Indoor Box-Type Fixed Metal-Enclosed Switchgear
The Indoor Box-Type Fixed Metal-Enclosed Switchgear is a high-performance medium-voltage electrical distribution and protection system specifically engineered for industrial facilities, utility substations, commercial infrastructure, renewable energy projects, and intelligent power distribution networks. The switchgear adopts a fully enclosed metal-clad structure integrating vacuum circuit breakers, disconnect switches, protection relays, current transformers, voltage transformers, and intelligent control systems within a compact fixed cabinet configuration. This design provides reliable medium-voltage power distribution while significantly improving operational safety and equipment stability. Designed according to international medium-voltage distribution standards, the indoor box-type switchgear delivers outstanding insulation performance, mechanical durability, and thermal stability under continuous operating conditions. The compartmentalized cabinet structure effectively separates busbar chambers, breaker compartments, cable chambers, and low-voltage control sections to reduce electrical fault propagation risks and simplify maintenance procedures. The fixed structure design improves installation stability and ensures dependable long-term operational performance for mission-critical electrical systems. The Indoor Box-Type Fixed Metal-Enclosed Switchgear supports intelligent monitoring systems, digital protection devices, remote communication interfaces, and smart-grid automation technologies for modern electrical distribution environments. With flexible configuration capabilities and scalable electrical protection architectures, the switchgear provides stable medium-voltage switching, fault isolation, and electrical control performance for industrial automation systems, utility networks, transportation infrastructure, and commercial power systems.
- Primary Voltage Ratings 3.6kV / 7.2kV / 12kV / 24kV / 40.5kV
- Type Switchgear
- Standards IEC 62271 / ANSI / IEEE / GB
- Application utility substations, industrial manufacturing facilities
- Certificate UL, CESI, IEEE
- Cooling Method ONAN / ONAF
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
Indoor Box-Type Fixed Metal-Enclosed Switchgear
Indoor Box-Type Fixed Metal-Enclosed Switchgear Data Sheet
| Parameter Category | Technical Parameter | Specification Range / Typical Value | Unit | Remarks / Standard |
| Rated Voltage | Ur | 12 / 24 | kV | IEC 62271-1 |
| Rated Current | Ir | 630 / 1250 / 1600 / 2000 / 2500 | A | Main busbar |
| Rated Short-time Withstand Current | Ik | 20 / 25 / 31.5 / 40 | kA | 4s duration |
| Peak Withstand Current | Ip | 50 / 63 / 80 / 100 | kA | Peak value |
| Rated Short-Circuit Breaking Current | Isc | 20 / 25 / 31.5 / 40 | kA | Fixed vacuum breaker |
| Power Frequency Withstand Voltage | Ud | 42 / 65 | kV | 1 minute |
| Lightning Impulse Withstand Voltage | Up | 75 / 125 / 145 | kV | 1.2/50μs |
| Insulation Medium | - | Vacuum / Air Composite | - | Fixed installation |
| Protection Degree | IP Code | IP4X (standard) / IP41 | - | Box-type enclosure |
| Operating Mechanism | - | Spring Energy / Manual / Electric | - | Fixed type |
| Mechanical Endurance | M | 8,000 – 15,000 | Operations | Circuit breaker |
| Internal Arc Classification | IAC | AFL 25kA / 1s | - | Safety feature |
| Busbar Material | - | Copper with tin plating | - | High conductivity |
| Ambient Temperature | - | -25°C to +40°C | °C | Indoor operation |
| Installation Type | - | Indoor floor standing, fixed | - | Box-type design |
| Smart Monitoring | - | Optional IEC 61850 & temperature monitoring | - | Expandable |
Customization Optional
Indoor Box-Type Fixed Metal-Enclosed Switchgear
Our indoor box-type fixed metal-enclosed switchgear provides flexible customization to accommodate specific project needs and site limitations. Customers can choose from various voltage and current ratings, different incoming and outgoing feeder configurations, and multiple busbar arrangement options. The box-type enclosure dimensions, door layouts, and cable entry directions (bottom or top) can be modified according to installation space. We also offer choices in protection relay brands, instrument transformer specifications, and earthing switch types to perfectly align with system requirements.
In addition, we support enhanced safety and intelligent features such as arc fault detection systems, digital metering devices, and remote control interfaces. For special environments, anti-condensation heaters, dust-proof filters, and upgraded enclosure coatings are available. Our engineering team works closely with clients during the design phase to ensure seamless integration with existing power infrastructure. All custom solutions are manufactured under strict quality control and fully comply with IEC 62271, GB/T 3906, and other relevant standards, delivering optimal performance, cost efficiency, and long service life.
