The Hubbell 25kV Loadbreak Kit is an essential components in underground electrical distribution, but specifically designed for systems operating in the 25,000-volt class.
Key Features:
Applications:
Accessories Included:
Purpose and Function:
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Key Features:
- Voltage Rating: 25 kV class (sometimes referred to as 25/28 kV class). This means they are designed for systems with a nominal operating voltage up to 25,000 volts (e.g., maximum continuous line-to-ground voltage around 15.2 kV, and line-to-line up to 26.3 kV).
- Current Rating: 200 Amperes continuous. They also have short-time and fault-close ratings (e.g., 10,000 Amperes symmetrical for 0.17 seconds).
- Material: Typically made from high-quality, peroxide-cured EPDM rubber for its excellent dielectric strength, flexibility, weather resistance, and long-term performance.
- Interface Standards: Hubbell’s 25kV loadbreak bushing inserts are designed to meet or exceed IEEE Standard 386 (Standard for Separable Insulated Connectors Systems). This ensures dimensional and electrical interchangeability with 25kV loadbreak elbow connectors from other manufacturers that also comply with this standard. They also often meet IEEE Std 592 for exposed semiconducting shields.
Applications:
Hubbell 25kV Loadbreak Bushing Inserts are widely deployed in:
- Underground Distribution Systems: Primarily for connecting underground cables to transformers and switchgear in utility and industrial applications operating at 25kV.
- Substations: Providing flexible connection points within substations where underground cables are utilized.
- Renewable Energy Projects: Used in solar and wind farms to connect medium-voltage collector circuits to transformers or switchgear.
- Large Commercial and Industrial Facilities: Where higher voltage underground distribution is necessary for power delivery.
Accessories Included:
- 3 Insulated Parking Bushing
- 3 Loadbreak 225BI
- Elastimold Rod 370TR 15-35kV
- 3 Screws
- Silicone Lubricant
Purpose and Function:
- Loadbreak Capability: These inserts enable linemen to safely switch (make and break) 200 Amperes of current while the system is energized, using a hotstick. This is a crucial operational feature for isolating sections of the electrical grid or reconfiguring circuits without causing widespread outages.
- Interface with Bushing Well: A 25kV loadbreak bushing insert is designed to thread into a corresponding 200A universal bushing well, which is typically factory-installed on transformers, switches, or other medium-voltage apparatus.
- Mating with Loadbreak Elbow: It forms a complete, fully insulated, and shielded connection when a compatible 200A 25kV loadbreak elbow connector (attached to an underground cable) is plugged into it. The internal “finger contacts” of the insert engage with the probe of the elbow.
- Field Serviceability: The two-piece design (bushing well + insert) allows for easy replacement of the insert in the field if it’s damaged, which is more cost-effective and less disruptive than replacing an integral bushing
- Fully Shielded and Submersible: Constructed from high-quality EPDM rubber, these inserts are “dead-front,” meaning there are no exposed live parts when properly installed. They are also designed to be fully submersible, making them suitable for underground and vault installations where moisture is present
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