Medium-voltage vacuum roll-in replacement circuit breakers
Vacuum roll-in replacement circuit breakers provide a cost effective way to upgrade your system capabilities while saving you from costly maintenance and lost productivity.
Whether your original air-magnetic switchgear was made by Allis-Chalmers, Westinghouse, GE, Federal Pacific, ITE, McGraw Edison, or another manufacturer, we will assist you to evaluate the Siemens vacuum replacement, retrofit, or retrofill option that best meets your needs.
Why replacement circuit breakers?
Increased reliability and performance
Reduced operating and maintenance expenditures
Reduced downtime and minimal changeover time during power switchgear modification or conversion
Preserved investment in existing cubicles
Improved employee and environmental safety.
Superior performance and longer service life
Standard 3AH operator on all Siemens replacement medium-voltage distribution and outdoor vacuum circuit breakers
MOC-Saver™ provides reliable operation of existing MOC system (applicable models)
Extensive replacement circuit breaker and retrofit experience with more than 800 projects since 1983
Nuclear 1E rated
Testing per ANSI, IEEE C37.59 - 2007
Full range of service capabilities by skilled factory-trained engineers and technicians.
Watch the videos below to learn more about medium-voltage replacement circuit breakers.
The following circuit breakers are available as pre-engineered designs. Other manufacturers, models, and ratings can be engineered by Siemens.
Live-tank circuit breaker support capabilities
Siemens has replacement circuit breaker designs for most Allis-Chalmers designs including the MA, MB, MC, MCV (Siemens MSV), FA, FB, FC, FCV (FSV), and AM (AMR). Siemens also has many designs for the GE Magneblast, Westinghouse DH/DHP, ITE HV/HK, Federal Pacific DST2, and McGraw Edison PSD.
Medium-voltage replacement circuit breaker sample specifications
Medium-voltage vacuum replacement circuit breakers should operate identically to the original circuit breakers including, but not limited to, operation of all Mechanism-Operated Control (MOC) auxiliary switches, Truck-Operated Control (TOC) auxiliary switches, test position operation, and all safety related functions.
Sample Replacement Specification
A. This Specification covers requirements for the replacement of air magnetic or oil circuit breakers to vacuum circuit breakers.
B. It is the intent of this Specification that the new circuit breaker operates identically to the original received breakers to include, but not limited, operation of all Mechanism-Operated Control (MOC) auxiliary switches, Truck-Operated Control (TOC) auxiliary switches, test position operation, and safety related functions. Siemens MOC-Saver system shall be used for reliable MOC operation.
C. It is the intent of this Specification that the new circuit breaker’s capabilities meet performance levels defined in published standards.
D. All equipment and parts shall meet the requirements of the latest applicable published standards of IEEE, NEMA, and ANSI including ANSI C37.09.
E. In all instances throughout this Specification, the term “Bidder” shall refer to a company submitting a proposal to fulfill the requirements of this Specification. The term “Seller” shall refer to the successful Bidder who is awarded the purchase order and who has accepted the overall responsibility for filling the requirements of this Specification.
F. Whenever equipment proposed by the Bidder cannot satisfactorily meet the intent of this Specification in any respect, such exceptions shall be clearly stated by the Bidder.
G. The Seller shall have full responsibility for compliance with the requirements of this specification. Review and/or approval of drawings or data does not constitute acceptance of any designs, materials, or equipment that will not fulfill the functional or performance requirements established herein.
H. The circuit breakers will be replaced over a period of ____________ days / months / years.
I. Each bid shall include the following:
1. The price of each circuit breaker replacement.
2. A proposed schedule detailing the sequence of breaker replacements and their required durations as described in the Specification.
II. TYPICAL BREAKER DATA
A. Air Magnetic circuit breakers to be replaced:
4. Continuous Current Rating:
5. Interrupting Class:
III. OUTLINE OF WORK
The work under this section consists of furnishing all labor, material, and equipment necessary to complete the work described. All new materials used shall be first quality and the best of each class and shall meet with the recommendations and standards of the various engineering and manufacturing associations. The replacement shall be in accordance with the most recent draft of the ANSI Standard C37.09 in all regards except required testing that is described in Section IV of this Specification.