Packing and Shipping
Indoor Box-Type Fixed Metal-Enclosed Switchgear
The Indoor Box-Type Fixed Metal-Enclosed Switchgear is packaged using industrial heavy-duty export protection methods to ensure safe transportation, secure storage, and reliable international shipment under demanding logistics conditions. Prior to packaging, the complete switchgear assembly undergoes structural inspection, enclosure sealing verification, anti-corrosion coating assessment, and electrical component protection procedures to minimize transportation risks and environmental exposure. Sensitive electrical devices including protection relays, intelligent communication modules, metering equipment, and monitoring systems are additionally protected using moisture-proof and vibration-resistant industrial packaging materials.
Each switchgear cabinet is internally reinforced using transportation locking systems and heavy-duty steel support structures to prevent movement during road, railway, or sea transportation. Vacuum circuit breakers, busbar assemblies, cable compartments, auxiliary control devices, and internal electrical structures are securely fixed to reduce vibration impact and maintain assembly integrity throughout shipment operations. External cabinet surfaces are protected using industrial waterproof wrapping film, reinforced edge guards, anti-scratch protective covers, and impact-resistant fastening systems to preserve enclosure quality during long-distance transportation and storage.
Depending on project dimensions, transportation routes, and customer logistics requirements, the indoor box-type switchgear may be shipped using skid-mounted transportation systems, steel-frame export packaging, fumigation-free wooden crates, or direct container securing structures compliant with international logistics standards. Additional anti-condensation protection systems, anti-vibration reinforcement measures, and marine-grade corrosion protection solutions are available for coastal installations, mining operations, and remote infrastructure projects requiring extended transportation durations.
Shipping documentation generally includes factory inspection certificates, packing lists, electrical schematics, wiring diagrams, operation manuals, quality inspection reports, and export compliance certifications. Customers may additionally request multilingual labels, customized shipping marks, installation guidance manuals, and project-specific logistics coordination support. The complete packing and shipping process is designed to maintain equipment reliability, reduce transportation risks, and ensure safe delivery to the final installation destination.
Each switchgear cabinet is internally reinforced using transportation locking systems and heavy-duty steel support structures to prevent movement during road, railway, or sea transportation. Vacuum circuit breakers, busbar assemblies, cable compartments, auxiliary control devices, and internal electrical structures are securely fixed to reduce vibration impact and maintain assembly integrity throughout shipment operations. External cabinet surfaces are protected using industrial waterproof wrapping film, reinforced edge guards, anti-scratch protective covers, and impact-resistant fastening systems to preserve enclosure quality during long-distance transportation and storage.
Depending on project dimensions, transportation routes, and customer logistics requirements, the indoor box-type switchgear may be shipped using skid-mounted transportation systems, steel-frame export packaging, fumigation-free wooden crates, or direct container securing structures compliant with international logistics standards. Additional anti-condensation protection systems, anti-vibration reinforcement measures, and marine-grade corrosion protection solutions are available for coastal installations, mining operations, and remote infrastructure projects requiring extended transportation durations.
Shipping documentation generally includes factory inspection certificates, packing lists, electrical schematics, wiring diagrams, operation manuals, quality inspection reports, and export compliance certifications. Customers may additionally request multilingual labels, customized shipping marks, installation guidance manuals, and project-specific logistics coordination support. The complete packing and shipping process is designed to maintain equipment reliability, reduce transportation risks, and ensure safe delivery to the final installation destination.
32
32 years of industry experience
Manufacturer Test
Indoor Box-Type Fixed Metal-Enclosed Switchgear
Progress Test
The Indoor Box-Type Fixed Metal-Enclosed Switchgear undergoes a comprehensive multi-stage production testing program designed to maintain strict quality control and electrical safety throughout the manufacturing process. The testing procedure begins with enclosure structural verification, dimensional tolerance analysis, busbar installation inspection, and coating thickness measurement to ensure mechanical durability and environmental protection performance under industrial operating conditions. Electrical verification procedures include dielectric testing, relay protection logic inspection, secondary circuit simulation, breaker synchronization testing, and communication protocol verification. Functional simulations are performed to evaluate switchgear response under overload, short-circuit, earth fault, and emergency shutdown conditions. Intelligent monitoring systems, automatic control functions, and SCADA communication interfaces are additionally tested to ensure operational stability and accurate signal transmission.
