High-Voltage Transformer Fuse For Transformer Overload And Short-Circuit Protection

Huixing Zhongdian (Beijing) Electric Co., Ltd. manufactures high-performance transformer fuses, which act as core overcurrent and short-circuit protection components for power systems. Our fuses cut off fault currents by melting, effectively preventing equipment damage and cascading failures in 0.6kV–35kV power distribution equipment and substation facilities.

Product Range and Applications

XRNP High-Voltage Current-Limiting Fuses for Voltage Transformers (PT)

Key Applications

• Suitable for 3.6–40.5kV, 50Hz indoor power systems.
• Installed in PT cabinets, combined PT and surge arrester cabinets, and metering cabinets.
• They provide primary protection for voltage transformers against internal short circuits and insulation breakdown.
• With a rated current up to 6.3A, they perfectly match the low-load operating characteristics of voltage transformers.
• They serve as standard protective components for distribution systems of 35kV and below.

Core Advantages

• They feature precise protection characteristics that align well with PT fault current curves.
• They deliver a 50% to 80% current-limiting effect and achieve millisecond-level fault interruption.
• Boasting high dielectric strength, they can withstand system and switching overvoltages.
• Quartz sand is used as the arc-extinguishing medium to eliminate overvoltage risks.
• The plug-in structure enables quick replacement without affecting the operation of other equipment.
• Low power consumption ensures minimal impact on PT measurement accuracy.

XRNT High-Voltage Current-Limiting Fuses for Power Transformers

Key Applications

• Suitable for 12kV/40.5kV indoor medium-voltage power systems.
• Widely applied in high-voltage switchgears, ring main units and prefabricated substations.
• They provide short-circuit and overload protection for dry-type transformers, oil-immersed transformers, power cables and overhead lines.
• Their rated current ranges from 6.3A to over 200A to fit transformers of different capacities.
• They can be used with load switches and vacuum contactors to form cost-effective protection solutions.

Core Advantages

• They offer full-range protection against overload faults (1.2–2.5 times the rated current) and short-circuit faults.
• With a rated breaking capacity of 31.5–50kA, they can handle maximum system fault currents.
• They interrupt faults before peak current occurs, reducing electromagnetic stress on transformer windings.
• Synchronous three-phase interruption prevents single-phase overvoltage issues.
• The standardized design helps reduce spare parts inventory costs.
• The sealed structure prevents moisture ingress and extends service life.

High-Voltage Current-Limiting Fuses for Oil-Immersed Transformers

Key Applications

• Applicable to 10kV/12kV/15.5kV/40.5kV power systems.
• They can be installed inside transformer tanks or on high-voltage bushings.
• They act as primary backup protection for American-style pad-mounted transformers.
• They can be matched with load switches to create integrated protection solutions.
• They are ideal for outdoor prefabricated substations operating in harsh environments.

Core Advantages

• Optimized for oil-immersed operation, they deliver excellent arc-extinguishing performance in transformer oil.
• They provide dual protection including fast short-circuit interruption and thermal overload protection.
• They operate stably under oil pressure at temperatures ranging from -25°C to +100°C.
• Oil-compatible internal materials prevent transformer insulating oil from being contaminated.
• The robust structure requires almost no routine maintenance during normal operation.
• They are a cost-effective alternative to complex high-cost protection systems.

High-Voltage Overload Protection Fuses for Oil-Immersed Transformers

Key Applications

• Suitable for 3.6–40.5kV power systems.
• Designed for environments with frequent load fluctuations, such as industrial parks, commercial complexes and renewable energy power stations.
• They function as primary or backup overload protection for oil-immersed transformers.
• They are well suited for unattended substations in urban and rural distribution networks.

Core Advantages

• Their accurate overload protection characteristics match the thermal characteristic curves of oil-immersed transformers.
• They feature graded tripping: approximately 10 minutes at 1.5 times the rated current and around 1 minute at 2 times the rated current.
• High-temperature resistant alloy fuse elements ensure reliable operation in high-temperature oil environments.
• Built-in mechanical and electrical fault indicators enable quick troubleshooting.
• Oil-friendly materials maintain good insulation and heat dissipation performance of transformers.
• They support flexible installation either inside or outside transformer tanks.

Common Advantages & Application Comparison

Universal Advantages of Transformer Fuses

• Ultra-fast response: They interrupt faults within milliseconds, much faster than circuit breakers.
• Excellent current limiting: They reduce peak fault current by 50%–80% to minimize equipment damage.
• High reliability: Their simple mechanical structure results in an extremely low failure rate.
• They form a clear isolation point to ensure safe maintenance and inspection.
• High cost efficiency: They require low initial investment and nearly no subsequent maintenance costs.
• Strong environmental adaptability: They can operate stably in high-temperature, high-humidity and dusty conditions.

Product Comparison Table

Why Choose Huixing Zhongdian Transformer Fuses

• A full-range product lineup meets all transformer protection requirements.
• All products are strictly manufactured in compliance with GB and IEC international standards.
• Comprehensive performance testing ensures stable and reliable product quality.
• Customized solutions are available for special voltage, current and environmental operating conditions.
• We offer fast delivery and one-stop, full-process technical support from design to on-site installation.
• Our products are highly compatible with transformers and switchgears from all mainstream brands.

Transformer fuses are essential and cost-efficient protective devices for power transformers and auxiliary power equipment. When used with circuit breakers and load switches, they form a multi-level power grid protection system to ensure safe and stable grid operation. As your reliable partner, Huixing Zhongdian Electric provides high-quality transformer fuses and professional protection solutions for power projects worldwide.