer to Figure 35b and implement the following steps: Loosen the jam nut on the body of the shock absorber and remove the retaining rings from the ends of the pin located below the shock absorber. Remove the pin — capture the spacers and washers. Remove the shock absorber, jam nut, star washer and adapter from the shock absorber tube. (Note — the spacer which is trapped between the shock absorber and the adapter should be kept with the adapter). Set the new shock absorber setting to Position 8. tighten the set screw to 6 in. lbs. Thread the jam nut on to the shock absorber body, install star washer and thread the body of the shock absorber into the adapter. Continue to thread in until the shock absorber bottoms out on the spacer inside the adapter. Place the body of the shock absorber into the tube and fit the adapter into the breaker channel. Align holes, add spacers and washers to center the shock absorber and the tube, and secure with pin and retaining ring. Tighten the jam nut.

Recommended Hand Tools

Figure 35a. Figure 35b.

Replacement of Spring Charging Motor (Device 88) - Re-

move the quick-disconnect terminals. Then remove the screws holding the motor mounting bracket to the breaker housing. The motor slips out as a complete assembly. Check and replace as required.

Note: Special care needs to be exercised in removal of hardware around the movable contact end of the vacuum interrupter.

The movable contact uses a metal bellows assembly to maintain the vacuum seal while still permitting in and out motion of the contact. This bellows assembly is rugged and reliable, and is designed to withstand years of horizontal movement. However, care should be exercised in subjecting the bellows to excessive torque during removal and replacement. Twisting the bellows through careless bolt removal or tightening may damage the vacuum interrupter.

Index of Figures and Tables

Vacuum Tube

Family

VS17006 15.5kV, 1200 Amp 37 VS25008 15.5kV, 2000 Amp 38 VS25008 25.8kV, 1200 and 2000 Amp 39

Breaker Side Elevation (Typical) 36 Tube Clamp Fastening

Procedure / Stroke Adjustment 40

Voltage and

Continuous Current Pole Unit Assembly

Figure

Replacement of Vacuum Interrupters

The following procedures are for the removal and replacement of the vacuum interrupters.

Reference Tables and Lists

Fastener Torque Limits Table 7

Overhaul

Open End or Box End Wrenches:

• 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, and 7/8 in.

Socket Wrenches: (1/2” drive preferred)

• 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, and 7/8 in.

• 18, 19 and 24mm (deep sockets)

• Ratchet

• 2 Extensions (6” maximum)

• Torque Wrench (0-150 ft-lbs.)

Hex Keys Wrenches: (socket type preferred)

• 3/16, 1/4 and 5/16 in.

• 8 and 10mm

Miscellaneous:

• Screw Drivers: 0.032 x 1/4 in. wide and 0.055 x 7/16 in. wide

• Pliers

• Hot Air Gun

• “Loctite” Threadlocker 242

• “Loctite” Primer T

Preparation

Identify tube family, and breaker voltage and continuous current rating. The tube will have an identifying nameplate showing the family designation, the breaker voltage and continuous current rating can be taken from the breaker rating label. Note the VS17006 vacuum interrupter can be identified by its insulating shrink tube which covers the nameplate.

Check the “Index of Figures” to find the appropriate side elevation picture of the breaker pole unit assembly. Confirm that the figure applies by comparing the figure carefully to the breaker.

Read through the replacement procedures, noting recommended tools, gauging requirements and torquing limits. etc.

Vacuum Interrupter Removal

Before starting work, be sure that the operator springs have been discharged and the breaker is open.

4. Remove the two snap rings from either end of the pins of the pivot block. With a large flat bladed screwdriver, pry the lever arms from the pivot block. Grasp and pull the coupling rod toward you with one hand while prying the lever off the pin, first on one side, then on the other side of the pivot block. Once both levers are free from the pivot block pins, the levers will be pulled down abruptly due to the vacuum pulling the interrupter closed.

