The 120mm² and 250mm² specifications of 600V Thhn/Thwn Stranded Copper Wires have precise and detailed settings in terms of specification parameters to meet the stringent requirements of medium and large-scale power distribution scenarios.

The rated voltage of this wire is 600V, which fully complies with the standards of medium and large-scale power distribution systems. It can be perfectly compatible with various high-voltage power distribution equipment, switches, transformers, etc., ensuring the stability and safety of power during transmission and providing a solid foundation for the power supply of medium and large-scale industrial and commercial facilities.

The 120mm² wire has a conductor composed of multiple strands of fine copper wires twisted together, with a conductor diameter of approximately 12.4mm. Under the condition of 90°C in a dry environment, the safe current-carrying capacity is about 210A, which can meet the power demand of medium-sized industrial equipment and large commercial buildings. The insulation layer thickness is about 1.8mm, and the overall outer diameter is about 16.0mm. This size design can not only ensure the good performance of the insulation layer but also make the wire have certain Flexibility in the wiring process, facilitating 穿梭 in complex power distribution environments.

The 250mm² wire has a conductor diameter of about 18.0mm, and a safe current-carrying capacity of about 350A at 90°C in a dry environment, which can meet the power transmission needs of the main power distribution lines of large industrial enterprises and the total power distribution systems of super-large building complexes. Its insulation layer thickness is about 2.2mm, and the overall outer diameter is about 22.4mm. The thicker insulation layer can provide stronger insulation protection, ensuring safety in high current transmission, and the appropriate overall outer diameter also facilitates the laying and installation of the line.

In addition, the insulation resistance of both specifications of wires is not less than 100MΩ, and the excellent insulation performance can effectively insulate current and prevent electric leakage accidents. They can withstand a high temperature of 90°C in a dry environment and can work normally at 75°C in a humid environment, having good temperature resistance characteristics and being able to adapt to temperature fluctuations that may occur during the long-term operation of the power distribution system. At the same time, the bending radius of the wire is not less than 6 times the outer diameter. The bending radius of the 120mm² specification is not less than 96mm, and that of the 250mm² specification is not less than 134.4mm. This parameter ensures that the wire can be properly bent during wiring, adapting to complex installation environments and reducing construction difficulty.

The 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires, with their strong current-carrying capacity and stable performance, have irreplaceable characteristic uses in many medium and large-scale power distribution scenarios.

The 120mm² wire is suitable for the power distribution systems of medium-sized industrial equipment and large commercial buildings. In medium-sized factories, it can be used as the main power supply line for large production equipment in the workshop, such as providing stable power for CNC machine tools, large compressors, injection molding machines and other equipment. These equipment have large power and high requirements for power stability. The 120mm² wire can stably transmit current, ensuring the normal operation of the equipment and improving production efficiency. In large shopping malls, this specification of wire can be used to connect the main distribution box and the distribution boxes on each floor, efficiently distributing power to various areas. When the air conditioning system, elevators, lighting equipment, etc. in the mall are running at the same time, the power demand is relatively large. The 120mm² wire can meet this concentrated and large power demand, ensuring the normal operation of the mall. In large hotels, it can also be used for the main power distribution lines of the hotel, supplying power to various electrical equipment in guest rooms, restaurants, banquet halls and other areas, ensuring the normal development of various services in the hotel.

The 250mm² wire has a stronger current-carrying capacity and is suitable for the main power distribution lines of large industrial enterprises and the total power distribution systems of super-large building complexes. In the steelmaking workshop of large steel plants, equipment such as steelmaking furnaces and rolling mills have extremely large power and huge power demand. The 250mm² wire can carry huge currents, providing stable power support for these high-power equipment and ensuring the continuous progress of steelmaking production. In the production device area of large chemical enterprises, various reaction kettles, pumps and other equipment need a lot of power to maintain operation. The 250mm² wire can be used as the main power distribution line to ensure stable power transmission and guarantee the safety and efficiency of chemical production. In super-large commercial complexes, this specification of wire, as a line connecting external substations and internal main distribution rooms, can safely introduce and distribute a large amount of power, meeting the power demand of different areas such as shopping malls, office buildings, and hotels in the entire building complex, and is the "main artery" of power supply for super-large commercial complexes. In addition, in large data centers, due to the large number of servers, air conditioners and other equipment with huge power, the 250mm² wire can also play an important role in providing power guarantee for the stable operation of data centers.

