Request a Quote for High-Voltage Components&Equipment

Tell us your requirements — rated voltage, model, quantity, and destination — and our XBR Electric team will prepare a detailed quotation within 24 hours.
Contact Form Demo
Switchgear Insulation Components

Epoxy Contact Box Series (12kV – 40.5kV)

XBRELE’s Contact Boxes (also known as Switchgear Spouts or Static Contact Housings) are precision-molded using APG Epoxy Resin. Designed for KYN28 and UniGear panels, they ensure superior dielectric strength and PD < 5pC reliability for Medium Voltage systems.

APG Technology 12kV / 24kV / 40.5kV KYN28 Compatible IEC 60694 Standard
Product Overview

Reliable Insulation Interface for Medium Voltage Switchgear

XBRELE Contact Boxes (technically referred to as Switchgear Spouts or Static Contact Housings) serve as the critical insulation interface in air-insulated switchgear cabinets. They isolate the static contacts from the busbar compartment, ensuring safe operation for 12kV, 24kV, and 40.5kV distribution networks.

Manufactured using advanced APG (Automatic Pressure Gelation) technology with high-grade epoxy resin, our contact boxes offer superior dielectric strength and void-free mechanical stability. Unlike standard insulators, XBRELE’s epoxy contact boxes undergo rigorous testing to guarantee a Partial Discharge (PD) of < 5pC, preventing insulation breakdown over long operational cycles.

Designed for seamless compatibility, our CH3 series is the standard choice for KYN28A-12, KYN61, and UniGear ZS1 type armored removable AC metal-enclosed switchgear. Compliance with international standards, such as IEC 62271-1 High-voltage switchgear , ensures our medium voltage contact boxes meet global safety requirements for creepage distance and impulse withstand voltage (BIL).

For a complete range of insulators, bushings, and other switchgear components, please visit our main Switchgear Parts & Accessories pillar page .

Complete Contact Box Series

12kV – 40.5kV epoxy resin contact boxes. Verified specifications for KYN28, KYN61, and JYN cabinets.

12kV XBRELE 12kV Epoxy Contact Box CH3-150 for KYN28 Switchgear
CH3-12/150 Standard
  • Current 630~1250A
  • Depth 202 mm
  • Size 147×147 mm
View Specs & Drawing
12kV XBRELE Standard 12kV Contact Box CH3-180 Depth 174mm
CH3-12/180 Standard
  • Current 1250A
  • Depth 174 mm
  • Size 176×176 mm
View Specs & Drawing
12kV XBRELE Large Mouth 12kV Contact Box CH3-180 for 1250A VCB
CH3-12/180 Large
  • Current 1250A
  • Depth 205.5 mm
  • Size 176×176 mm
View Specs & Drawing
12kV XBRELE Ventilated 12kV Contact Box CH3-180 with Air Cooling Port
CH3-12/180 Vent
  • Current 1250A
  • Depth 211 mm
  • Feature Forced Air
View Specs & Drawing
12kV XBRELE High Current 1600A Contact Box CH3-190 Heavy Duty
CH3-12/190
  • Current 1600A
  • Depth 190 mm
  • Dia 145 mm
View Specs & Drawing
12kV XBRELE 2000A Heavy Duty Contact Box CH3-208 for Main Busbar
CH3-12/208
  • Current 1600~2000A
  • Depth 208 mm
  • Size 208×208 mm
View Specs & Drawing
12kV XBRELE 3150A Ultra High Current Contact Box CH3-250
CH3-12/250
  • Current 2500~3150A
  • Depth 244 mm
  • Size 250×250 mm
View Specs & Drawing
12kV XBRELE Forced Air Cooling Contact Box CH3-250 for 3150A
CH3-12/250 Vent
  • Current 2500~3150A
  • Depth 245.5 mm
  • Feature Air Cooling
View Specs & Drawing
12kV XBRELE 4000A Extreme Capacity Square Contact Box CH3-270
CH3-12/270
  • Current 4000A
  • Depth 270 mm
  • Size 270×270 mm
View Specs & Drawing
12kV XBRELE Retrofit Contact Box JYN2-12kV for Old Style Cabinet
JYN2-12 Classic
  • Current 630~1250A
  • Depth 165 mm
  • App JYN Cabinet
View Specs & Drawing
24kV XBRELE 24kV Double Insulation Contact Box CH3-225
CH3-24/225
  • Current 630~1600A
  • Depth 291 mm
  • Size 225×225 mm
View Specs & Drawing
24kV XBRELE 24kV Heavy Duty Contact Box CH3-250
CH3-24/250
  • Current 2000~4000A
  • Depth 296 mm
  • Size 250×250 mm
View Specs & Drawing
40.5kV XBRELE Improved 2-Way 40.5kV Contact Box for KYN61
CH3-40.5 2-Way
  • Current Standard
  • Depth 660 mm
  • App KYN61
View Specs & Drawing
40.5kV XBRELE Shielded 3-Way 40.5kV Contact Box with Screen
CH3-40.5 3-Way
  • Current Standard
  • Depth 660 mm
  • Type Shielded
View Specs & Drawing
40.5kV XBRELE ABB Compatible 40.5kV Contact Box Flat Structure
CH3-40.5 ABB
  • Current 2500~4000A
  • Structure Flat
  • Type ABB Type
View Specs & Drawing
40.5kV XBRELE Slanted Mouth 40.5kV Contact Box for Special Busbar
CH3-40.5 Slanted
  • Type Oblique
  • Depth 583 mm
  • App Special Busbar
View Specs & Drawing
×
Technical Diagram
Epoxy Resin Contact Box Series
Rated Voltage—
Rated Current—
Lightning Impulse (BIL)75 kV (12kV) / 125 kV (24kV)
PF Withstand42 kV (12kV) / 65 kV (24kV)
Partial Discharge< 5 pC
Depth (L)—
Mounting Size (W×H)—
Application Feature—
MaterialEpoxy Resin (APG)
StandardIEC 60694 / GB 3906
Download Drawing
Engineered for Zero-Defect Insulation

