1. What is UF-B Wire?
UF-B wire (Underground Feeder, Type B) is a non-metallic sheathed cable designed for direct burial without the need for conduit. It's primarily used to transfer power from a main building to an outbuilding or outdoor equipment.
Compared to standard UF cable, UF-B wire features enhanced insulation and physical protection, making it ideal for long-distance underground installations and permanent outdoor wiring.
2. Structural Composition of UF-B Wire
A high-quality UF-B wire typically consists of:
Conductors: Solid copper wires for high conductivity. Common configurations include 12 2 uf wire (2 conductors + ground), 10 2 uf wire, and 6 3 uf wire (3 conductors + ground).
Insulation: Each conductor is individually insulated with color-coded PVC to prevent short circuits.
Fill Material: Prevents internal friction between wires and improves overall stability.
Outer Sheath: Durable PVC jacket offering excellent resistance to water, sunlight, and corrosion, ideal for harsh outdoor or underground environments.
3. Key Features and Advantages of UF-B Wire
Direct Burial Capability: UF-B wire is one of the few cable types approved for direct burial without the need for additional conduit, saving time and cost.
Superior Weather Resistance: Its tough outer PVC sheath protects against water ingress, UV damage, and corrosion - ensuring long-term reliability in wet soil or direct sun.
High Ratings: Most UF-B wires are rated at 90°C and 600V, making them suitable for residential and light industrial loads. For example, 10 2 uf wire is often used for powering small water heaters or air conditioning units.
4. Typical Applications of UF-B Wire
Thanks to their waterproof, UV-resistant, and direct-burial properties, UF-B wires like 12 2 uf wire, 10 2 uf wire, and 6 3 uf wire are ideal for:
Powering detached garages or workshops
Garden lighting and outdoor outlets
Agricultural pump systems
Greenhouse electrical setups
Mobile home or RV park wiring
Case Study 1: Using 12 2 UF Wire for Garden Lighting
Scenario: A homeowner wants to install low-voltage LED garden lights and an outdoor outlet for electric tools.
Solution:
12 2 uf wire is used to run power from the main panel to the backyard, buried 24 inches deep according to NEC code.
No conduit is needed. Weatherproof boxes and timers are installed for lighting control.
Result: Stable operation with minimal installation costs. The wire's waterproof sheath withstands rain and sun exposure.
Case Study 2: Using 6 3 UF Wire for a Backyard Workshop
Scenario: A 20-meter distant woodworking shop needs to power tools like saws and compressors (total ~6kW load).
Solution:
6 3 uf wire is selected for its high load capacity and support for dual-circuit distribution.
A section under a walkway is protected with PVC conduit, while the rest is directly buried.
Connected to a dedicated breaker panel for load separation.
Result: Reliable high-power delivery with no voltage drop. The thick sheath ensures long-term underground durability.
5. Installation Tips and Precautions
Burial Depth: Minimum 24 inches without conduit; 18 inches if placed in conduit.
Bending & Stripping: Use appropriate tools; the thick sheath can be difficult to manipulate.
Crossing Roads or Paths: Always use conduit for added mechanical protection.
6. UF-B Wire Specifications and Selection Guide
| Model | Conductors | Gauge | Recommended Use |
|---|---|---|---|
| 12 2 uf wire | 2 + ground | 12 AWG | Lighting, outlets, small tools |
| 10 2 uf wire | 2 + ground | 10 AWG | Water heaters, small HVAC units |
| 6 3 uf wire | 3 + ground | 6 AWG | Workshops, pumps, large outdoor circuits |
Always choose a wire size based on total load, amperage, and distance - and leave room for future expansion.
As a professional cable manufacturer with more than 30 years of production experience, Greater Wire has always maintained a leading technology in the field of UF-B underground cables. In addition to UF-B wire, Greater Wire focuses on the research and development and production of UL certified cables. Its products include more than ten mainstream UL wires such as MC Cable, THHN, XHHW, NM-B, TC-ER, etc. We have a complete UL certification system and strictly follow UL 83, UL 44 and other standards, from raw materials to factory inspection. As a professional manufacturer recognized by the international market, Dongguan Greater Wire & Cable Co., Ltd. provides stable, compliant and high-performance electrical wiring solutions for the North American, Latin American and South American markets.