Design Tests
All transformers will be tested after finishing the production, test items as follows:
♦ Insulation Power Factor
♦ Ratio, Polarity, and Phase Relation
♦ Winding Resistance
♦ Impulse Tests
♦ On load Loss Test
♦ No Load Loss Test
♦ Transformer Turns Ratio/TTR (All Tap Voltages)
♦ Impedance Voltage & Load Loss (Rated Voltage)
♦ Polarity, 1-Ph / Phase Relation, 3-Ph (Rated Voltage)
♦ Excitation & No-Load Loss (Rated Voltage)
♦ Applied Voltage
♦ Induced Voltage
♦ Lightning Impulse
♦ Insulation Resistance (Rated Voltage)
♦ Temperature Rise
♦ Dielectric Withstand (Hipot)
Factory Acceptance Test
The transformer Factory Acceptance Test program for transformer-integrated Indoor Box-Type Fixed Metal-Enclosed Switchgear systems is designed to guarantee manufacturing quality consistency and dependable field operation in industrial and utility power distribution applications. The testing procedure begins with visual inspections and dimensional verification of transformer tanks, bushings, grounding terminals, cooling systems, enclosure coating quality, and accessory installation to confirm conformity with approved engineering drawings. The transformer insulation system is evaluated using insulation resistance testing, polarization index analysis, dielectric withstand testing, and induced overvoltage testing to verify insulation stability under electrical stress conditions. Additional electrical performance tests include transformer ratio measurement, impedance voltage testing, polarity confirmation, load loss analysis, and winding resistance measurement to ensure efficient transformer performance and accurate voltage regulation.
Routine Test - Circuit Breaker Timing & Motion Analysis
Purpose of Testing
Evaluate the integrity of the main circuit insulation and contact connections. Identify potential defects such as moisture ingress, aging, or contamination in the insulation system, and verify that contact resistance is within acceptable limits to prevent overheating.
Testing Equipment
For Insulation Resistance: Megohmmeter (typically 2500V or 5000V DC).For Circuit Resistance: Micro-ohmmeter (DC resistance tester) or Precision DC current source.Auxiliary Tools: Thermometer/hygrometer (for temperature correction).
Pre-Test Preparation
Ensure the switchgear is de-energized, isolated, and properly grounded. Clean the test terminals and bushings to remove dust or moisture. For insulation tests, discharge all capacitive loads (cables, busbars) thoroughly through the grounding switch or shorting links.
Test Progress
1. Insulation Test: Connect the megger leads to the busbar phases and ground. Apply the test voltage (e.g., 2500V DC) and hold for 1 minute.2. Circuit Resistance Test: Connect the micro-ohmmeter current leads to the main busbar or circuit breaker terminals. Pass a low DC current (e.g., 100A) and record the voltage drop.
Temperature Correction
Correct the measured insulation resistance to a standard reference temperature (typically 20°C) using the appropriate exponential formula to ensure compliance with standards across different ambient conditions.
Circuit Resistance Test
Connect the tester leads to the main busbar or circuit breaker terminals. Pass a low DC current (e.g., 100A or 200A as per standard) and accurately record the voltage drop across the connection point. Ensure the equipment is energized only if it complies with specific hot-line testing safety protocols, otherwise perform cold-resistance measurement after de-energization
Mechanical Characteristic Test
Purpose: To verify the operational performance and timing of the circuit breaker mechanism, ensuring compliance with speed and travel requirements for arc extinction.Procedure: Use a dedicated Circuit Breaker Mechanical Tester. Connect the tester to the control circuit (closing/opening coils) and the secondary side of the travel transducer. Perform several opening and closing operations without load. Record key parameters: Opening/Closing time, Synchronization between three phases, Travel distance, Overshoot, and Contact pressure.
Power Frequency Withstand Test (AC Hipot)
Purpose: To validate the integrity of the main insulation system under high voltage stress.Equipment: AC high voltage test set.Procedure: Energize the equipment and apply the specified power frequency test voltage (e.g., 42kV for 1 minute for 10kV switchgear) between phases/inter-phase and ground. Monitor the leakage current. The test is considered passed if the insulation does not break down and the current remains stable within the standard limit. (Note: This is a destructive test; perform only on de-energized and properly discharged equipment).
Partial Discharge (PD) Measurement
Purpose: To identify internal insulation defects such as voids, cracks, or contamination that are not detectable by insulation resistance tests.Procedure: Inject the test voltage up to 1.3~1.5 times the rated voltage. Use a PD detector connected to the coupling capacitor or directly to the test object to measure the apparent charge (pC). Ensure the background noise level is below the detection threshold. Analyze the PD patterns to locate the faulty chamber.
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
Indoor box-type fixed metal-enclosed switchgear is widely used in urban residential power distribution substations, small and medium-sized industrial factories, commercial building power centers, and school campus electrical systems. It is also suitable for warehouse and logistics park distribution networks.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
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What is a Transformer?A transformer is an electrical device used to change the voltage of alternating current (AC). It works on the principle of electromagnetic induction, converting high-voltage current into low-voltage current or low-voltage current into high-voltage current. Transformers are widely used in power transmission, distribution systems, and various electronic devices.
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What are the main uses of a transformer?The main use of a transformer is voltage conversion. Transformers are used in power transmission systems to help transfer electricity from power plants to consumers. In addition, transformers are also used in electronic devices such as chargers, televisions, power adapters, etc., to adjust the voltage to meet the requirements of different devices.
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Do you have UL listed?Yes, our transformer has UL listed. We have exported to America many pad mounted transformer,substation transformer and HV.
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