Core Technologies of XBRELE Epoxy Contact Box Series

XBRELE contact boxes (switchgear spouts) are manufactured using advanced APG (Automatic Pressure Gelation) technology, ensuring superior dielectric strength and void-free insulation structure. Our products meet rigorous international standards for Partial Discharge and Impulse Withstand Voltage, providing reliable isolation for 12-40.5kV switchgear. For more insulation components, visit our Switchgear Parts pillar page .

Insulation Quality

Low Partial Discharge (PD < 5pC)

Internal defects in epoxy insulation can lead to catastrophic failure. XBRELE contact boxes undergo strict PD testing to guarantee long-term reliability.

  • Void-Free APG Casting: Advanced molding eliminates air pockets, ensuring a dense, homogeneous epoxy structure.
  • Strict PD Limits: Every unit is tested to ensure Partial Discharge is less than 5pC at rated voltage.
  • Extended Service Life: Low PD levels prevent insulation degradation, significantly extending the lifespan of your switchgear components.
Safety & Protection

High Impulse Withstand Voltage (BIL)

Designed to protect against lightning surges and switching transients, our epoxy contact boxes offer exceptional insulation margins.

  • IEC 60694 Compliant: Meets or exceeds standard BIL requirements: 75kV (12kV), 125kV (24kV), and 185kV (40.5kV).
  • High Creepage Distance: Optimized surface geometry ensures safe operation even in high-humidity or polluted environments.
  • Reference Standard: Performance verified against IEEE/IEC standards for high-voltage switchgear insulation.
Quality Assurance

X-Ray Flaw Detection for Structural Integrity

Hidden cracks or poor bonding between copper inserts and epoxy can compromise safety. We use X-Ray technology to see what others can’t.

  • Non-Destructive Testing (NDT): 100% X-Ray inspection detects internal fissures, bubbles, or insert misalignments.
  • Precise Insert Bonding: Ensures robust mechanical connection between the static contact housing and the busbar system.
  • Visual Verification: Guarantees that every contact spout leaving our factory is structurally sound and ready for installation.
Quality Control

Manufacturing & Testing of Epoxy Contact Box Series

XBRELE combines advanced APG (Automatic Pressure Gelation) casting, precision mold design, and rigorous 100% routine testing to ensure that our contact boxes (switchgear spouts) deliver zero-defect insulation performance for 12-40.5kV medium voltage switchgear.

APG Casting & Assembly Process

Our manufacturing line for epoxy resin components is optimized to eliminate internal voids, ensure high mechanical strength, and achieve precise dimensional tolerance for seamless KYN28/UniGear integration.

  • 01

    Mold Preparation & Pre-heating

    Molds are cleaned and pre-heated to precise temperatures. Copper inserts (static contact housings) are positioned with high accuracy to ensure alignment.

  • 02

    APG Vacuum Casting

    Epoxy resin is injected under vacuum and high pressure using APG technology. This eliminates air bubbles, ensuring high dielectric strength and < 5pC partial discharge.

  • 03

    Curing & Demolding

    Controlled curing cycles prevent internal stress and micro-cracking. Once cured, the contact box is demolded and inspected for surface finish.

  • 04

    X-Ray Flaw Detection

    Every batch undergoes X-Ray inspection to verify the bonding between the copper insert and the epoxy matrix, ensuring no hidden structural defects.

  • 05

    Final Testing & Packing

    Routine tests for dimension, withstand voltage, and visual appearance are conducted before the switchgear components are packed for shipment.

QA Standards

Routine & Type Tests

All contact boxes are tested in accordance with IEC 60694 / GB 3906 standards to guarantee safety and reliability in critical power distribution networks.

