# HIGH TEMPERATURE CABLES URL: https://www.chinneelectric.com/products-types/high-temperature-cables/ Brand: Chinne Electric ## Summary High temperature cables are engineered electrical conductors designed to withstand continuous operating temperatures above 150°C, often reaching 200°C to 260°C or higher. A trusted factory-direct supplier, Chinne Electric offers fluoropolymer-insulated (PTFE, FEP, PFA) and silicone rubber (SRML) cables that maintain dielectric integrity and mechanical stability in extreme heat, per IEC and UL thermal classes, utilizing plated copper conductors to prevent oxidation and ensure reliable power delivery in industrial motors, furnaces, and commercial ovens. ## Key facts - PTFE-insulated cables are rated up to 260°C and provide the highest chemical resistance among fluoropolymers, per UL 1180 and UL 1332 style classifications. - Silver-plated copper conductors are standard for FEP and PTFE cables up to 200°C–250°C to prevent oxidation, while nickel-plated copper enables operation up to 450°C+ in TGGT and MGT constructions. - SRML (Silicone Rubber Motor Lead) cable uses a fiberglass braid over silicone insulation to resist tearing during installation in motor stators, rated for 150°C to 200°C. - FEP melt-extrusion allows a 20–30% smaller diameter than conventional wires, making it suitable for tight-space applications at ratings up to 200°C. - TGGT (Teflon Glass Glass Teflon) cable is rated for continuous use at 250°C and is preferred for commercial ovens and industrial heaters due to its resistance to chemical vapors. ## FAQ ### How do Chinese (GB) and International naming conventions for high-temperature cables differ? In the international market, high-temperature cables are identified by their material acronyms (like PTFE, FEP), their UL AWM style numbers (e.g., UL 3122), or IEC classifications. The Chinese system uses the GB (Guobiao) standard, relying on specific Pinyin initials to indicate the chemical makeup of the insulation. Chinese System (GB/T): Common models include AF (Fluoroplastic insulation), YG (Silicone rubber), and GN (Fire-resistant/Mica). For instance, an AF-200 indicates a fluoroplastic wire rated for 200℃. International System (UL/IEC/CSA): Uses acronyms describing the exact construction or UL styles: Fluoropolymers: PTFE, FEP, PFA (Often classified under UL 1180, UL 1332). Silicone Rubber: SRML, SF-2, SFF-2. Extreme Heat: TGGT (Teflon Glass Glass Teflon), MGT (Mica Glass Tape). Global Interchangeability: Despite differing names, these cables can be used interchangeably in global projects. Performance is dictated by thermal endurance, dielectric strength, and conductor plating. As long as the physical materials (e.g., Silver-plated copper with PTFE) and the temperature/voltage ratings match the project's engineering specifications, the cables meet the universal physical laws of thermal degradation. ### What are the primary differences between PTFE, FEP, and PFA fluoropolymer cables? While all three are high-performance fluoropolymers, they serve different manufacturing and installation needs: PTFE (Polytetrafluoroethylene): Rated up to 260℃. It offers the highest chemical resistance and lowest friction but must be tape-wrapped or ram-extruded, making it slightly stiffer. FEP (Fluorinated Ethylene Propylene): Rated up to 200℃.. It is melt-extrudable, allowing for long continuous lengths and a 20-30% smaller diameter than conventional wires, perfect for tight spaces. PFA (Perfluoroalkoxy): Rated up to 250℃.. It combines the superior extreme-heat rating of PTFE with the extrusion flexibility of FEP. ### Why is standard bare copper rarely used in cables rated above 150℃? Bare copper oxidizes rapidly at elevated temperatures, leading to increased electrical resistance, brittle conductors, and eventual termination failure. In the international market, high-temperature cables utilize strictly plated conductors: Tinned Copper: Standard for general silicone cables up to 150℃. Silver-Plated Copper (SPC): Provides excellent conductivity and prevents oxidation; the standard for FEP and PTFE cables up to 200℃ - 250℃. Nickel-Plated Copper (NPC): Withstands extreme heat up to 450℃+$ without oxidizing. Mandatory for MGT and TGGT cables. ### What is SRML cable and where is it typically applied? SRML (Silicone Rubber Motor Lead) is a highly flexible cable rated for 150℃ to 200℃ . Because silicone is mechanically soft, SRML features a tightly woven fiberglass braid over the insulation. This prevents the silicone from tearing when being forcefully pulled through the tight stators of electric motors. It is the industry standard for high-power generators, industrial motors, and heavy-duty lighting fixtures. ### What does TGGT stand for, and when should engineers specify it? TGGT (Teflon Glass Glass Teflon) is rated for continuous use at 250℃. Construction: It consists of a nickel-plated copper conductor, wrapped in PTFE tapes, covered by a fiberglass wrap, and finished with a PTFE jacket. Application: It handles extreme heat and is highly resistant to chemical vapors, making it the preferred choice for commercial ovens, industrial heaters, and glass kilns. However, it lacks the dynamic flexibility