5. Locate the small pin passing through the levers and the eye of the rod end bearing of the interrupter. Remove the two snap rings from the ends of this pin and push the pin out through the side openings of the polehead. Retain the pin, spacers and snap rings for later use.

6. Loosen the jam nut on the rod end bearing. Remove the rod end bearing by turning counterclockwise.

7. Refer to Figure 40, and using the procedure shown to secure head and nut proceed to loosen the bolts which fasten the flexible shunt clamp to the movable contact of the interrupter. Remove shunt clamp hardware, set aside for reinstallation later.

8. Check the clamp on the movable contact to ensure that it will slide freely from the interrupter movable stem. The clamp may have to be wedged or worked open in order to slide freely from the interrupter.

9. Remove the cap screw(s) (may be three or one depending on design) in the stationary end of the interrupter. Move the stationary end of the interrupter sideways until it is clear of the polehead and withdraw the interrupter.

Vacuum Interrupter Replacement

10. Inspect all silver plated surfaces for cleanliness. Wipe clean with solvent and clean rag. Do not abrade. Inspect the replacement interrupter for evidence of damage such as dents, cracks or chips. Manually pull on the moving terminal of the interrupter to check vacuum integrity; there should be a noticeable resistance to movement (approximately 20 lbs.).

1. Repeat the spring discharge check described in the section entitled Installation checks and Initial Functional Tests.

Primary tasks of this check are:

1.1. De-energized the breaker control power.

1.2. Press the Trip pushbutton followed by the Close

pushbutton followed by the Trip pushbutton again.

1.3. Verify the Spring Condition Indicator shows DIS-

CHARGED and the Main contact Indicator shows OPEN.

2. Make provisions to save and retain hardware. Rejoin fastener parts (bolts, nuts, washers, lockwashers, etc.) as they are removed. Save in an appropriate container.

3. Remove the phase barriers (when so equipped) from the high voltage compartment for easier access to the interrupters. Set aside for reinstallation later.

11. Unless the vacuum interrupter replacement kits contains a new copper spacer and associated mounting hardware, the spacer (when so equipped) and associated mounting hardware removed with the vacuum interrupter will be reused. Handle spacers carefully protecting the flat contact surfaces. Make sure contact surfaces are wiped clean prior to installation. If the spacer is attached to the old interrupter, remove it and attach it to the new interrupter.

Note: Stationary contact is annealed copper.

Thread damage will occur if threads are crossed. Be sure the bolt(s) can be fully engaged with light manual torque.

Overhaul

12. Position the interrupter with the slot in the moving terminal uppermost and slide the moving terminal through the plastic support ring on the large polehead. Move the stationary end of the interrupter (with copper spacer when so equipped) into position on the small polehead and install the cap screw(s) (may be three or one depending on design) into the interrupter finger tight only.

13. Check the end of the interrupter at the large polehead to be sure that the body of the interrupter is supported in the plastic ring. This is a snug fit and may require a slight twisting motion.

14. Torque fastener(s) at the interrupter stationary contact to firm the interrupter stationary contact against the small polehead, using torque shown in Table 7. The compan- ion lock washer is to be fully collapsed. Hold interrupter in the alignment required under Step 11 of vacuum interrupter replacement procedure while tightening this fastener(s).

15. Slip the flexible shunt clamp over the movable contact stem of the interrupter. Care must be taken to avoid applying any twisting or bending forces to the movable contact stem as this could cause premature bellows failure. Replace clamp hardware; bolt(s), washer(s), and nut(s). Position the clamp firmly against the shoulder on the terminal and tighten hardware firmly. Check to be sure the shunt clamp is positioned vertically and has adequate clearance on both sides. If the clamp is tilted, reposition vertically and retighten using torque shown in Table 7.

Note: Check to be certain the interrupter clamp has been positioned against the movable stem step before securing the clamp.

shown in Table 7. When properly installed, the rod end bearing will be in a vertical position.

