Product Overview
The Type VBF Outdoor Vacuum Circuit Breaker is an outdoor medium-voltage vacuum circuit breaker designed for high operational reliability and minimum maintenance. It is equipped with an ESH spring-operated mechanism and is suitable for outdoor installation in medium-voltage power distribution systems.
The breaker consists of three main assemblies: the pole assembly, the cabinet with operating mechanism, and the galvanized steel supporting structure. Each pole contains a vacuum interrupter, current transfer contacts, insulating pull rod, porcelain housing, and primary terminal connectors.
The operating mechanism is housed in a painted mild steel cabinet and includes a motor-charged spring mechanism, anti-condensation heater, status indicator, mechanical counter, auxiliary switches, control switches, anti-pumping relay, fuses, and terminal blocks.
The VBF breaker is designed for safe switching, fault interruption, remote or manual operation, and reliable outdoor service under harsh environmental conditions.
Product Features
Outdoor Medium-Voltage Design
Type VBF is designed specifically for outdoor medium-voltage applications. Its pole assemblies are housed in porcelain insulators and filled internally with insulating gas to support reliable outdoor operation.
Key features include:
· Outdoor live tank vacuum breaker structure
· Porcelain housing for pole insulation
· Vacuum interrupter technology
· Gas-filled pole assembly
· Galvanized steel supporting structure
· Painted mild steel operating cabinet
High Operational Reliability
The circuit breaker is equipped with a robust ESH operating mechanism using helical tension springs for both closing and opening operations.
Reliability features include:
· Simple and robust operating mechanism
· Spring-operated closing and tripping system
· Motor charging of closing spring
· Manual spring charging option
· Mechanical operation counter
· Status indication
· Anti-pumping relay
· Auxiliary switches for control and signaling
Low Maintenance Design
The VBF breaker is designed for long service life with minimized maintenance requirements.
Maintenance-related features include:
· Vacuum interrupter technology
· Spring-operated ESH mechanism
· Periodic maintenance intervals based on ambient condition
· Recommended spare parts list
· Clear troubleshooting and component replacement procedures
Safe Operation and Handling
The document provides detailed safety provisions for high-voltage equipment and stored-energy mechanisms.
Safety features and provisions include:
· Stored energy safety precautions
· Requirement to discharge closing and opening springs before work
· Earthing before maintenance
· High-voltage supply disconnection before service
· Warning categories for danger, warning, caution and important notes
· Porcelain insulator handling precautions
Flexible Installation Options
The breaker supports different installation arrangements, including standard installation and lower-height cabinet installation.
Installation options include:
· Cabinet attached to pole duct
· Cabinet installed at lower height using extended drive link and pipe assembly
· Foundation-mounted galvanized steel support structure
· High-voltage, low-voltage and earthing connections
Reliable Spring Charging System
The ESH mechanism allows both electrical and manual charging of the closing spring.
Charging features include:
· Motor-operated spring charging
· Manual charging handle
· Closing spring charged indication
· Motor cut-off switch
· Charging time less than 15 seconds
· Maximum manual charging force of 170 N
Main Functions
Medium-Voltage Circuit Switching
The VBF breaker provides switching and interruption for medium-voltage electrical circuits in outdoor applications.
Main switching functions include:
· Circuit closing
· Circuit opening
· Short-circuit interruption
· Load current switching
· Fault clearing
Vacuum Interruption
The breaker uses vacuum interrupters to interrupt current safely and efficiently.
Vacuum interruption supports:
· Fast arc extinction
· Reliable dielectric recovery
· Reduced maintenance compared with other interruption technologies
· Long operating life
Spring-Operated Closing and Opening
The ESH operating mechanism uses stored mechanical energy for breaker operation.
Functions include:
· Electrical spring charging
· Manual spring charging
· Electrical closing
· Mechanical closing
· Electrical tripping
· Mechanical tripping
· O-C-O operating capability without recharging
Remote and Local Operation
The operating cabinet includes control elements enabling both local and remote operation depending on control circuit arrangement.
Supported functions include:
· Local control through cabinet devices
· Remote open command
· Remote close command
· Auxiliary circuit connection through terminal blocks
· Status signaling through auxiliary contacts
Anti-Pumping Protection
The breaker includes an anti-pumping relay to prevent repeated closing operations when an open command is present or when the close command remains active.
This function improves safety and prevents mechanical stress.
Status Indication and Monitoring
The control cabinet provides operational feedback and status information.
Monitoring and indication functions include:
· Breaker open / closed status indication
· Spring charged / discharged indication
· Mechanical operation counter
· Auxiliary switch signaling
· Fuse and terminal block integration
Anti-Condensation Heating
The control cabinet is equipped with an anti-condensation heater to prevent moisture accumulation and support reliable operation, especially during storage or harsh outdoor conditions.