Dielectric Performance

  • Power Frequency Withstand Voltage: 42kV (1min) for 12kV units; 65kV for 24kV; 95kV for 40.5kV.
  • Partial Discharge (PD) Test: Guaranteed < 5pC at 1.1x rated voltage to prevent insulation aging.
  • Impulse Voltage (BIL): Verified to withstand lightning impulses up to 75kV-185kV (Peak).

Mechanical & Physical Properties

  • Cantilever Load Test: Verifies the mechanical strength of the terminal to withstand busbar stress.
  • Glass Transition Temperature (Tg): Ensures material stability under high operating temperatures.
  • Test procedures reference guidance from IEEE/IEC standards for solid electrical insulation.

Dimensional Verification

  • Precision check of mounting hole centers and aperture diameters.
  • Verification of insert thread quality and depth.
  • Surface creepage distance measurement.
For detailed test reports or to view other insulation products like bushings and insulators, please visit our Switchgear Parts pillar page .
Delivery & Project Support

Global Supply Chain for Switchgear Components

XBRELE ensures rapid delivery of 12kV-40.5kV epoxy contact boxes and switchgear spouts to panel builders worldwide. We coordinate mold customization, secure packaging, and technical support for both OEM production and retrofit maintenance projects.

Fast Replacement

Stock Availability for Standard Models

We maintain a strategic inventory of high-demand models like CH3-12/150 and CH3-12/250 to support urgent maintenance needs for KYN28/UniGear panels.

  • In-Stock Items: Ship within 3-5 days for standard 12kV contact boxes.
  • Bulk OEM Orders: 15-20 days production lead time for large batches.
  • Retrofit Kits: JYN2-12 and older static contact housing replacements available.
  • Sample Policy: Express delivery for prototype verification.
OEM Customization

Mold Design for Special Busbar Systems

Beyond standard catalogs, XBRELE offers mold customization services to fit unique busbar geometries or specific medium voltage switchgear designs.

  • Dimensional Adaptation: Custom mounting hole spacing and aperture diameters.
  • Special Shapes: Slanted mouth, ABB-compatible flat structures, or shielded types.
  • Insert Material: Copper or brass insert options based on conductivity requirements.
  • Private Labeling: Custom laser marking for OEM brand partners.
Export Packaging

Secure Transport for Epoxy Components

Epoxy resin requires careful handling to prevent surface chipping. We use reinforced packaging to ensure every contact spout arrives in perfect condition.

  • Individual Boxing: Each contact box is wrapped in foam and boxed separately.
  • Palletization: Heavy-duty wooden pallets with shrink wrap for sea/air freight.
  • Impact Protection: Corner guards and internal cushioning to absorb transport shock.
  • Documentation: Full test reports and COC included with every shipment.
Explore All Switchgear Parts
FAQ · Epoxy Contact Box

Common Questions About Switchgear Contact Boxes

Technical answers regarding contact box selection, material properties, partial discharge limits, and compatibility with KYN28 and other medium voltage switchgear cabinets.

What is the function of a contact box in MV switchgear? +
A contact box (also known as a switchgear spout or static contact housing) acts as an insulation barrier and support structure. It isolates the high-voltage static contacts from the grounded metal compartment, ensuring safe connection with the vacuum circuit breaker handcart in 12kV-40.5kV air-insulated switchgear.
Why use Epoxy Resin (APG) instead of other materials? +
Epoxy resin molded via the APG (Automatic Pressure Gelation) process offers superior dielectric strength, mechanical toughness, and moisture resistance compared to porcelain or DMC. The void-free casting ensures low partial discharge (< 5pC), which is critical for the long-term reliability of medium voltage distribution equipment.
How do I choose the right contact box for KYN28 switchgear? +
Selection depends on three factors: Rated Voltage (12kV vs 24kV), Rated Current (630A-1250A use standard CH3-150/180; 1600A+ use CH3-250/270), and the Pole Distance (150mm, 210mm, or 275mm) of your cabinet. XBRELE offers standard models compatible with most KYN28A-12 and UniGear ZS1 panels.
What causes partial discharge in contact boxes? +
Partial discharge is often caused by internal air voids in the insulation or poor bonding between the copper insert and the epoxy. This can lead to eventual insulation breakdown. XBRELE prevents this by using X-Ray inspection and strict APG process controls, guaranteeing a PD level well below IEC standards.
Which standards do your contact boxes comply with? +
Our products are designed and tested in accordance with IEC 60694 (Common specifications for high-voltage switchgear) and GB 3906. This includes type tests for Lightning Impulse Withstand Voltage (BIL) and Power Frequency Withstand Voltage. For more details, refer to IEC 62271-1 standards.
Do you offer contact boxes for 40.5kV systems? +
Yes, we manufacture heavy-duty 40.5kV contact boxes (CH3-40.5 series) for KYN61 switchgear. These include 2-way and 3-way shielded designs suitable for high-voltage applications up to 2500A. View our full range on the Switchgear Parts pillar page .