20. Remove the small pin and reassemble with the spacers and snap rings removed in Step 4. Be sure the snap rings are firmly seated in their grooves. Replace the rings if they are bent or feel loose after installation.

21. With the 0.250 inch drill rod in place, push the coupling rod assembly into firm contact with the operating levers. While maintaining this position, check to see that the top of the coupling rod (bottom of pivot block) is flush with the top of the operating levers. This is the correct adjustment of the coupling rod.

22. If the coupling rod (pivot block) is higher or lower than the top of the operating levers, the coupling rod must be readjusted. Locate the LOWER end of the coupling rod, where it attaches to the operator jackshaft levers. The threaded stud of the coupling rod passes through a threaded hole in the jackshaft lever pin, and has a jam nut above and below the lever pin. Loosen the upper and lower jam nuts to permit the rotation of the coupling rod. These parts have been assembled using a threadlocking adhesive and will have some resistance to turning.

23. Adjust the coupling rod as follows: a. If the coupling rod extends above the top surface of

the operating levers, turn the coupling rod clockwise until the surfaces are flush.

b. If the coupling rod is below the top surface of the op-

erating levers, turn the coupling rod counterclockwise until the surfaces are flush.

c. Apply fresh serviceable threadlocking adhesive Loctite

242 to the threads between the jam nuts and the jackshaft pin. Tighten the jam nuts securely.

16. Thread the jam nut onto the rod end bearing as far as it will go, and then screw the rod end bearing into the moving terminal approximately half way. Do not tighten at this time.

17. Place a 0.250 inch drill rod or No. 2 Phillips screwdriver through the rig pin hole in the side of the polehead. Pass the rod through the slots in the levers and then through the rig pin hole in the opposite side of the polehead. This locks the levers in a fixed position for adjusting the drive mechanism.

18. Push the small pin removed in Step 4 through the open hole in a lever, through the rod end bearing, and through the other lever. If the holes do not line up to permit this, the rod end bearing must be screwed in or out until the pin passes freely through both levers and the rod end bearing. Use care in this adjustment. The pin must pass through all three holes with a light pressure by hand.

19. Maintain the position of the rod end bearing while tightening the jam nut against the terminal end using torque

24. Remove the drill rod from the large polehead.

25. Twist the pivot block so that the axis of the block pins approach the axis of the lever holes at approximately 45°. Manually raise the levers. When the lever hole is aligned with the most forward pin, push on the coupling rod to lock that lever in position. Apply pressure while prying the other lever outward to pass over the other pin. As the last pin passes between the levers, the first pin will snap into its hole. The second lever may have to be raised or lowered to align with its hole. Replace the snap rings on the ends of the pivot block pins.

26. This completes the installation and adjustment of the interrupter. Operate the breaker manually several times and recheck all fasteners to assure that they are properly installed or tightened.

27. Replace the phase barriers (when so equipped) removed in Step 2.

28. Perform High Potential Test across open vacuum interrupter and from each primary connection to ground (See Table 4 on page 26).

Overhaul

Table 7: Critical Fasteners and Torque Limits

Interrupter

Family

Stationary Contact Movable Contact

Interrupter Clamp

TorqueSizeTorqueSizeTorqueSize

VS17006

VS25008

M12

M16

45-50 ft-lbs.

61-68 N-m

60-65 ft-lbs.

81-88 N-m

M10

M12

15-20 ft-lbs.

20-27 N-m

15-20 ft-lbs.

20-27 N-m

M10

26-35 ft-lbs.

35-47 N-m

26-35 ft-lbs.

35-47 N-m

Figure 36. SDV Breaker Side Elevation (Typical).

Figure 37. VS17006 15.5kV, 1200 Amp.

Overhaul

Figure 38. VS25008 15.5kV, 2000 Amp, & 25.8/27.6 kV, 2000Amp.