of silicone. ### How does an MGT cable achieve a continuous 450℃ temperature rating? MGT (Mica Glass Tape) operates in environments where standard polymers literally melt or vaporize. It utilizes Mica tape—a natural, fire-resistant mineral—wrapped directly around a nickel-coated conductor, which is then protected by a high-temperature fiberglass braid. It is exclusively used in ultra-high-heat zones like iron and steel mills, cement kilns, and foundries. ### What is the difference between SF-2 and SFF-2 silicone wires? Both are standard Appliance Wiring Materials (AWM) made of silicone and fiberglass, but they differ in mechanical flexibility (the extra "F" stands for Flexible): SF-2: Utilizes a solid or standard stranded conductor (Class B or C). Best for fixed internal wiring. SFF-2: Utilizes a highly flexible stranded conductor (Class H or K). It is ideal for tight routing in small lighting fixtures or appliances subject to vibration. ### How does the "Cold Flow" (creep) characteristic affect fluoropolymer cable installation? Fluoropolymers (like PTFE and FEP) have a very low coefficient of friction and can slowly deform (creep) under continuous mechanical pressure. If over-tightened with thin cable ties or sharp compression clamps, the insulation can thin out over time, reducing its dielectric strength and causing a short circuit. Engineers must use broad-surfaced clamps or dedicated routing channels to distribute pressure evenly. ### What are the best practices for routing high-temperature cables in metal cable trays? Because these cables operate in extreme heat, their installation in cable trays, trunking, or strut channels requires strict thermal management: Heat Dissipation: High-temp cables rely on ambient air to cool. Wire mesh cable trays or perforated metal cable ladders are vastly superior to solid-bottom trunking because they maximize airflow. Spacing Rules: Cables should be installed in a single, flat layer with adequate spacing (often 1x to 2x the cable diameter) between them. Bunching them together creates a "heat trap" that can push the internal temperature beyond the cable's maximum rating. ### Are high-temperature cables automatically "Fire-Resistant"? No. This is a critical engineering distinction. High-Temperature Cables (like Silicone or PTFE) are designed to operate continuously in high ambient heat (e.g., 200℃). However, if exposed to direct flames, a standard silicone cable will eventually burn. Fire-Resistant Cables (like IEC 60331 compliant cables) are designed to survive direct fire (up to 950℃) for a specific duration (e.g., 2 hours) to maintain critical emergency life-safety circuits. ### How does high ambient temperature affect the Ampacity (current carrying capacity) of the cable? Ampacity ratings are typically calculated based on a baseline ambient temperature of 30℃. As the surrounding environment gets hotter, the cable's ability to dissipate its own internal electrical heat (I²R loss) diminishes drastically. Engineers must apply a Temperature Derating/Correction Factor. For example, a wire safely carrying 100 Amps at 30℃ may only be rated to safely carry 60 Amps in a 90℃  boiler room. ### Why do silicone-insulated cables often feature a fiberglass over-braid? While silicone rubber provides exceptional flexibility and heat resistance (up to 200℃), its mechanical tensile strength is relatively low. It is susceptible to abrasion, tearing, and "cut-through." A woven fiberglass braid acts as mechanical armor, protecting the silicone core from physical damage when dragged across industrial floors or pulled through rough steel conduits. ### Can high-temperature wires also be used in extremely low (cryogenic) temperatures? Yes, depending on the chemical composition. Fluoropolymers (PTFE, FEP) and Silicone maintain their molecular flexibility in extreme cold, often retaining their ratings down to -60℃ or even -90℃. Unlike standard PVC, which embrittles and shatters in sub-zero environments, these cables are ideal for aerospace, arctic infrastructure, and cryogenic gas facilities. ### What is the significance of the UL AWM classification for international buyers? In the international market, many high-temperature wires are classified under UL 758 as Appliance Wiring Material (AWM). This means they are Recognized Components intended specifically for the internal wiring of factory-assembled equipment (like industrial ovens, HVAC systems, or control panels), rather than for general building wire pulled through walls. Each AWM "Style" dictates the precise voltage, temperature limit, and insulation thickness. ### How do I choose between an extruded jacket and a taped/braided jacket for high-temp environments? The choice depends on the presence of moisture and mechanical wear: Extruded Jackets (FEP, PFA, Silicone): Provide a seamless, watertight barrier. They are mandatory for environments involving steam, high humidity, or chemical wash-downs. Taped/Braided Jackets (PTFE Tape, TGGT, MGT): Provide higher absolute temperature resistance but are not inherently watertight, as moisture can penetrate the fiberglass braids. They are best suited for completely dry, extreme-heat zones like kilns or furnaces.