125℃ to 450℃ high
temperature wire and cable

125°C to 450°C high temperature wire and cables are especially designed and manufactured with the top grade materials to provide the best service in the high heat situations with no errors.

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Teflon wire (FEP PFA PTFE)

Teflon wire (FEP PFA PTFE)

Teflon is good for 125°C to 450°C high temperature wire and cable. It uses heat-rated fluoropolymer insulation such as FEP, PFA or PTFE. FEP is usable up to 200C. PFA can be used up to 260°C. A rough cycle can push PTFE to temperatures of 260°C or more. They are resistant to chemicals, acids or oils. They are not made soft by excess of heat. It remains soft and flexible, even after extended use. Teflon insulation for high temperature wire retains a high dielectric strength. Ideal for installation of sensor leads and high temperature heater wire. For high temperature lead wiring in control panels, Teflon wire is also used. Engineers often use this method when they need reliability under continuous heat stress.

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Fiber glass braided wire

Fiber glass braided wire

This fiberglass braided wire is excellent for radiant, convection and dry heat. The base insulation and conductor are surrounded by a tight glass braid. Some types can survive at temperatures as high as 450°C. It is ranked as a leader among manufacturers of 125°C to 450°C high temperature wire and cable worldwide. The braid does not melt. Shrinkage is not a problem. It retains its shape even when put directly on heat. This material is widely used as heat resistant wire in ovens, kilns, furnaces and dryers. The outside of the wire is resistant to abrasion, extending the service life of the wire. Fiberglass braided wire is an excellent alternative to high temperature wire sleeving for tight spaces.

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Mica wrap + Fiber glass braids

Mica wrap + Fiber glass braids

The mica wrap and fiberglass braiding combine to form a strong dual-barrier insulation system. Mica tape applies directly to conductor, essential for fire and heat protection. Outer fiberglass braid provides mechanical shield and structural backbone. They are among the most effective compounds insulating 125°C to 450°C high temperature wire and cables. This design resists continuous use up to 450 °C. Approved for fireproof circuits. The outer jacket can be burned off, but the mica-glass wire still works. It serves industrial safety wiring, emergency lighting and fire alarm systems, meeting international fire survival standards.

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Why use QL-Custom’s high temperature wire and cables

Why use QL-Custom’s high temperature wire and cables

Since 2011, we are providing teflon wire and cable for American Thermocouplecustomers

Since 2011, QL-Custom Technology Ltd. has served many North American buyers for high temperature thermocouple wire. US shoppers buying thermocouples seek accuracy and cables preserving signal integrity under high heat. We’ve calibrated thousands of meters of graded thermocouple cable, maintaining tight tolerances to retain repeat clients. Understanding consistent high-temp wiring measurement matters, we enforce strict full-process quality checks and build long-term on-spec partnerships. Boasting over 14 years’ experience, we deliver premium 125°C–450°C high-temperature wire and cable.

We have new technologies to strip the FG wires, reject finger allergy

The only real downside to fiberglass wire is itch from tiny glass fibers during handling or stripping. QL-Custom fixed this with a new mechanical stripping method for clean fiberglass ends: no unpeeling, fibers stay set, safe for workers’ hands. It cuts installation time and frayed wire waste, working for all fiberglass wire diameters. Most 125°C–450°C high-temp cable makers overlook this practical upgrade, which troubled us. Our refined solutions let customers install faster and safer.

We updated 150+ solutions for high temperature device

Over the years we’ve refined over 150 unique high-temperature device wire solutions, spanning multi-conductor cables, bespoke jacketed bundles and high-temp loom assemblies. Our clients build heating, testing and processing gear; products match each unit’s electrical needs, space limits and thermal traits. We skip standard stock, resolving issues case by case. Our engineers study every application to tailor suggestions. This consultative method cuts breakdowns, boosts runtime and lifts safety. Honest innovation over shortcuts lets us meet rising demand for 125°C–450°C high-temperature wire and cable jackets.

High temperature wire different materials

Nickel plated conductors

Nickel plated conductors

Nickel-plated conductors serve temperatures over 200 °C; nickel shielding guards copper against high-temp oxidation. Unplated copper rapidly oxidizes in hot air, spiking resistance and signal faults. The plating forms a tough barrier surviving repeated thermal cycling, an industry norm for precision sensor leads and high-temperature thermocouple wire. High-temp insulators like PTFE bond better to nickel-plated wire, pairing with most high-heat crimp connectors. Plating thickness dictates ruggedness in harsh conditions; reach out for custom plating specs.

