High Temperature Mica Fiber Braided Furnace Cable (400°C–500°C)
High temperature mica fiber braided furnace cable is a specialised inorganic-insulated cable constructed for internal wiring of industrial furnaces, kilns, smelting equipment, and other high-temperature heating systems operating continuously at 400°C to 500°C. The cable is built around a non-extruded mica tape insulation system — multiple layers of phlogopite mica tape wound directly over the copper conductor — combined with a treated fiberglass braid outer covering that provides both mechanical protection and additional thermal insulation.
Unlike silicone rubber or PTFE wire, which use organic polymer insulations that char and lose electrical integrity above 260°C, mica tape insulation is a pure mineral construction with no organic components. The mica mineral itself has a melting point exceeding 700°C and retains its crystalline structure and electrical insulating properties throughout the 400–500°C operating range of this cable. Even in the event of a thermal overload that destroys the fiberglass braid outer covering, the mica insulation layers remain intact, preventing short circuits and equipment damage at the critical moment when electrical integrity matters most.
Produced at our Yangzhou facility under UL Follow-Up Service File No. E333030, this cable range is recognised under UL AWM Styles 5107, 5128, 5334, and 5476 — covering 300V to 600V AC at temperature ratings of 200°C to 450°C across the full AWG range from 30 AWG to 550 kcmil.
UL AWM Style Reference — Certified Specifications
| UL Style | Temp | Voltage | AWG range | Mica tape (26–12 AWG) | Glass braid |
|---|---|---|---|---|---|
| 5107 | 200°C or 450°C | 600V AC | 26 AWG–550 kcmil | 25 mils min avg | 7 mils min avg |
| 5128 | 450°C | 300V AC | 24 AWG–4 AWG | 15 mils min avg | 7 mils min avg |
| 5334 | 450°C | 300V AC | 24 AWG–4 AWG | 17 mils composite | 5 mils min avg |
| 5476 | 450°C | 600V AC | 30 AWG–4/0 AWG | 17 mils min avg | 7 mils min avg |
Reprinted from Product iQ with permission from UL Solutions. ©2026 UL LLC. File No. E333030, last updated 2025-12-01.
Technical Specifications
| Parameter | Specification |
|---|---|
| Temperature rating | 400°C to 500°C (product range); UL certified to 450°C |
| Voltage rating | 300V AC or 600V AC (style dependent) |
| Conductor material | Solid or stranded copper (nickel-plated optional at highest temp) |
| AWG / size range | 30 AWG – 550 kcmil (style dependent) |
| Insulation type | Non-extruded mica tape, multiple layers |
| Outer covering | Treated fiberglass braid (silicone varnish or PTFE finish) |
| Optional shield | Stainless steel 304 braid (5128, 5334, 5476) |
| Flame rating | Horizontal flame |
| Fire resistance | Mica insulation maintains integrity at direct flame exposure |
| Standard | UL AWM 5107/5128/5334/5476, GB/T 13033, RoHS |
| Installation type | Fixed static — not suitable for repeated flexing |
| Packaging | 10 m / 25 m / 50 m coils or cut to length |
Key Features
Extreme thermal performance
- 400°C–500°C continuous operating range
- Mica insulation — will not burn, melt, or carbonise
- Maintains electrical integrity above rated temperature in overload
- No organic components — zero off-gassing at operating temperature
- Dimensionally stable through repeated thermal cycling
UL recognition & construction
- UL 5107, 5128, 5334, 5476 — File No. E333030
- Multiple mica tape layers for redundant insulation
- Treated fiberglass braid — SiVa or PTFE finish options
- Optional SS304 braid for mechanical protection
- 30 AWG to 550 kcmil — full range coverage
- Purpose-built for furnace wiring — the only cable construction rated for 400°C–500°C continuous static installation
- Multi-conductor assembly available — up to 1.5″ OD with mica glass binder for multi-circuit furnace wiring in a single cable
- Static installation only — mica tape is not flexible; install once and do not flex during service
Common Applications
Industrial furnace and kiln element wiring
The primary application is internal wiring inside industrial furnaces operating at 400°C to 500°C — connecting resistance heating elements to terminal blocks, routing temperature sensor leads through the furnace hot zone, and providing control signal connections for motorised dampers and atmosphere valves inside the furnace chamber. At these temperatures, no silicone, PTFE, or any other organic polymer cable can survive continuous service.
Metal smelting and foundry equipment
Used for wiring inside induction melting furnaces, arc furnaces, and resistance melting equipment in foundry and metal processing operations where the wiring zone consistently exceeds 400°C and the combination of high temperature, radiant heat, and occasional metal splash demands inorganic insulation with demonstrated fire integrity.
Ceramic and glass manufacturing
Specified for internal wiring of ceramic firing kilns, glass melting furnaces, and glass annealing lehrs operating at 500°C+ process temperatures where the wiring zone — even away from the direct firing zone — sustains 400–480°C ambient temperature throughout extended production runs.
Heat treatment furnaces
Used in vacuum heat treatment, atmosphere annealing, and salt bath furnaces for the thermocouple leads, heating element connections, and atmosphere valve wiring that must operate continuously at 400°C to 500°C throughout the treatment cycle.
Other applications
- Induction heating coil lead connections
- Semiconductor diffusion and CVD furnace internal wiring
- Cremation equipment internal electrical connections
- High-temperature laboratory furnace wiring
Ordering Information
Specify UL style (5107, 5128, 5334, or 5476), temperature grade (200°C or 450°C), voltage (300V or 600V), AWG/kcmil size, optional stainless steel braid, and required length. Multi-conductor assemblies from 200 m MOQ. Cut to length from 1 m for maintenance replacement.
UL compliance documentation on request. Test reports and material certificates supplied. Contact us for pricing within 24 hours.
Why Choose CableApex
CableApex manufactures mica fiber braided furnace cable under UL Follow-Up Service (File No. E333030) for Styles 5107, 5128, 5334, and 5476. Mica tape is sourced from certified phlogopite suppliers with controlled overlap on dedicated winding lines. All production is tested for insulation resistance and dielectric withstand voltage. We supply to furnace manufacturers, kiln builders, foundry equipment OEMs, and specialist contractors across more than 40 countries.