The 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires fully consider the needs of medium and large-scale power distribution scenarios in material selection and style design, taking into account performance, safety and practicality.

The conductor is made of high-purity electrolytic copper with a purity of over 99.95%. High-purity copper has excellent conductivity, which can effectively reduce the resistance during current transmission, reduce energy loss, improve power distribution efficiency, and thus reduce the power cost of medium and large-scale industrial and commercial facilities. At the same time, copper has good ductility and toughness, making the multi-stranded twisted conductor not easy to break when bent or stretched, and able to adapt to complex wiring environments, extending the service life of the wire. Compared with conductors of other materials, Copper Conductors have stronger oxidation resistance and corrosion resistance. During long-term use, even in relatively complex industrial environments, they can maintain stable conductivity, providing a solid guarantee for the safe and reliable operation of the power distribution system.

The insulation layer is made of polyvinyl chloride (PVC) material. PVC material has excellent insulation performance, with a volume resistivity greater than 10¹⁴Ω·cm, which can effectively insulate current, prevent electric leakage accidents, and ensure the safety of medium and large-scale power distribution processes. It also has good temperature resistance, can withstand a high temperature of 90°C in a dry environment, and can work normally at 75°C in a humid environment, fully adapting to temperature changes that may occur during the long-term operation of medium and large-scale power distribution systems, without aging and deterioration due to high temperature, ensuring the stability of the insulation effect. In addition, PVC material has certain chemical corrosion resistance, which can resist the erosion of acids, alkalis and other chemical substances that may exist in the power distribution environment, further expanding the application range of the wire in industrial environments.

In terms of style, both specifications of wires have a circular structure, which is cylindrical as a whole with a smooth and flat surface. This structural design makes the wire have low resistance during wiring, easy to thread and pay off, and can easily pass through narrow spaces such as walls and underground pipes of large buildings, improving construction efficiency. The wires are in eye-catching identification colors. The 120mm² specification may be yellow, and the 250mm² specification may be green. Different colors are convenient for electricians to quickly identify wires of different specifications during construction and maintenance, avoid wrong wiring, and ensure the accuracy and safety of the power distribution system.

Multi-strand stranding is an important style feature of these two specifications of wires. The conductor of the 120mm² specification is made of dozens of strands of fine copper wires twisted together, and the conductor of the 250mm² specification is made of more strands of fine copper wires twisted together. This design greatly enhances the flexibility of the wire. Compared with a single-strand conductor, the multi-strand twisted conductor is more flexible when bent, not easy to break, and can adapt to various complex wiring paths, especially at corners and narrow spaces of large buildings, which can better reflect its advantages. At the same time, the multi-strand twisted structure can also reduce the skin effect when the wire transmits current, improve the conductivity efficiency, and reduce energy loss. For medium and large-scale power distribution systems, it can significantly reduce the cost of power transmission.

The production process of the 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires adopts advanced and rigorous techniques to ensure that the product quality meets the high standards of medium and large-scale power distribution scenarios.

The first step is the preparation of copper materials. High-purity electrolytic copper ingots are made into copper rods through processes such as heating and rolling. During the rolling process, the heating temperature is strictly controlled at around 1083°C, which is the melting point of copper, to ensure that the copper ingots are fully melted. At the same time, the rolling speed is precisely controlled to ensure that the diameter of the copper rod is uniform and the mechanical properties are stable, preparing for the subsequent wire drawing process.