How to select temperature resistant color Toner

How to select temperature resistant color Toner

The color coding on high temperature electrical wire is not merely for organization, built to withstand extreme heat. Conventional PVC inks transfer, break or fade above 105°C. Color toner bonds into high temperature wire insulation during extrusion. Fluoropolymer wires blend pigments directly into fluoropolymer. Colored yarn or dyed glass serve braiding for fiberglass wires. The colour stays legible after 1000+ hours heating. This covers compliance audits, safety tracking and maintenance. We follow UL and IEC color standards. OEM customers needing custom harness colors can do so.

Which fiber glass can be used for wires

Which fiber glass can be used for wires

Fiberglass has many grades. Braided wire and high-temperature sleeving use E-glass, with strong tensile strength and heat resistance to 450°C as key merits. S-glass outperforms ordinary glass mechanically at equal temperatures. Fragile silica glass works above 500 C for extreme heat. Fiber count and braid tightness impact flexibility and abrasion resistance. Resin-treated fiberglass resists moisture for damp/outdoor use. Unfinished fiberglass is air-permeable, ideal for oven or furnace interiors. We pick proper fiber for your application for precise cable signal transmission.

Mica tapes for Mica wire

Mica tapes for Mica wire

No fireproof wire design is complete without mica tape. The two most common types are phlogopite and muscovite. Certain phlogopite grades withstand temperatures up to 900°C. Muscovite has better electrical insulating properties. Cable mica tapes have paper or glass backing. Glass-backed mica tape reinforces the wrap mechanically. The tape winds helically around conductors with overlaps. Proper overlap prevents heat-expansion gaps. Mica tapes in our high-temperature cables meet IEC 60371. Thickness and ply count depend on the wire’s voltage rating and temperature class.

The features of Teflon coated and Fiber glass insulated

The feature of Teflon wire

Teflon wire is excellent at resisting both high temperatures and chemicals. It runs well from 125°C to 260°C (depending on grade). The surface is non-stick so no contamination occurs in food or pharmaceutical settings. It’s ideal for data and signal cables due to its very low dielectric constant. Teflon wire is fireproof and can even put out fires on its own. It also weighs less than rubber insulated ones. These properties make it the preferred high temperature lead wire for instrumentation and control systems.

The feature of Teflon wire

The feature of Fiber glass wire

For high temperature applications fiber glass wire is the lightest and most bulk free. It can be continuously exposed to a temperature as high as 450°C without any degradation. The braid is resistant to mechanical stress and will not be worn through by metal conduit or edges. When heated it does not burn or release any harmful gases. Fiber glass wire is pliable. This makes it easy to route inside of ovens and other appliances. It is mainly used as heat resistant wire by oven and kiln builders.

The feature of Fiber glass wire

The feature of mica tape wires

Mica tape wire should be used only for fire escape circuits The layered structure would protect the conductors no matter how hot the outer material gets. The rating class defines the length of time it maintains electricity to the circuits of the fire – 30, 60 or 90 minutes. The insulation withstands the impact of water-jet firefighting without deterioration. Mica wire is used in situations where life saving systems have to be kept on. It also has excellent resistance to partial discharge at high voltage.

The feature of mica tape wires

Industries and Applications

Industrial Furnaces & Kilns

Industrial Furnaces & Kilns

Internal wiring, heating element leads and thermocouple connections for industrial kilns and furnaces used to make ceramics, glass or metal require continuous-rated high-temperature resistant wire up to 450 degrees C.

Aerospace & Defense

Aerospace & Defense

In the aerospace and defense industries avionics harnesses, actuator leads and engine bay wiring are made from lightweight nickel-conductor cables and Teflon that can withstand the rigors of flight such as heat, fluid.

Home Appliances & Commercial Ovens

Home Appliances & Commercial Ovens

Insulation resisting daily thermal cycling is a necessity—especially for heater connections and high-temperature heater wire in appliances like ovens, grills, toasters and dryers.

Automotive & EV Systems

Automotive & EV Systems

High temperature wire loom systems are used in automotive and electric vehicle systems and are critical to under-hood wiring, motor leads and battery thermal management circuits, and able to withstand engine heat, chemicals, decades of service cycles.

Fire Safety & Emergency Systems

Fire Safety & Emergency Systems

Controls of suppression system, emergency lighting and fire alarm panels use mica-glass survival 125°C to 450°C high temperature wire and cable with circuit integrity rating to maintain circuit integrity in fire.

Semiconductor & Test Equipment

Semiconductor & Test Equipment

Semiconductor test equipment features precision signal cables & high-temp thermocouple wire providing accurate, drift-free measurement in environmental, calibration and wafer processing chambers.

