SIEMENS 3AH3 vacuum circuit breaker

SIEMENS 3AH3 vacuum circuit breaker

Product Overview and Core Features

Basic positioning: Siemens 3AH3 vacuum circuit breaker belongs to medium voltage equipment, with document version 2018 (HG 11.03), replacing the old version 2010. The product production and sales follow ISO 9001, ISO 14001, BS OHSAS 18001 certification management system.

Core advantages:

Maintenance free design: Under normal conditions (compliant with IEC 62271-1), there is no need for re lubrication or adjustment throughout the entire service life, and the characteristics are not affected by switching frequency or idle time. It supports up to 10000 operating cycles.

Wide voltage coverage: Suitable for the conventional medium voltage range of 7.2kV-40.5kV, meeting the needs of industrial and generator scenarios.

High load capacity: The maximum rated normal current of conventional models is 6300A, and the maximum short-circuit breaking current is 72kA; under the "phase separation" design scheme, the maximum rated normal current is 12000A, and the maximum short-circuit breaking current is 90kA.

Product Classification and Applicable Standards

1. Product classification and scenarios

Product type follows standard core applicable scenarios and key enhanced features

Conventional high-voltage circuit breakers IEC 62271-100 are used in industrial scenarios (such as oil refineries) to control small inductive/capacitive load currents to high-voltage short-circuit currents-

Generator circuit breaker (3AH3 6/7/8 series) IEC 62271-100+IEC/IEEE 62271-37-013 Generator operation, switching between generator power supply failure and system power supply failure 1. Coping with generator power supply failure: high DC component, no current zero point; 2. Coping with system power supply failures: higher TRV rise rate; 3. Higher testing voltage level

Split phase design circuit breaker IEC 62271-100+IEC/IEEE 62271-37-013 for large generator switchgear, single-phase isolating switch (independent enclosure) 1. Optimize parallel operation; 2. The maximum short-circuit breaking current is 90kA; 3. The maximum rated normal current is 12000A

2. General standard compliance

Basic standards: IEC 62271-100 (for circuit breakers), IEC 62271-1 (for medium voltage equipment) VDE 0671

Endurance level: All 3AH3 vacuum circuit breakers meet the E2, M2, C2, and S1 levels (IEC 62271-100)

Structure and Working Principle

1. Core structure (including component functions)

Core functions of structural components

Pole component (1) vacuum arc extinguishing chamber (6), upper/lower arc extinguishing chamber bracket (5/7), post insulator (3) 1. Vacuum arc extinguishing chamber: based on more than 40 years of mature vacuum switch technology, arc extinguishing is achieved; 2. Air insulation design, easy to clean insulation components; 3. Bear the external force and contact pressure of switch operation

Operating mechanism box (2) includes energy storage mechanism, release device, auxiliary switch, indicator, and actuator 1. It accommodates all operating mechanisms; 2. The configuration of secondary devices can be adjusted according to application scenarios to meet diverse needs

Transmission component operating rod (4), lever transmission switch action, connecting operating mechanism and pole assembly

2. Key operational mechanisms

Energy storage mechanism: The closing spring is an energy storage component that can store energy electrically or manually, and is locked after the energy storage is completed; When closing, unlock through the local "ON" button (mechanical) or remote control (electric). During the closing process, charge the opening/contact pressure spring, and automatically re store energy after discharge. It supports the OPEN-CLOSE-OPEN operation sequence.

Free release mechanism: in accordance with IEC 62271-100, if a closing command is issued and an opening command is received, the moving contact returns to the opening position and maintains it, avoiding continuous closing opening "pumping".

Closing method:

Standard configuration: Remote electric closing, local mechanical unlocking closing spring (manual mechanical closing)

Optional configuration: Manual electric closing (electrically controlled closing circuit through button, compatible with switch equipment interlocking)

3. Types and functions of release devices

Release type, power supply method, core function

Closing the soleoid DC/AC unlocks the stored energy closing spring to achieve electrical closing

External power supply (DC/AC) for shunt release, connected to voltage transformer in special circumstances. 1. Automatic disconnection through protective relay; 2. Electrical manual disconnection

When the CT operated release has no external auxiliary power supply (such as no battery), it is triggered by a protective relay (such as overcurrent time protection). When the tripping current exceeds 90% of the rated normal current, the energy storage mechanism is unlocked and the circuit is opened

When the undervoltage release circuit breaker is closed, it is permanently connected to the secondary/auxiliary voltage. When the voltage is lower than the preset value, it is unlocked and opened through the energy storage mechanism; 2. Can be connected to a voltage transformer, which automatically opens when the voltage is too low; 3. Can be paired with energy storage components to achieve delayed disconnection

Environmental conditions and technical parameters

1. Environmental conditions (compliant with IEC 60721-3-3)

Key limitations of environmental category level

The lower limit of low temperature in the 3K4 climate environment is -5 ℃, with no icing or wind blown precipitation

Biological Environment 3B1-

Mechanical environment 3M2-

Chemical active substance 3C2-

Mechanical active substance 3S2 requires cleaning of insulation components

2. Current carrying capacity and insulation strength

Current carrying capacity: The rated normal current is based on an ambient air temperature of 40 ℃ (open type switchgear), and can be increased when the temperature is below 40 ℃. The rated current levels include 1250A, 2000A, 2500A, 3150A, 4000A, 5000A, and 6300A (corresponding to characteristic curves 1-7).