Commissioning and Testing
The instruction document defines commissioning checks before putting the breaker into service.
Commissioning tests include:
· Insulation resistance measurement
· Mechanical operation test
· Motor charging test
· Anti-pumping device test
· Heater function check
· Auxiliary circuit verification
Specifications
General Technical Data
|
Parameter |
Specification |
| Product type | Outdoor medium-voltage vacuum circuit breaker |
| Type designation | VBF 36 16 25 |
| Standard | IEC 62271-100 |
| Rated voltage | 36 kV |
| Available voltage version | Also available in 24 kV |
| Rated frequency | 50 Hz |
| Insulation level | 70 / 170 kVp |
| Rated normal current | 1250 A / 1600 A |
| Short-circuit breaking current | 26.3 kA |
| Operating sequence | O – 0.3 s – CO – 3 min – CO |
| Weight | Approximately 800 kg to 850 kg |
| Minimum ambient temperature | -30°C |
Pole Assembly
|
Component |
Description |
| Number of poles | Three separate poles |
| Mounting | Mounted on a common duct |
| Interruption unit | Vacuum interrupter / vacuum bottle |
| Current transfer | Current transfer contacts |
| Mechanical linkage | Insulating pull rod |
| Housing | Porcelain insulator body |
| Primary terminals | Terminal connectors such as NEMA 4 |
| Internal filling | SF6 or nitrogen gas |
| Filling pressure | 1.5 bar absolute |
Operating Mechanism and Cabinet
|
Item |
Specification |
| Operating mechanism type | ESH spring-operated mechanism |
| Cabinet material | Painted mild steel |
| Spring system | Helical tension springs for closing and opening |
| Spring charging | Electrical motor or manual handle |
| Motor charging time | Less than 15 seconds |
| Manual charging force | Maximum 170 N |
| Operation capability | O-C-O without recharging |
| Auxiliary switches | 13 NO + 13 NC |
| Cabinet equipment | Anti-condensation heater, status indicator, mechanical counter, control switches, anti-pumping relay, AC/DC fuses, terminal blocks |
Steel Supporting Structure
|
Item |
Specification |
| Structure material | Galvanized steel |
| Function | Supports breaker on foundation |
| Foundation bolts | M20 bolts referenced for lower legs |
| Installation method | Mounted on structure support angles |
Installation Tools
|
Tool / Equipment |
Specification |
| Erection crane | 1500 kg capacity |
| Torque wrench | 6 to 100 Nm |
| Standard spanners | 7 mm to 43 mm |
| Lifting method | Crane with slings or forklift |
Electrical Connections
|
Connection Type |
Specification |
| High-voltage connection | M12 stainless steel or galvanized bolts |
| Terminal preparation | Clean terminals with wire brush and apply conducting grease |
| Low-voltage connection | Connect auxiliary circuits according to schematic diagram |
| Cable entry | Removable gland plate |
| Earthing | Connect securely to station earthing system |
| Earthing conductor requirement | Cross-section not less than the earth connection pad |
Commissioning Requirements
|
Test / Check |
Requirement |
| MV circuit insulation resistance | 2500 V Megger, minimum 200 MΩ |
| Auxiliary circuit insulation resistance | 500 V Megger, several MΩ |
| Mechanical operation | Manual charge and operation check |
| Motor charging | Spring charging in less than 15 seconds |
| Anti-pumping test | Breaker must not re-close under open command with close command still present |
| Heater check | Space heater must be functional |
Maintenance Intervals
|
Maintenance Operation |
Normal Ambient |
Dusty / Polluted Ambient |
| General inspection | 2 years | 1 year |
| Insulation measurement | 4 years | 2 years |
| Lubrication | 2 years | 1 year |
| Mechanism maintenance | 5 years / 10,000 operations | 3 years / 5,000 operations |
| Complete overhaul | 10 years / 10,000 operations | 5 years / 10,000 operations |
ESH Mechanism Working Data
|
Function |
Description |
| Spring charging method | Electrical geared motor or manual handle |
| Closing operation | Close release rotates half-shaft and releases closing lever |
| Tripping operation | Open release actuates latch assembly and tripping spring opens the breaker |
| Motor cut-off | Plastic cam activates motor cut-off switch after full charge |
| Closing spring indication | Spring charged indication appears after manual or motor charging |
Recommended Spare Parts
|
Spare Part |
Part Number |
| Spring charging motor | 15032 |
| Tripping / closing coils | 15030 A / B |
| Micro-switches | 15033 |
| Auxiliary switches | 15027 |
| Shock absorber | 15007 |
| Operating mechanism | 15000A |