Next is the wire drawing process. The copper rod is drawn into multiple strands of fine copper wires by a wire drawing machine. Since the 120mm² and 250mm² specifications require a large number of copper wires with small diameters, the wire drawing process adopts multi-pass drawing, and the drawing die and drawing speed of each pass are precisely calculated and controlled. The drawing die is made of high-strength diamond, which can ensure the dimensional accuracy of the copper wire. A special lubricant is used during the wire drawing process. The lubricant is made of mineral oil mixed with additives, which can effectively reduce friction between the copper wire and the die, prevent damage to the surface of the copper wire, and ensure that the conductivity of the copper wire is not affected.

Then is the stranding process. Multiple strands of fine copper wires are twisted according to a certain stranding method and pitch to form a conductor. The stranding method adopts regular stranding to ensure that each strand of copper wire is evenly stressed and reasonably distributed. For the 120mm² conductor, the stranding pitch is controlled between 30-40mm; for the 250mm² conductor, the stranding pitch is controlled between 40-50mm. A suitable stranding pitch can ensure that the conductor has good flexibility and conductivity. Special stranding equipment is used during the stranding process, and through precise mechanical transmission, the accuracy and stability of stranding are ensured, avoiding phenomena such as loose strands and broken strands.

After stranding, the insulation extrusion process is carried out. PVC material is added to the extruder, heated to 160°C-180°C to melt it, and then evenly extruded and coated on the outside of the conductor through an extrusion die to form an insulation layer. During the extrusion process, the extrusion temperature, speed and pressure are precisely controlled. For the 120mm² wire, the extrusion speed is controlled at 15-20m/min; for the 250mm² wire, the extrusion speed is controlled at 10-15m/min. This can ensure that the insulation layer has a uniform thickness, a smooth surface, is closely combined with the conductor, and has no defects such as bubbles and impurities.

The extruded wire needs to be cooled. The newly extruded wire is quickly cooled to room temperature by means of water cooling to solidify the PVC Insulation layer. During the cooling process, the water temperature is strictly controlled between 20-30°C, and the cooling time depends on the wire specification. The cooling time for the 120mm² specification is about 3-5 seconds, and that for the 250mm² specification is about 5-8 seconds. This avoids cracks in the insulation layer due to too fast cooling or affects production efficiency due to too slow cooling.

The cooled wire also needs to undergo a series of quality inspections, including appearance inspection, size inspection, electrical performance inspection, and mechanical performance inspection. Appearance inspection mainly checks whether the wire surface is smooth, the color is uniform, and there are no scratches, etc.; size inspection uses precision measuring tools to measure parameters such as the outer diameter of the wire, the thickness of the insulation layer, and the diameter of the conductor to ensure they meet the design requirements; electrical performance inspection includes insulation resistance test, voltage withstand test, etc. The insulation resistance test uses an insulation resistance tester to ensure that the insulation resistance is not less than 100MΩ. The voltage withstand test applies 1500V voltage for 1 minute without breakdown; mechanical performance inspection includes tensile test, bending test, etc. to evaluate the flexibility and mechanical strength of the wire, ensuring that it can adapt to various installation and use environments.

The wires that pass the quality inspection enter the coiling and packaging process. The wires are coiled according to the specified length (usually 100 meters or 200 meters), and a coiling machine is used to neatly wind the wires on reels. The reels are made of high-strength plastic or wood materials, which can bear the weight of the wires. Then, the coiled wires are packaged with waterproof and moisture-proof plastic film and put into strong cartons to protect the wires from damage during transportation and storage.

The packaging design of the 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires focuses on protecting the product, facilitating transportation and storage, while emphasizing the clarity of identification and the convenience of use, fully considering the characteristics of medium and large-sized wires.

For coiled wires, due to their large specifications and heavy weight, large hard reels are usually used as inner packaging. The reels are made of high-strength wood or plastic materials. The wooden reels are anti-corrosion treated, which can effectively prevent moisture and decay; the plastic reels have good impact resistance and corrosion resistance. The diameter of the reel depends on the specification and length of the wire. For a 100-meter long 120mm² wire, the reel diameter is about 800mm; for a 100-meter long 250mm² wire, the reel diameter is about 1000mm. Both sides of the reel are equipped with metal baffles with a height of about 100mm, which can effectively prevent the wire from slipping off the reel. After the wire is wound, it is wrapped with a layer of thickened plastic film with a thickness of more than 0.2mm, which has good moisture-proof, dust-proof and wear-resistant properties, and can protect the insulation layer and conductor of the wire from damage during transportation and storage, especially in humid environments, it can effectively isolate water vapor and prevent the wire from getting damp.