Insulation strength:

Reference conditions: At an altitude of 1000m (above sea level), the rated lightning impulse withstand voltage and rated short-time power frequency withstand voltage are taken according to the "Technical Data" section.

High altitude correction: When the altitude is greater than 1000m, it needs to be adjusted according to the formula U ≥ U 0 × K a (U is the reference environmental withstand voltage, U 0 is the required withstand voltage of the installation site, K a is the altitude correction factor, which increases with altitude).

Example: When a lightning impulse withstand voltage of 75kV is required at an altitude of 2500m, the reference environment must be at least 90kV (90kV ≥ 75kV × 1.2).

3. Capacitor switch capability (endurance class C2, IEC 62271-100) Rated voltage U r (kV) Rated line charging breaking current I I (A, r.m.s.) Rated cable charging breaking current I c (A, r.m.s.) Rated single capacitor group breaking current I sb (A, r.m.s.) Rated back-to-back capacitor group breaking current I bb (A, r.m.s.) Inrush current frequency f bl (Hz)

7.2 10 10 400 400 4250

12 10 25 400 400 4250

17.5 10 31.5 400 400 4250

24 10 31.5 400 400 4250

36 10 50 400 400 4250

40.5 10 50 400 400 4250

Note: The capacity of the circuit breaker capacitor switch is 0.7 × I r of the standard specification

Selection and Configuration Guide

1. Order number structure (16 digits)

Explanation of Position Meaning

1-3 superior group/main group/sub group 1: switchgear; 2: Circuit breaker; 3 digits: Circuit breaker series

The 4-8 bit main device includes design and main device parameters (voltage, current, pole spacing, etc.)

9-16 position secondary equipment operating mechanism, release, operating voltage, auxiliary equipment, etc

Order code supplementary configuration 9/Equipment version marked with "Z" digit, supplemented with 3-digit code (a n a format), can be continuously added multiple times

Add "- Z" to the order number for special version customization requirements, followed by descriptive code; Y99 is used for unspecified special requirements and needs to be negotiated with Siemens

2. Selection of main equipment (by voltage level)

Taking some key voltage levels as examples, demonstrate the adaptation relationship between rated short-circuit breaking current and rated normal current (excerpt):

Rated voltage (kV) Rated short-circuit breaking current (kA) Rated normal current (A) - Pole distance (mm) Adaptation

7.2 50 1250(210)、2500(210/275)、4000(275/350)

7.2 63 2000(275)、3150(275)、4000(275/350)

12 50 1250(210)、2500(210/275)、4000(275/350)

12 63 2000(275)、3150(275)、4000(275/350)

36 31.5 1250(350)、2500(350)、4000(350)

36 40 3150(350)、4000(350)

Note: "n" indicates that the combination is optional

3. Selection of secondary equipment (core configuration)

Description of optional scope of configuration items

Operating mechanism electric (excluding hand crank), manual (including hand crank) Hand crank can be ordered separately as accessories

Closing method: Solenoid+manual mechanical closing, manual electric closing. Manual electric closing can be adapted to switch equipment interlocking to prevent accidental closing

Up to 3 release combinations can be used (based on 1 shunt release, additional shunt/CT operation/undervoltage release can be added). Please refer to page 19 of the document for specific combinations

Auxiliary switches 6NO+6NC, 12NO+12NC-

Plug/Terminal: 24 pole terminal block, 24 pole plug, 64 pole plug. The interface of the 64 pole plug can be connected to idle auxiliary contacts by the user

Interlock free, mechanical interlock, mechanical interlock adapted to circuit breaker handcart, withdrawal component or isolation switch

4. Additional equipment (some key options)

Additional equipment function order code

Anti condensation heating 230V AC, 50W, anti condensation Z A30

Silicon free design suitable for special environmental requirements Z A31

Low temperature adaptation (-25 ℃) can operate Z A40 in an environment of -25 ℃

3AH37 horizontal installation (≥ 5000A) 3AH37 model 5000A and above horizontal installation supplement Z A70

Gold plated auxiliary switch enhances contact reliability and adapts to different interfaces Z A17/Z A18/Z A20/Z A21

Routine test certificate with seal and report/report only/with seal signature Z F19/Z F20/Z F21

Accessories and after-sales support

1. Main accessories and spare parts (excerpt)

Attachment/Spare Part Name Specification/Remarks Order Number

Hand crank short/standard/long 3AX15 30-4A/4B/4C

Lubricant 180g Kl ü ber Isoflex Topas L32N 3AX11 33-3H

Cable bundle for 64 pole plug/24 pole plug/24 pole terminal block 3AX11 34-2D/2B/2C

Vacuum arc extinguishing chamber compatible with 3AH3117-7 model 3AY17 15-2J

Vacuum arc extinguishing chamber compatible with 3AH3228-8 model 3AY17 15-4J

Closing soleoid 24V DC 3AY15 10-5K

Undervoltage release 24V DC 3AX11 03-2B

2. Key requirements for after-sales service

Ordering spare parts: Equipment model, serial number, and manufacturing year (all on the nameplate) must be provided to ensure compatibility.

Modification requirements: When modifying the release/solenoid, the installation component order number must also be specified; Other additional equipment includes necessary installation components.

Professional operation: The vacuum arc extinguishing chamber and some spare parts need to be replaced by trained personnel..