UL 5476 High-Temperature Equipment Wire Overview
UL AWM Style 5476 is a single or multiple conductor construction with other-than-extruded insulation, covering 30 AWG through 4/0 AWG, solid or stranded, rated 450°C and 600 Vac with Horizontal Flame. The construction is mica tape with a glass braid treated with silicone varnish or TFE finish.
This page is the base technical product page for that Style: the full conductor range, the verified ratings, and the three UL-defined construction bands that sit inside the range. The application context is fixed, mechanically protected internal wiring in high-temperature equipment, which follows directly from the Style’s official Use.
Two conditions in that Use shape most sourcing decisions here. The wiring must not be subjected to repeated flexing, and it must be protected from mechanical abuse. Both are treated as their own sections below rather than as footnotes.
UL 5476 Technical Specifications
| Parameter | Style-level information |
|---|---|
| UL AWM Style | 5476 (UL 758) |
| Description | Single or multiple conductor with other-than-extruded insulation |
| Temperature rating | 450°C |
| Voltage rating | 600 Vac |
| Flame | Horizontal Flame |
| Conductor range | 30 AWG–4/0 AWG |
| Conductor form | Solid or stranded |
| Construction | Mica Tape with Glass Braid |
| 30–12 AWG mica | 17 mil minimum average total mica tape |
| 30–12 AWG glass braid | 7 mil minimum average |
| 11–4 AWG mica | 21 mil minimum average |
| 11–4 AWG glass braid | 15 mil minimum average |
| 3–4/0 AWG mica | 26 mil minimum average |
| 3–4/0 AWG glass braid | 20 mil minimum average |
| Glass braid treatment | Silicone varnish or TFE finish |
| Optional binder | May be applied between mica tape and glass braid according to the qualified construction |
| Optional multi-conductor | Two or more conductors, maximum overall assembly diameter 1.500 inches |
| Optional shield | 36–30 AWG Type “A” nickel or 27 percent minimum nickel coated copper |
| Official Use | Internal wiring where not subjected to repeated flexing and protected from mechanical abuse, and where the acceptability, including current-carrying capacity, has been determined by UL, LLC |
Three Construction Bands Across the Conductor Range
UL 5476 does not apply one identical construction requirement from 30 AWG to 4/0. The minimum average thickness requirements for the mica tape and the treated glass braid change with conductor-size band:
| Conductor size | Min. avg. total mica tape | Min. avg. treated glass braid |
|---|---|---|
| 30–12 AWG | 17 mils | 7 mils |
| 11–4 AWG | 21 mils | 15 mils |
| 3–4/0 AWG | 26 mils | 20 mils |
Identifying which band applies is part of specifying the wire, not an afterthought. An enquiry naming Style 5476 without an AWG has not yet identified which of the three constructions is being asked for.
The 30–12 AWG Band
This band carries a 17 mil minimum average total mica-tape thickness and a 7 mil minimum average treated glass braid.
No claim is made here that this makes the product thin wall, compact in OD, or more flexible than the other bands — those would need construction-specific evidence the Style-level data does not supply. The band is also not a reason to recommend 12 AWG for any particular oven or heater; conductor size comes from the equipment design, and the band follows from it.
The 11–4 AWG Band
From 11 AWG through 4 AWG the requirements increase to 21 mil minimum average total mica tape and 15 mil minimum average treated glass braid.
Greater specified construction thickness in this band does not by itself mean better mechanical protection, higher current capability or greater durability, and none of those are claimed. The AWG and the band simply need to match the engineering requirement.
The 3–4/0 AWG Band
The Style extends into large conductor sizes, and this band carries a 26 mil minimum average total mica tape with a 20 mil minimum average treated glass braid.
No current capacity, motor power, heater power or furnace kW value is assigned to these sizes. What does change commercially at this end of the range is practical: large-conductor enquiries usually turn on dimensional data, termination interface and packaging far more than small-conductor ones do, and those details are worth sending with the first enquiry rather than after a quotation is issued. The dimensions themselves are not published here.