For special orders or short-length wires (such as 50 meters), high-strength wooden boxes are used for packaging. The wooden boxes are made of high-quality solid wood boards with a thickness of not less than 15mm, spliced by mortise and tenon structure, which are firm and durable. The inside of the wooden box is fixed and buffered with foam boards according to the shape and size of the wire. The thickness of the foam board is about 50mm, which can effectively absorb the impact force during transportation and prevent the wire from shaking in the wooden box and causing damage. The outside of the wooden box is reinforced with galvanized steel strips with a width of 30mm and a thickness of 1mm to ensure that the wooden box will not fall apart during transportation.

Whether it is reel packaging or wooden box packaging, clear product labels are affixed to prominent positions. The label is made of waterproof and wear-resistant material, with a large size of about 150mm×200mm. It clearly marks the product name (600V Thhn/Thwn stranded copper wire), model, specification (120mm² or 250mm² and length), rated voltage (600V), temperature resistance level (90°C in dry environment), execution standard, production date, batch number, manufacturer name, address, contact information, etc. The text on the label is in large font, clear and eye-catching, and can be seen even from a long distance, which is convenient for users to quickly identify and check product information during receipt, use and maintenance.

For wires transported in batches, multiple reels or wooden boxes are neatly arranged on large transport pallets. The pallets are made of wood or plastic, with a size of 1200mm×1000mm, which can bear a large weight. The reels or wooden boxes are fixed with steel strips between the pallets to ensure that they will not move during transportation. The surface of the pallet is also affixed with eye-catching signs, including product name, specification, quantity, gross weight, net weight, transportation precautions (such as "do not invert", "handle with care", "moisture-proof and sun-proof", etc.), which is convenient for logistics and transportation personnel to load, unload and carry, and also reminds storage personnel to pay attention to relevant matters.

The transportation process of the 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires strictly follows relevant norms and standards. Considering their large specifications and heavy weight, special transportation measures are taken to ensure that the products are delivered to the destination safely and on time.

The transportation method is selected according to the transportation distance, quantity, and customer requirements. For domestic short-distance transportation (usually within 300 kilometers), large flatbed trucks or box trucks are generally used. The truck has a load capacity of not less than 20 tons, with a flat bottom and anti-slip mats laid to prevent the wires from sliding during transportation. When loading, forklifts are used to neatly place the reels or wooden boxes in the compartment. Wires of 120mm² and 250mm² specifications are placed separately. The 250mm² wires with larger specifications and heavier weights are placed at the bottom, and the 120mm² wires with smaller specifications are placed on top. Wooden blocks are placed between the reels, with a thickness of 50mm and a width of 100mm, to avoid collision between the reels. For reel-packaged wires placed horizontally, triangular wooden blocks are used to fix their sides, and the triangular blocks are connected to the compartment side walls with bolts to prevent the reels from rolling. The fixing force should be moderate, which can prevent the wires from moving without excessive extrusion that causes packaging deformation or wire damage.

For long-distance transportation (more than 300 kilometers), railway transportation or water transportation can be chosen. Railway transportation uses boxcars or container transportation. 40-foot dry cargo containers are selected, which can accommodate a large number of wires. When loading, the reels or wooden boxes are neatly arranged in the container and fixed to the container's side walls or bottom with steel strips to ensure no displacement during transportation. Water transportation is suitable for cross-regional or coastal transportation. The wires are loaded into the cargo hold of the freighter, and the cargo hold is moisture-proof and salt-fog resistant. A layer of waterproof canvas with a thickness of 0.5mm is covered on the outside of the packaging, which has good waterproof performance, further enhancing the moisture-proof effect and preventing seawater or moisture from eroding the wires.

