As you deal with wiring your solar application, it’s likely that you’ll often come across PV wire and THHN wire as two frequently used types, and wonder about the differences between them. For those dabbling in solar energy, understanding these wire types is critical to getting your system up and running efficiently and smoothly.
You’ve just installed solar panels on your roof and are excited about the energy savings. Of course, you need the most appropriate wire to connect your system. It’s wise to choose photovoltaic wiring that can withstand long periods of sunlight, moisture, and temperature changes. But will THHN wire hold up well when faced with harsh environmental conditions?
In this guide, you’ll find out! We’ll dive into the details of each wire type to help you make the most informed decision for your solar equipment. Stay tuned!
An Overview of PV Wire
Photovoltaic (PV) wire is a specialized cable used to connect photovoltaic (solar) systems and is used to connect panels, inverters and batteries. The core component of a PV cable consists of a conductor, usually made of bare or tinned copper. The insulation of PV cables is usually made of cross-linked polyethylene (XLPE), a material chosen for its high resistance to environmental factors such as ozone, UV radiation and moisture. As a result, it performs well even under the harsh conditions of solar power installations. Photovoltaic wires are critical to the efficiency and safety of solar energy systems.
PV Wire Characteristics
High Voltage Ratings: PV wire is typically rated up to 600 volts for many residential and commercial solar panel installations. Standard residential solar installations can use photovoltaic wire rated at 600 volts to safely deliver the power generated by the solar panels to the inverter.
Temperature Rating: This wire can withstand high temperatures, up to +90°C in wet conditions and +150°C in dry conditions. It provides optimal performance in all climatic conditions.
Durability and reliability: XLPE insulation can withstand harsh environmental factors. It ensures longevity and robustness.
Flexibility: pv wire has better flexibility as compared to ordinary wires. It is more convenient to install in limited space.
An Overview of THHN Wire
THHN wire is a versatile general purpose wire. It represents a thermoplastic, high heat resistant nylon covered wire with stranded or solid copper conductors. The conductors are encased in heat-resistant thermoplastic insulation and further protected by a durable nylon jacket to make it suitable for a variety of environments.
THHN Wire Characteristics
Versatile Usage: Suitable for both indoor and outdoor applications, THHN wire is often used in control circuits, machine tools, and building wiring.
Enhanced Properties: The wire offers superior heat resistance, moisture resistance, and durability.
High-Temperature Performance: With its rugged construction, THHN wire can withstand temperatures up to 90°C in dry environments, ensuring reliable performance across various electrical applications.
PV Wire vs THHN Wire
Both types of wire efficiently transmit power and perform well in various environmental conditions. However, there are some key differences worth noting. It’s all about choosing the right one for your specific needs.
1. Regarding basic construction:
- Specialized photovoltaic wires have tinned copper conductors and cross-linked polyethylene (XLPE) insulation. PV cables perform well in outdoor environments where UV rays are strong.
- THHN wire is made of bare or tinned copper conductors with thermoplastic insulation and nylon coating. They offer protection in wet and abrasion resistant environments.
2. Regarding market price:
PV wires are usually more expensive than THHN wires, even close to twice as expensive, due to their special construction and solar applications. For example, for the same 10 gauge wire, the market price of THHN wire is 0.8 $ / Meter, while the price of PV wire 10 AWG is closer to 1.4 $ / Meter.
3. Regarding Intended use：
- PV cable is used to connect solar panels to the rest of the system. It can withstand sunlight, temperature fluctuations and harsh outdoor conditions.
- THHN wire is typically used for wiring in commercial and residential buildings. It has a wide range of uses such as general purpose wire for various applications such as switches, lighting and appliances.
The high temperature resistance of THHN wire makes it a popular choice for a variety of electrical applications, so can we use THHN wire in solar panel systems?
Of course we can, but we need to know the prerequisites:
UV Protection– Since standard THHN wire is not inherently UV-resistant, UV-resistant rated THHN wire must be selected for outdoor applications, or a protective conduit must be used to shield the wire from UV rays.
Electrical Code Compliance-Local, national, and international electrical codes must be followed when installing THHN wire for solar panels. This includes proper use of circuit breakers, proper grounding, and verifying that the wire size matches the current carrying capacity.
Professional Installation– If you’re unsure, it’s best to seek advice from a qualified electrician experienced in solar panel installation. Professional electricians can provide effective solutions related to best practices, basic safety precautions, and compliance with electrical codes. They can also assist with troubleshooting and provide maintenance guidance to help extend the life of your solar panel system.
Let’s wrap it up!
PV Wire is perfect for solar setups. It’s tough, handling sunlight, moisture, and temperature swings like a champ. It deals with high voltages and extreme temps for long-lasting performance. On the flip side, THHN wire is a “jack-of-all-trades”, useful for solar and other electrical tasks. It handles heat well but isn’t great for outdoor or solar-specific situations. If you’re getting into solar energy and looking for a leading solar cable manufacturer, ZW Cable has a range of products to cover your needs, helping you pick the right one for your setup.