Figure 39. VS25008 25.8/27.6kV, 1200 Amp.

Figure 40. Tube Clamp Fastening Procedure / Stroke Adjustment.

Overhaul

Periodic Maintenance and Lubrication Tasks

Sub-Assembly

Item

Inspect For

Primary Power Path

Interrupter Operator Mechanism

Electrical Controls

Vacuum Interrupter

Cleanliness

Fasteners

Manual Spring Check

Lubrication

Wiring

Terminals and Connectors

1. Cleanliness

2. Contact erosion Note: Perform with Manual Spring Checks

3. Vacuum integrity Note: Perform with High Potential Tests

1. Dirt or foreign material

1. Tightness of nuts and other locking devices

1. Smooth operation of manual charging, and manual closing and tripping

1. Evidence of excessive wear

2. Lubrication of wear points

1. Mechanical damage or abrasion

1. Tightness and absence of mechanical damage

High Potential Test

Insulation

Close and Trip Solenoids, Anti-Pump Relay, Auxiliary Switches

Spring Charging Motor (88)

Primary Circuit to Ground

Control Circuit to Ground

Vacuum Interrupter Contact Resistance

Barriers and all Insulating Components

1. Automatic charging

2. Close and trip with control power

1. Replace brushes after 10,000 operations

1. 60 second withstand, 37.5 or 45kV, 60 Hz (53 or 63.6kV DC) (depending upon voltage rating of breaker - refer to Table 4)

1. 60 second withstand, 1125V, 60 Hz

1. Record contact resistance with contacts closed, and recheck each maintenance interval to monitor condition

1. Cleanliness

2. Cracking

Overhaul

Troubleshooting

Problem

Symptoms

Possible Causes and Remedies

Breaker fails to close 1. Secondary control circuit is

Closing springs will not automatically charge.

Closing springs charge, but breaker does not close.

• Closing coil, or solenoid (52SRC) fails to energize. No sound of breaker closing

de-energized or control circuit fuses are blown. Check and energize or replace if necessary.

2. Damage to wiring, terminals or connectors. Check and repair as necessary.

3. Failure of charging motor (88). Check brushes and replace if required.

4. Motor cutoff switch (LS1) fails to operate. Replace if necessary.

5. Mechanical failure of operating mechanism. Refer to factory or authorized service shop.

1. Secondary control circuit de-energized, or control circuit fuses blown. Correct as indicated.

2. No closing signal to TB4. Check for continuity and correct relay logic.

3. Failure of anti-pump relay (52Y) contacts 21-22 or 31-32 or 13-14. Check and replace as required.

4. Failure of close coil (solenoid) (52SRC). Check and replace as required.

5. Auxiliary switch NC contacts 3-4 are open when breaker contacts are open. Check linkage and switch. Replace or adjust as necessary.

6. Spring charged switch (LS2) NO contact remains open after springs are charged. Check and replace as required.

• Closing coil, or solenoid (52SRC) energizes. No sound of breaker closing

• Closing coil energizes. Sound of breaker closing is heard, but breaker contacts do not close.

1. Check close latch position. Repair or adjust as necessary. See spring release latch “bite” adjustment, page 30.

1. Mechanical failure of operating mechanism. Check and contact factory or authorized service shop.

Overhaul

Troubleshooting

Problem

Nuisance or false close

Circuit breaker will not trip

(continued)

Symptoms

Electrical problem

Mechanical problem

Tripping coil, or solenoid (52T) does not energize. There is no tripping sound.

Possible Causes and Remedies

1. Nuisance or false closing signal to TB4. Check relay logic. Correct as required.

2. Closing coil (52SRC) terminal 2 is shorted to ground. Check to determine if problem is in wiring or coil. Correct as required.