A. The replacement circuit breaker shall be completely new. No used material will be allowed.
B. All breakers shall have Siemens vacuum interrupters.
C. A new, complete vacuum circuit breaker assembly (type Siemens 3AH) shall be used.
D. The breaker closing springs are to automatically discharge upon moving the breaker into the disconnect position.
E. Breaker open and close semaphore shall be red for close and green for open.
F. Manual trip and close handles shall be identified as “trip” and “close.”
G. The vacuum breaker assembly’s secondary control terminals and auxiliary terminals shall be wired to the secondary disconnect contacts the same as existing breaker to form a control circuit that is identical in all respects to the original received control circuits. All control wiring shall be a minimum of #16 AWG stranded, tinned type SIS wire and shall terminate with crimp-type lugs (Burndy Type VAV or approved equal). All contact ratings shall be greater than or equal to the original manufacturer’s nominal ratings. Nominal voltage of all related devices is.
H. All mechanical and electrical interlocks shall be the same as the existing circuit breaker. The replacement breaker shall not alter the operating characteristics of the existing mechanical and electrical interlocks. Bus connections between the vacuum breaker assembly shall be insulated phase-to-phase and phase-to-ground to maintain the original BIL or greater.
I. The operating mechanism shall be mounted to the front of the breaker frame assembly for ease of access and maintainability. All mechanism functions such as stored energy control and breaker tripping and closing shall be accessible from the front.
J. An operation counter shall be provided to register one count for each trip operation. It shall be visible from the front of the breaker.
K. The circuit breaker shall be completely assembled and wired in preparation for inspection and testing.
L. The completed replacement breaker shall be identical in electrical and physical functions to the received breakers except where enhanced safety interlocking is indicated.
M. The Seller shall provide a factory representative who, with the assistance of the Purchaser’s personnel, shall be responsible for the circuit breaker installation to include any required adjustments.
N. At the time of installation, the Seller shall train the Purchaser’s personnel on the converted breaker’s operation and maintenance.
Testing shall be in accordance with the latest ANSI Standards and the most recent draft of the ANSI Standard C37.09 in regards to the tests described in this section.
The Purchaser reserves the right to witness factory tests and is to be notified at least 10 days prior to these tests.
A. Vacuum Breaker Retrofit Elements
The vacuum breaker elements shall be design tested and certified to meet the latest applicable ANSI, NEMA, and IEEE standards. Certified design tests shall be submitted in accordance with Section 6 of this Specification. Each breaker element shall be of current manufacture and be fully production tested in accordance with ANSI C37.09, Section 5.
B. Completed Vacuum Circuit Breaker Replacement
1. Required Design Tests
Complete set of IEEE design tests are to be performed on a completed prototype unit. The prototype unit shall pass these tests before any additional breakers are built. If these tests have already been performed on an identical unit, certified copies of these test reports shall be submitted. This includes but is not limited to:
a. Rated Full Wave Impulse Withstand Voltage Test as per ANSI C37.09, Paragraph 4.5.4.
b. Low Frequency Withstand per ANSI C37.09, Paragraph 188.8.131.52
c. Mechanical Endurance Test as per ANSI C37.20.2. The Seller shall not perform this test except at the direction of the Purchaser.
d. Rated Continuous Current Test as per ANSI C37.09, Paragraph 4.4
e. Close and Latch as per ANSI C37.09, Paragraph 184.108.40.206 and ANSI C37.06 - Table 1
2. Production Tests: The following production tests shall be performed on all replacement units:
a. AC High Potential (HI POT) test to test the breaker’s dielectric strength. The HI POT test voltage will be supplied by the Purchaser prior to the test. High voltage insulation will be checked phase-to-phase, phase-to-ground, and line-to-load.
b. Mechanical Operating Test as described in C37.09, Paragraph 5.11, to include the verification of all mechanical and electrical interlocks.
c. Measure and submit the primary circuit path resistance for each pole of the breaker.
A. Four (4) copies of the complete inspection report with all test results and data sheets shall be provided for the breakers.
B. Four (4) complete sets of breaker schematic wiring drawings shall be provided which show the secondary control block, the close and trip coils, the various breaker switches and contacts, and other electrical components of the breaker.
C. Four (4) complete sets of instruction manuals shall be provided with the breaker.
D. One (1) copy of documentation shall be shipped with the shipment of replacement breaker(s).
The Seller shall warrant that the equipment and all parts shall be free from defects in design, manufacturing, and material. The warranty shall extend for a minimum of one (1) year after commercial operation or eighteen (18) months from delivery. If, during the warranty period, modifications or repairs of the subject equipment are necessary, the warranty period shall be extended for a minimum of one (1) year from the date of the completion of repair or modification.
Remote racking solutions
Siemens provides cost effective remote circuit breaker racking solutions to keep operators clear of the arc flash zone during circuit breaker racking.
Allis-Chalmers D and F gear
Closed door racking
In order to improve operator safety, Siemens offers a cost effective field modification to convert type D and F switchgear to a closed-door, remote rack design. This modification provides a cost effective solution to keep operators clear of the arc flash zone during breaker racking.
Allis-Chalmers and later Siemens manufactured type D and F medium-voltage switchgear from 1958 through the late 1980s. This gear utilized air-magnetic circuit breakers that were typically manually racked via a lever while the cubicle panel door was open.
Original floor-mounted lever racking, commonly used on type D and F switchgear, required the operator to stand in front of the circuit breaker with the panel door open.
The field modification consists of a floor-mounted screw racking device and breaker-mounted bracket to interface with the floor-mounted screw device. These additions allow end-users to either have closed-door manual racking or closed-door remote racking.
Following the field modification, the circuit breaker can be racked in and out while the operator stands outside of the arc flash zone.
The closed-door remote racking option requires the above mentioned cell and circuit breaker additions, as well as a minor front panel modification to accept a torque-regulated motor. The motor can be moved from one position to the next, thus only one motor device is required.
Remote racking modification for Siemens 5-38 kV GM Switchgear
In order to improve operator safety, Siemens offers a field modification to convert 5-38kV type GM switchgear to a remote rack design. This modification provides a cost effective solution to keep operators clear of the arc flash zone during circuit breaker racking. Siemens began manufacturing GM medium-voltage switchgear in the late 1980s and still manufactures this equipment today. This gear utilizes vacuum circuit breakers that are manually racked via a hand crank while standing in front of the cubicle. The remote racking option requires a minor front panel modification to accept a torque-regulated motor. The motor can be moved from one cell position to the next, thus only one motor device is required.
Original hand crank racking, commonly used on GM switchgear, requires the operator to stand in front of the circuit breaker with the panel door open.
Following the field modification, the circuit breaker can be racked in and out while the operator stands outside the arc flash zone.
Siemens integrated electric-racking system (SIERS) for GMSG
Features and benefits
Siemens integrated electric-racking system (SIERS) provides additional personnel protection against arc-flash exposure for operators by providing a means of remotely racking the type GMSG drawout circuit breaker. SIERS reduces the need for personal protective equipment (P.P.E.) per the NFPA-70E® standard.
- Maintain all of the safety interlocks as required by IEEE standard C37.20.2
- Logic control module for control and circuit protection
- Interference detection
- Control pendant (hand-held controller)
- High-torque, fixed-mounted dc motor
- Available for 125 V dc external power supply
- Factory installed and tested as a complete racking system.
- Powered from 120 V ac sources in switchgear
- Provision for external power source
- Integrated into the switchgear secondary control circuits or with the protection relay to provide interface with local HMI or SCADA systems
- Field retrofit for existing Siemens non-arc-resistant, medium-voltage switchgear.
Type SIERS device is available in three configurations:
- Basic version
- Local HMI version (Sm@rtGear™ power distribution solution)
- Custom version (i.e., SCADA or other system).
Siemens patented MOC-Saver system addresses the various operational issues associated with replacing air-magnetic circuit breakers. The MOC-Saver system controls the velocity operating the original cubicle MOC system, thus mitigating the increased forces that would be applied to the cubicle MOC system.
The MOC-Saver provides positive MOC switch actuation in the Open and Close directions. The MOC-Saver includes a bi-directional stored energy mechanism (snubber) and a bi-directional hydraulic velocity controller. Operation of the legacy MOC switches requires sufficient energy from the vacuum circuit breaker stored energy mechanism to reliability close the circuit breaker while not damaging the MOC system yet maintaining full interchangeability.
The 52STA actuator originally supplied with the legacy GE Magna-Blast switchgear was designed to absorb the output forces generated by the legacy circuit breakers stored energy mechanism and protect the MOC switches. Unfortunately, after years of use, the original 52STA actuator may develop a tendency to bind and not reset the MOC force that is generated in the stored energy mechanism of modern circuit breakers can be a problem for equipment owners. Fortunately, Siemens has developed replacement 52STA actuator mechanisms to prevent potential problems associated with these known issues and incorporated it in their replacement circuit breakers for legacy GE Magne-Blast switchgear in the US market.
TechTopics is a series of papers that discuss issues of interest to users or specifiers of electrical equipment. Whether your equipment was made by Allis-Chalmers, Westinghouse, GE, Federal Pacific, ITE, McGraw Edison, or another manufacturer, we will assist you to evaluate the Siemens medium-voltage vacuum replacement option which best meets your needs.
- Entire TechTopics catalog
- No. 01 - Surge limiter application recommendations for metal-clad switchgear up to 15 kV
- No. 02 - Loss of vacuum
- No. 03 - Vacuum vs. SF6
- No. 04 - kA rated circuit breakers and switchgear
- No. 05 - Reclosing applications - minimum reclosing time
- No. 07 - Current transformers - Use of 600 V CTs in metal-clad switchgear
- No. 14 - X-radiation emissions by vacuum interrupters
- No. 15 - Expected life of electrical equipment
- No. 16 - Bus joint fundamentals
- No. 17 - Main bus continuous current rating
- No. 18 - Bus joint and primary disconnect plating
- No. 19 - Bus joint current density
- No. 21 - “Bus bracing” in metal-clad switchgear
- No. 24 - Checking integrity of vacuum interrupters
- No. 25 - Shunt reactor switching applications
- No. 26 - Ground bus ratings
- No. 27 - Standards for medium-voltage metal-clad switchgear
- No. 29 - Derating factors for reclosing service
- No. 30 - Altitude correction factors
- No. 31 - Solar radiation correction factors
- No. 32 - Capacitor switching applications
- No. 33 - Clearance requirements in switchgear and control equipment
- No. 35 - Transient recovery voltage
- No. 36 - Early “b” contacts
- No. 37 - Low current switching capabilities
- No. 38 - Harmonic filter application
- No. 41 - Circuit breakers or switches - application considerations
- No. 42 - Circuit breakers or vacuum contactors - application considerations
- No. 43 - Interposing relay requirements
- No. 44 - Anatomy of a short circuit
- No. 47 - 7.2 kV equipment basic insulation levels (BIL)
- No. 48 - Fan-cooling control circuit for forced-air cooled circuit breakers
- No. 50 - Ground sensor current transformer cable routing
- No. 52 - Insulation of switchgear terminations
- No. 55 - Capacitor trip devices
- No. 56 - Switchgear outdoor enclosure type - Why isn’t it NEMA 3?
- No. 57 - Arc flash hazard labels
- No. 59 - Control power sources for switchgear
- No. 60 - Use of cable for connections in medium-voltage switchgear
- No. 61 - Circuit breaker “standard duty cycle”
- No. 62 - A bit of history on circuit breaker standards
- No. 65 - Arc-furnace switching applications
- No. 66 - Clearances
- No. 67 - %dc component
- No. 69 - Fast bus transfer times for type GMSG circuit breakers
- No. 71 - Generator circuit breakers
- No. 72 - Generator circuit breaker applications - delayed current zeroes
- No. 73 - Generator circuit breaker applications - transient recovery voltage
- No. 74 - Heat generation estimation for type GM-SG or GM-SGAR switchgear (up to 15 kV)
- No. 75 - Ferroresonance in ungrounded systems with voltage transformers connected line-to-ground
- No. 77 - Residual voltage on load side of an open circuit breaker
- No. 78 - Personal protective equipment (PPE) required with metal-clad switchgear
- No. 79 - Working space required around electrical equipment
- No. 81 - Arc-flash incident energy mitigation
- No. 82 - Continuous current capability in ambient temperatures other than 40 °C
- No. 84 - Space heater - sizing and application principles
- No. 85 - Temperature limitations for user’s power cables
- No. 86 - Use of unshielded cables for connections in medium-voltage switchgear and motor controllers
- No. 87 - Ground and test devices
- No. 88 - Application of maintenance grounds in switchgear
- No. 90 - Temperature ratings for external cables
- No. 91 - Current transformer relaying accuracies - IEEE compared to IEC
- No. 93 - Capacitor switching performance classes
- No. 94 - Circuit breaker interlocking and operating requirements
- No. 95 - Tie circuit breakers and out-of-phase applications
- No. 96 - Phase sequence versus phase arrangement
- No. 98 - Ground protection in metal-clad switchgear - ground sensor current transformers vs. residual connection of current transformers
- No. 100 - Third-party listing - UL, C-UL and CSA
- No. 102 - Tapered bus
- No. 107 - Dummy circuit breaker applications
- No. 110 - Corrosion prevention effects on electrical equipment life
- No. 113 - Preferred locations for current transformers
- No. 115 - Third-party listing/labeling and recognition
- No. 117 - MOC / TOC switches
- No. 118 - Bolted construction vs. welded construction
- No. 119 - Momentary ratings – peak or rms?
- No. 120 - High-potential testing – current doesn’t matter!
- No. 122 - Current transformer thermal-rating factor
- No. 126 - Testing of vacuum interrupters with dc test sets
- No. 129 - Interrupting capacity for system X/R ratios exceeding 17
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