During transportation, a series of measures are taken to prevent the wires from being affected by adverse environmental factors. When transporting in summer, due to high temperatures, the wires should be avoided from being exposed to direct sunlight for a long time. A sunshade made of sun-proof canvas can be installed on the top of the truck or inside the container to effectively block direct sunlight, reduce the internal temperature, and prevent the PVC insulation layer from accelerating aging due to high temperatures. When transporting in winter, if the temperature is too low (below -10℃), the wires should be avoided from severe impact, because low temperatures will reduce the toughness of PVC materials, making them prone to brittle fracture. During loading and unloading, special lifting equipment such as cranes and forklifts are used to lift and place gently, avoiding collision between the wires and other objects. When transporting in rainy or humid weather, it is necessary to ensure that the transportation tool has good sealing performance. The doors and windows of the truck compartment or container are tightly closed to prevent rainwater from entering. At the same time, check whether the wire packaging is intact. If there is any damage, repair or replace the packaging in a timely manner.

Transportation personnel must receive professional training and be familiar with the characteristics and transportation requirements of the wires. Before transportation, a comprehensive inspection of the loading situation is carried out, including whether the wires are firmly fixed, whether the packaging is intact, and whether the signs are clear. During transportation, strictly abide by traffic rules, avoid sudden braking, sharp turns, overloading, and other behaviors that may cause damage to the wires. For long-distance transportation, stop regularly to check the condition of the wires. If loose fixing, packaging damage, or wire displacement is found, handle it in a timely manner. In case of severe weather such as heavy rain, snowstorm, or typhoon during transportation, stop at a safe place and continue transportation after the weather improves.

The shipping process of the 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires is scientific and standardized, committed to providing customers with efficient and accurate logistics services.

After the customer places an order, the sales staff will conduct a detailed review of the order information, including the wire specification (120mm² or 250mm²), quantity, delivery time, delivery address, recipient, and contact information. If there is any ambiguous information in the order, the sales staff will promptly communicate with the customer to confirm, ensuring that the order information is accurate and complete and laying a good foundation for the smooth progress of subsequent shipping work.

After the order is confirmed, the sales department will issue a picking list to the warehouse department. The warehouse staff will check the inventory according to the picking list. If the required wires are in stock, they will immediately start picking. During the picking process, carefully check the product labels to ensure that the specification, batch number, and production date of the picked wires are consistent with the order requirements. At the same time, inspect the packaging of the wires to ensure that the reels or wooden boxes are intact, without damage, moisture, or other phenomena that may affect the quality of the wires.

If the required wires are out of stock, the warehouse department will feedback to the sales department in a timely manner, and the sales department will negotiate with the production department. The production department will formulate a production plan according to the order urgency and arrange production as soon as possible to ensure that the wires are produced and stored in the warehouse within the agreed delivery period. During the production process, the sales staff will keep in touch with the customer, inform the customer of the production progress, and let the customer know the estimated shipping time, so that the customer can arrange the receipt work in advance.

After the wires are picked or produced and put into the warehouse, the warehouse department will pack them according to the specified packaging standards. For reel-packaged wires, check whether the plastic film is wrapped tightly and whether the metal baffles on both sides of the reel are firm. For wooden box-packaged wires, check whether the foam board inside is properly filled and whether the galvanized steel strips outside are tightly bound. After packaging, make a detailed shipping list, which includes the product name, specification, quantity, weight, packaging type, and other information, and then hand over the wires and the shipping list to the logistics department.

The logistics department will choose the appropriate transportation method and carrier according to the delivery address and the customer's requirements for the arrival time. For urgent orders, priority is given to special vehicle transportation to ensure that the wires can be delivered to the customer within the specified time. For ordinary orders, choose economical and reliable transportation methods to reduce transportation costs for customers. After determining the transportation plan, go through the relevant procedures such as transportation contracts and cargo insurance.

Before shipping, the sales department will send the shipping information to the customer via phone call, SMS, or email, including the shipping time, transportation method, carrier name, waybill number, estimated arrival time, and contact information of the driver (for road transportation). The customer can track the logistics information in real-time through the waybill number and prepare for receipt.