1. Mechanical failure of operating mechanism. Check and contact factory or authorized service shop.

1. Secondary control power is de-energized or control power fuses are blown. Correct as indicated.

2. Damage to wiring, terminals or connectors. Check and repair as necessary.

3. No tripping signal to TB7. Check for continuity and correct relay logic.

4. Failure of trip coil (52T). Check and replace if necessary.

5. Auxiliary switch NO contacts 1-2 or 5-6 are open when breaker is closed. Check linkage and switch. Replace or adjust as necessary.

Nuisance or false trip

Tripping coil (52T) energizes. No tripping sound is heard, and breaker contacts do not open (i.e., they remain closed).

Tripping coil (52T) energizes. Tripping sound is heard, but breaker contacts do not open.

Electrical problem

Mechanical problem

1. Failure of tripping spring or its mechanical linkage. Check and replace if required.

1. Mechanical failure of operating mechanism. Check and contact factory or authorized service shop.

2. One or more of the vacuum interrupters are held closed. Check and replace as necessary.

1. Tripping signal remains energized on TB7. Check for improper relay logic.

1. Mechanical failure of operating mechanism. Check and contact factory or authorized service shop.

Overhaul

Ordering Replacement Parts

When ordering replacement parts for a Siemens Power Circuit Breaker, it is very important to give complete information. This information should include:

1. Breaker serial number. (On breaker nameplate.)

2. Type of operator. (On operator nameplate.)

3. Type of breaker.

4. Rated continuous current of breaker.

5. Rated voltage of breaker.

6. Description of part. Use instruction book description insofar as possible.

7. Instruction book number. (On breaker nameplate.)

8. Instruction book reference number.

9. Number of pieces required.

While the breaker can be identified by the serial number alone, all additional information that is given will serve as a check to be certain that the part or parts furnished are correct for the breaker in question. Without this serial number, Siemens cannot be sure of the correct identity of the desired parts.

If any doubt exists as to the instruction book reference number or the description, a dimensional sketch of the desired part will help to properly identify it.

Siemens recommends that a supply of repair parts be kept on hand so that emergency repairs can be made without waiting for shipment of parts from the factory. A list of recommended spare parts is sent with the breaker. Before removing any part to be replaced, observe its function and adjustment. This usually saves adjustment time during installation.

Appendix

Table A-1

Type SDV Ratings

Type Definition: SDV-4A (Generic for SDV4), followed by Rated Maximum Voltage (kV), followed by Rated Short Circuit Current (kA)

Ratings

Rated

Closing

and

Latching

Current

kA,peak

Circuit

Breaker

Type

SDV-15.5-20

SDV-15.5-25

SDV-25.8-20

SDV-25.8-25

SDV-27.6-20

SDV-27.6-25

Rated

Maximum

Voltage

kV,rms

15.5

25.8

27.6

Rated

Voltage

Range Factor

1.0

Rated

Continuous

Current

Amperes,

A,rms

1200 2000

Rated ShortCircuit

and

Short-Time

Current

kA,rms

Rated Transient

Recovery Voltage

Rated

Peak

Voltage E

kV,peak

48.5

Rated Time to Peak T

µs

Rated

Interrupting

Time

ms/cycles

83/5

Rated

Permissible

Tripping

Delay

Time Y

sec

1. Maximum voltage for which the breaker is designed and the upper limit for operation.

2. Current values in this column are independent of operating voltage up to and including rated maximum voltage.

3. Assymmettical interrupting capability is in accordance with ANSI/IEEE C37.04-1999 with % dc component = 48%.

Table A-2

15.5kV and 25.8kV Type SDV Circuit Breaker Control Data Typical Spring Release (Close Coil), Trip Coil and Spring Charging Motor Characteristics

Control Voltages, ANSI C37.06 Table 8

Nominal

48 VDC

125 VDC

250 VDC

120 VAC

240 VAC

1. Current at nominal voltage. 2. 10A for coils mid-1993 and later. For coils supplied up to mid-1993, current is 23A.

90-140

180-280

104-127

208-254

Range

Close Trip Amperes

36-56

28-56

70-140

140-280

104-127

208-254

Close Coil

(2)

(1)

Trip Coil

Amperes

(2)

—

(1)

Run (Avg.)