Do Not Sum the Mica and Braid Figures
The mica tape and the treated glass braid are separate construction elements with separate minimum average thickness requirements. 17 and 7 do not combine into a 24 mil finished insulation wall; 21 and 15 do not make 36; 26 and 20 do not make 46. No finished outside diameter is calculated from them.
The correct UL terminology is minimum average total mica tape layers, and minimum average glass braid treated with silicone varnish or TFE finish. These are minimum averages for the elements, not a guaranteed radial wall for any ordered construction.
Mica Tape With Treated Glass Braid
The construction on this page is mica tape with a glass braid treated with silicone varnish or TFE finish. The treatment applies to the braid; it does not make this a silicone-insulated wire, and TFE is not the primary insulation.
Varnish and finish thickness beyond the verified braid figures are not established at Style level and are not invented here. Where the BOM controls the treatment, state which is required so it can be confirmed against the qualified construction.
The 450°C Rating Applies to the Wire
450°C is a verified Style 5476 rating for the wire. It does not establish that a complete oven or furnace chamber may operate continuously at 450°C, that connectors or terminals are rated at that temperature, that accessories are, or that every nearby component may be exposed to it.
The temperature at the wire’s actual routing position, and the ratings of the hardware it terminates into, are separate equipment-design questions.
600 Vac Is an AC Rating
The Style rating is 600 Vac and should be written that way in technical content rather than as a generic “600V.” It should not be restated as 600 Vdc, as a 600V peak value, as an impulse rating or as a dielectric withstand voltage without separate evidence.
Not Subjected to Repeated Flexing
The official Use limits this Style to internal wiring not subjected to repeated flexing. That is a use condition, and it defines what the product is for.
Style 5476 is therefore not offered here as flexible cable, continuous-flex wire, high-flex cable, a moving heater lead, robotic cable or drag-chain wire. Bending a conductor once during equipment assembly is a different thing from repeated movement in service, and installation bending does not make a repeated-flex application. No bend radius or flex-cycle specification is published on this page.
Where the equipment produces repeated movement at the wire’s position, suitability needs review before Style 5476 is assumed to fit. State whether movement occurs when sending the enquiry.
Protected From Mechanical Abuse
The Use also requires protection from mechanical abuse, which places the obligation on the equipment design rather than on the wire.
The treated glass braid is not presented here as making the wire suitable for exposed external routing, uncontrolled abrasion, impact, crushing, sharp-edge contact, open machinery wiring or building wiring. No abrasion or mechanical rating is claimed. Where the routing path crosses a metal edge, a pass-through or a clamped position, the protection method belongs in the equipment design and is worth describing in the enquiry.
Current-Carrying Capacity Is Not Published Here
The official Use states that acceptability, including current-carrying capacity, has been determined. That is a statement about how the Style is evaluated, not an ampacity table, and no such table appears on this page.
No amperes by AWG, heater wattage by conductor size, current recommendation or furnace power recommendation is provided. AWG selection remains an engineering and BOM requirement.
Conductor Material Is Not Defined by This Style Entry
The Style-level information establishes conductor size and solid or stranded form. It does not establish a universal primary-conductor material or plating, so bare copper, tinned copper, nickel-plated copper and nickel conductor are none of them assumed on this page.
One point deserves emphasis because it is a common misreading. The Style’s nickel and nickel-coated-copper wording — 36–30 AWG Type “A” nickel or 27 percent minimum nickel coated copper — belongs to the optional shield construction, not to the primary conductor. It should never be quoted as the conductor specification. Where conductor material or finish matters to the BOM, make it an explicit RFQ field.
Optional Binder
The Style permits an optional binder applied between the mica tape and the glass braid, according to the qualified construction, with the material detail referred to the applicable construction record. The material is not specified here. Treat it as a construction-confirmation field where the drawing controls it.
Optional Multi-Conductor Assembly
Two or more qualified conductors may be cabled together with a maximum overall diameter of 1.500 inches. A mica-glass binder and/or fiberglass fillers may be employed, and the assembly may have an overall treated glass braid.
This is an option within the Style, not a description of every Style 5476 product. State single-conductor or multi-conductor explicitly in the enquiry.
Optional Shield
The optional shield uses 36–30 AWG Type “A” nickel or 27 percent minimum nickel coated copper. It is a distinct construction field, separate from the primary conductor, separate from the treated glass braid over the mica tape, and separate from any overall braid on a multi-conductor assembly.
No performance is attributed to it here. EMI performance, RFI attenuation, grounding performance, abrasion protection and corrosion performance are not established by the Style-level information and would require separate verification for a specific construction. Where a shield is required, state yes or no and supply the controlling specification.
Finished OD and Dimensional Fit
Finished outside diameter is not calculated here from the mica and glass-braid thickness values, and the Style-level information does not establish one universal OD for any conductor size.
Where dimensional fit matters, request conductor AWG, nominal OD, maximum OD, tolerance, the routing opening, ceramic sleeve or feedthrough dimensions, and the terminal interface, taken from the approved construction.
Termination Requirements
The Style does not establish a terminal type, lug type, crimp size, strip length, connector, ceramic terminal block or sleeve, and none are invented here. Where prepared leads are required, supply the termination drawing or part number. This matters most in the 3–4/0 range, where getting the termination interface right before quotation avoids reworking both the lead and the hardware around it.
Official AWM Use Boundary
The official Use for Style 5476 is: Internal wiring where not subjected to repeated flexing and protected from mechanical abuse, and where the acceptability, including current-carrying capacity, has been determined by UL, LLC.
Fixed internal wiring sections of industrial ovens, furnaces, kilns, thermal-processing equipment and heating equipment are buyer application contexts in which an appropriate Style 5476 construction may be evaluated when those Use conditions are satisfied. They are not separately UL-approved applications, and none is described that way here.
What UL 5476 Does Not Automatically Define
- Primary conductor material and conductor plating
- Strand count, strand diameter and conductor resistance
- Ampacity
- Finished OD and OD tolerance
- Bend radius and flex-cycle life
- Termination type and connector compatibility
- Abrasion rating
- Stock status, reel length, MOQ and production lead time
Common RFQ Mismatches
- Style 5476 specified, AWG omitted. Three construction bands sit inside the 30 AWG–4/0 range.
- “600V” written without distinguishing AC. The Style rating is 600 Vac.
- Same mica and braid thickness assumed across all sizes. The requirements change by band.
- Mica plus braid thickness treated as finished OD. Separate minimum averages, not a dimension.
- Repeated flexing expected. The Use excludes it.
- Mechanical protection not specified. The Use requires it from the equipment design.
- Optional nickel shield read as the conductor specification. Two different construction fields.
- Finished OD omitted where routing is constrained. Fit cannot be confirmed without it.
- Terminal information omitted on large conductors. Most costly in the 3–4/0 band.
- Every 450°C component assumed identically rated. The wire rating is not the assembly rating.
Each of these leaves the enquiry matching more than one construction, or matching one the Use conditions do not support. Both surface later as approval problems rather than quotation problems.
RFQ Checklist
- UL AWM Style 5476
- Conductor AWG; solid or stranded
- Conductor material / plating, if controlled
- 450°C requirement
- 600 Vac requirement
- Applicable AWG construction band
- Optional binder required
- Single-conductor or multi-conductor
- Optional shield required
- Nominal / maximum finished OD, if controlled
- Wire identification requirement
- Fixed routing location
- Repeated movement present: yes / no
- Mechanical-protection method
- Terminal / connector specification
- Cut length or reel requirement
- Quantity, packaging and destination
- Documentation requirements
- Actual high-temperature equipment application
Applicable RoHS / REACH documentation can be confirmed according to the ordered construction. UL marking is applied according to the confirmed ordered construction, and material is supplied as UL-recognized component wire under qualified manufacturing scope.