After the wires arrive at the destination, the customer should check the outer packaging for damage, and then check whether the quantity and specification of the wires are consistent with the order. If there is any problem, contact the sales department or logistics department in a timely manner to deal with it. After the customer confirms that there is no problem, sign for receipt.

Providing samples of 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires is an important part of pre-sales service, helping customers understand the product's performance and quality, and making purchase decisions.

Customers who need samples can apply to the company's sales department through the official website, phone, email, and other channels. When applying, they need to provide basic information such as the required wire specification (120mm² or 250mm²), the purpose of the sample, the company name, contact person, and contact information. The sales department will review the customer's application. For legitimate business customers, free samples (usually 1-2 meters per specification) can be provided, but the customer needs to bear the shipping cost. For customers who need a large number of samples or have special requirements, the specific sample fee and shipping cost can be negotiated separately.

After the sample application is approved, the warehouse department will select wires that meet the quality standards from the qualified products as samples. The samples must be representative, with complete packaging and clear labels, consistent with the formal products in terms of material, structure, and performance. Before sending the samples, the quality inspection department will conduct a simple inspection on the samples, including checking the appearance of the insulation layer, the tightness of the conductor stranding, etc., to ensure that the samples are in good condition.

The samples are usually shipped by express delivery, which is fast and convenient, and can ensure that the samples reach the customer in a short time. The common express companies include DHL, FedEx, UPS, etc., and the appropriate express company is selected according to the customer's location. After the samples are shipped, the sales department will promptly inform the customer of the express waybill number and estimated arrival time, so that the customer can track the sample logistics information.

After the customer receives the sample, if they have any questions about the sample's performance, installation, or use, they can contact the company's technical support personnel. The technical support personnel will provide professional answers and guidance based on the customer's feedback, such as explaining the wire's current-carrying capacity, installation precautions, etc., to help the customer better understand the product.

The 120mm² and 250mm² specifications of 600V Thhn/Thwn stranded copper wires have a complete after-sales service system to provide customers with comprehensive technical support and problem-solving services, ensuring that customers can use the products with confidence.

The product warranty period is 12 months from the date of delivery. During the warranty period, if the wire has quality problems such as insulation layer damage, conductor breakage, or abnormal electrical performance due to manufacturing defects, the customer can contact the after-sales service department for processing. When reporting a problem, the customer needs to provide relevant information such as the purchase contract number, product batch number, problem description, and photos or videos of the problem, so that the after-sales department can quickly identify the problem.

After receiving the customer's complaint, the after-sales service department will respond within 24 hours and arrange professional technicians to handle it. The technicians will analyze the problem through telephone communication, video calls, or on-site investigation. If it is confirmed that it is a product quality problem, the company will provide solutions such as return, replacement, or repair according to the actual situation. For return or replacement, the company will arrange for the return of unqualified products and send qualified products to the customer within the agreed time, and bear the relevant transportation costs. For repairable problems, the technicians will provide on-site repair services or guide the customer to repair through remote guidance.

If the problem is caused by improper use, installation, or storage by the customer (such as exceeding the rated current, incorrect bending radius, or damage caused by mechanical external force), the after-sales service department will also actively provide technical guidance and solutions, but the customer needs to bear the relevant costs. The technical staff will explain the correct use methods and precautions to the customer to avoid similar problems from happening again.

In addition to handling quality problems, the after-sales service department also provides long-term technical consultation services. Customers can consult the after-sales staff about wire maintenance, installation specifications, performance parameters, and other issues at any time. The after-sales staff will provide professional answers based on their professional knowledge and practical experience.

The company will also conduct regular return visits to customers. Through phone calls, emails, or on-site visits, understand the use of the wires and the customer's opinions and suggestions on the product and service. According to the customer's feedback, continuously improve the product quality and service level, and enhance customer satisfaction.

The after-sales service team is composed of experienced technicians and customer service personnel who have received professional training and are proficient in product knowledge and service skills. They adhere to the service concept of "customer first" and are committed to solving various problems for customers in the process of using the product.