Spring Charging Motor

Amperes

(1)

8.5

2.7

1.3

3.3

1.7

Inrush (Peak)

—

10.6

7.1

Charging

(1)

Seconds

Table A-3

Interrupting Capacity Auxiliary Switch Contacts

Type Auxiliary Switch

Breaker Auxiliary Switch

Continuous Current

Amperes

Control Circuit Voltage

120 VAC

20 20 20 10 2

240 VAC

Non-Inductive Circuit Interrupting Capacity in Amperes

Inductive Circuit Interrupting Capacity in Amperes

48 VDC 125 VDC 250 VDC

Appendix

Table A-4 Circuit Breaker Weights

Breaker Type

SDV-4A

Continuous Current, Amperes

1200 A 2000 A

Table A-6 Specifications

ITEM

Lightning Impulse Withstand Voltage

Full Wave 1.2/50 µsec kV 110 150 Chopped wave 2 µsec Chopped wave 3 µsec

Rated Making Current kA 20/25 20/25

Rated Normal Frequency cycles 60 60

Capacitance Switching

Overhead Line A 100 100

Isolated Current A 400 400

Back to Back A 400 400

Closing Time (max) ms 50 50

Trip Time (max) ms 37.4 37.4

Normal Operating Temperature Range

Phase Spacing (Bushing Center to Center) in/mm 15.0/591 15.0/591

Dual Trip Coils (mech. and elec. independent) — Optional Optional

Operating Mechanism - type GMI — Stored Energy Stored Energy

Standard - SDV-4A (IEEE STD 693-1997) g Moderate (0.25) Moderate (0.25)

Optional - SDV-4A (IEEE STD 693-1997)

Standard °C -30 -30

Special °C -40 -40

Contact Gap

1200A in/mm 0.28-0.35/7-9 0.59-0.63/15-16 2000A in/mm 0.59-0.63/15-16 0.59-0.63/15-16

External Creep

Standard in/mm 11/279.4 17/431.8

Special in/mm 17/431.8 26/660.4

External Strike to Ground

Standard in/mm 6/152.4 7.5/190.5

Special in/mm 7.5/190.5 10.5/266.7

Breaks per Phase — 1 1

Auxiliary Voltage VDC 48/125/250 48/125/250

Trip and Close Coil Rating VDC 48/125/250 48/125/250

Interrupting Medium — Vacuum Vacuum

Emergency Trip — Standard Standard

Minimum Reclosing Time

RIV 1000kHz µv less than 500 less than 650

Rated Duty Cycle — CO-15 sec-CO CO-15 sec-CO

Seismic Withstand

Weight, lbs.(kg)

Table A-5 Heater Data

Location

High Voltage Compartment

Control and Mechanism Compartment

2500 (1134)2400 (1089)

UNIT

kV 142 194 kV 126 172

VAC 115/230 115/230

sec 0.3 0.3

g High (0.50) High (0.50)

Low Temperature (Special -40°C)

1. Thermostat controlled and set to turn off at 95°F.

2. Thermostat controlled and set to turn off at 10°F.

SDV-15.5

O-0.35-CO-15 sec-CO O-0.3sec-15sec-CO

SDV-25.8 / SDV-27.6

Wattage

(1)

200

100

(2)

250

1 Breaker in closed position only. 2 Requires “X” bracing on circuit breaker legs. 3 User must supply external time delay to assure minimum reclose time interval of 0.3 seconds.

Siemens Power Transmission & Distribution Inc.

P.O. Box 29503 Raleigh, NC 27626-0503

SGIM-3788F (Replaces SGIM-3788D) (2-03) Printed in U.S.A.

SIEMENS is a registered trademark of Siemens AG.

Siemens SDV-4A Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual