RVV Sheathed Wire (Flexible Cable)
Characteristics:
Structure: RVV wire (Reinforced Vinyl insulated and sheathed flexible cable) consists of two or more insulated flexible copper wires enclosed in a PVC sheath.
Flexibility: It is designed to be flexible, making it easy to install in complex environments where the wire needs to bend or move.
Sheath: The outer PVC sheath provides protection against mechanical damage, moisture, and some chemicals.
Voltage Rating: Typically, RVV cables are rated for 300/500V, but this can vary depending on the specific type and application.
Applications: Commonly used in indoor environments, for connecting electrical appliances, control circuits, and communication equipment. It's suitable for situations where flexibility is a priority, like in movable equipment or installations with frequent adjustments.
Advantages:
Ease of Installation: The flexibility of RVV wire makes it easy to install, particularly in tight spaces or where wiring needs to navigate around obstacles.
Versatility: It can be used in a wide range of low-voltage applications, making it a versatile choice for various electrical installations.
Safety: The PVC sheath provides good insulation and protection, making it safe for indoor use where mechanical stress is minimal.

THHN Wire (Thermoplastic High Heat-Resistant Nylon-Coated Wire)
Characteristics:
Structure: THHN wire is made of a single conductor, typically copper, insulated with a thermoplastic material and coated with a nylon jacket.
Heat Resistance: The wire is rated for higher temperatures, typically up to 90°C in dry conditions and 75°C in wet conditions.
Nylon Coating: The nylon coating provides additional protection against abrasion, chemicals, and oil.
Voltage Rating: THHN wire is usually rated for up to 600V.
Applications: Commonly used in building wiring, including for electrical circuits in homes, commercial buildings, and industrial facilities. It is often used in conduit or other protective enclosures.
Advantages:
Durability: The thermoplastic insulation and nylon coating provide excellent protection against physical damage and environmental factors, making THHN wire durable in a wide range of conditions.
Heat Resistance: It can operate at higher temperatures, making it suitable for environments where heat exposure is a concern.
Versatility: THHN wire can be used in both dry and wet locations, adding to its versatility in various building and industrial applications.

Key Differences:
Flexibility:
RVV: Highly flexible, ideal for movable or adjustable installations.
THHN: Less flexible compared to RVV, but still manageable for most installations, particularly in conduit.
Temperature and Environmental Resistance:
RVV: Suitable for low to moderate temperature environments; typically used indoors.
THHN: Designed to withstand higher temperatures and is suitable for both dry and wet conditions, often used in harsher environments.
Construction:
RVV: Multi-conductor, with a focus on flexibility and ease of use.
THHN: Single conductor, with a focus on durability and resistance to heat and chemicals.
Applications:
RVV: Ideal for indoor use in low-voltage, flexible applications like appliances and communication equipment.
THHN: Preferred for building wiring, particularly in environments where higher temperatures, moisture, or exposure to chemicals might be a concern.

RVV Wire: Best for flexible, low-voltage applications where ease of installation is crucial.
THHN Wire: Best for more demanding environments that require higher temperature resistance and durability, such as building wiring in commercial or industrial settings.