Major Failures of Most Cable & Our Solution

Thermal aging cracks insulation

Over time heat causes the polymer chains to break down , causing the insulation to crack . The wire seems good but the insulation is brittle. There is a problem with the initial vibration.

Oxidation raises resistance

Resistance is increased by oxidation. Copper conductors unplated oxidize at a steady rate in heated air. Increasing difficulty. The equipment gets hot. Energy prices go up. If a sensor goes out, no one will ever know.

Wrong temperature rating shortens life

Running a 105C rated wire at 180C instead 125°C to 450°C high temperature wire and cable will age it 8 - 10 times faster and reduce its life. no, years. It may survive months, not years.

Our solution

Our solution

The solution we developed is to define the correct wire according to the real operating temperature, not the nominal one. Insulation grades are proper, temperature ratings are checked, and conductors are nickel-plated. We guarantee all our 125°C to 450°C high temperature wire and cable products are compatible with the real temperature of your device. We help you stop failure before it can even begin.

Low Smoke, Zero Halogen, Full Circuit Integrity

Low smoke output

Our fiberglass and mica wires emit very little smoke when subjected to heat or flame. This helps to protect personnel and equipment in confined spaces.

Zero halogen formula

In case of fire, avoid the emission of dangerous gases by using halogen-free insulation. This is what underpins tunnels, ships, public structures and data centers.

Rated to 450°C

Designed for continuous operation at temperatures as high as 450°C, our premium products. They are also thermally cycled and fully stable when returned to ambient temperature.

No jacket compromise

It is essential that materials used in the high-temperature wire and cable jacket industry be bendable without cracking. We do peak and cycle thermal performance tests on our jackets.

Full circuit integrity

Circuits can remain live in fires with fire-survival 125°C to 450°C high temperature wire and cables made of mica. Fire resistant as certified for 30-90 minutes under IEC regulations.

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Tested to IEC 60216 & Shipped with the Data

The thermal stability of the insulating material was evaluated according to IEC 60216, the global standard for thermal aging.

The test report for each batch includes a temperature index, thermal aging results and mechanical retention data.

The conductor resistance is given in accordance with the tolerances approved by IEC 60228 and not as estimated values.

Flame and fire tests on suitable products are performed in accordance with IEC 60332 and IEC 60331.

The thickness of the insulating wall was determined according to IEC 60811.

Tested to IEC 60216

Customer Reviews

★★★★★

We switched to QL-Custom's PTFE wire two years ago for our kiln control systems. The quality is consistent order after order. No insulation cracking, no signal drift from the thermocouple leads. This is the standard we now require from all suppliers.

James R. Whitfield

James R. Whitfield

★★★★★

QL-Custom gave us competitive pricing on mica-glass fire survival cable without cutting corners on certification. The IEC test data came with every shipment. That level of documentation makes our compliance audits smooth and fast.

Maria Evangelista

Maria Evangelista

★★★★★

We were struggling with fiber glass wire causing skin irritation on our assembly line. QL-Custom's new stripping process solved it completely. Our team now installs faster and no one is complaining about finger irritation anymore.

David Chen

David Chen

★★★★★

We use QL-Custom for all our oven heater wire needs. Their FEP and fiber glass products handle our continuous 300°C duty cycles without issue. Reliable, certified, and always in stock when we need it.

Sophie Hartmann

Sophie Hartmann

★★★★★

Before QL-Custom, we had two or three wire failures per month in our furnace room. After switching to their nickel-plated fiber glass wire (125°C to 450°C high temperature wire and cable), we have had zero failures in 18 months. The difference is night and day.

Carlos Mendez

Carlos Mendez

★★★★★

I have used several high temperature cable suppliers over the years. QL-Custom stands out for one reason: they actually know their product. When I called with a technical question about mica tape ratings, I got a real engineer on the phone with a real answer.

Tom Briggs

Tom Briggs

The Worthy Site for Maximum Grade Cables

QL-Custom Technology Ltd. doesn’t sell products by catalogs. Thermal wire engineering is one of the many partnerships we have.” Since 2011 we have been helping engineers, original equipment manufacturers and procurement teams to source the most cost effective and accurate 125°C to 450°C high temperature wire and cable solution for applications from 125°C to 450°C. Get Teflon wire in FEP, PFA or PTFE grades. We've got them all. We produce fire survival cables in the form of mica and fiberglass of various geometrical shapes. Our staff will consider your temperature range, mechanical needs and compliance requirements to provide the best recommendation possible.

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