UL 5335 450°C 600V Mica Wire for Protected Internal Wiring
UL AWM Style 5335 is a single or multiple conductor with non-extruded insulation, rated 450°C and 600 Vac with a Horizontal flame classification. Its insulation is mica with glass braid, the braid treated with silicone varnish or TFE finish, and it covers conductor sizes from 22 AWG to 4/0 AWG. The Style’s Use is “Internal Wiring where protected from mechanical abuse.” In short, UL 5335 is a 450°C-rated mica and glass-braid AWM construction for protected internal wiring.
This page covers the Style as a wire: its conductor range and forms, the mica and glass-braid thickness groups, the braid treatments, the optional shield materials and the Use boundary. For the broader Style overview, see the UL 5335 Mica Wire category.
Verified UL 5335 Technical Specifications
| Parameter | UL AWM Style 5335 record |
|---|---|
| Style | 5335 |
| Description | Single or multiple conductor with non-extruded insulation |
| Temperature | 450°C |
| Voltage | 600 Vac |
| Flame | Horizontal flame |
| Conductor range | 22 AWG – 4/0 AWG |
| Conductor form | Solid or stranded in sizes 22 – 8 AWG; larger sizes stranded only |
| Insulation | Mica with Glass Braid |
| Mica, min avg thickness | 22 – 12 AWG: 23 mils; 11 – 4 AWG: 27 mils; 2 – 4/0 AWG: 32 mils |
| Glass braid, min avg thickness | 22 – 12 AWG: 5 mils; 11 – 4 AWG: 10 mils; 3 – 4/0 AWG: 15 mils |
| Braid treatment | Silicone varnish or TFE finish |
| Optional shield | Nos. 36 – 30 AWG Type “A” Nickel, or 27% minimum nickel coated copper, or nickel-chromium-iron, or stainless steel 304 |
| Optional assembly | Two or more conductors cabled together, max O.D. 1.500 inches; mica glass binder and/or fiberglass fillers; overall treated glass braid |
| Marking | General |
| Use | Internal Wiring where protected from mechanical abuse |
Four points in this table need clarification. First, all thickness values are minimum averages; the record states no minimum-at-any-point value. Second, the mica and glass-braid tables use different size boundaries for their heaviest group (2 – 4/0 AWG for mica, 3 – 4/0 AWG for braid), explained below. Third, the shield materials are options for the shield only, not for the primary conductor. Fourth, the record does not state the primary conductor material or plating; these are confirmed according to the qualified ordered construction.
22 AWG–4/0 AWG Conductor Range
The conductor field reads: “22 AWG – 4/0 AWG. Solid or stranded in sizes 22-8 AWG; larger sizes stranded only.” The range therefore has two parts:
- 22 AWG through 8 AWG: solid or stranded.
- Larger than 8 AWG (6 AWG through 4/0 AWG): stranded only. A solid conductor is not a permitted Style 5335 construction at these sizes.
The record does not define the primary conductor’s material or plating, strand count, strand diameter, conductor class, lay length or resistance, and it assigns no current rating to any size. Larger sizes are not described here as high-power, and no current figure is derived from AWG or general wiring-code tables. These details are confirmed according to the qualified ordered construction.
Mica and Glass Braid Construction by AWG Group
The insulation is described as “Mica with Glass Braid,” with separate minimum-average thickness requirements for the mica and for the treated glass braid:
| Layer | Conductor size | Minimum average thickness |
|---|---|---|
| Mica | 22 – 12 AWG | 23 mils (0.58 mm) |
| Mica | 11 – 4 AWG | 27 mils (0.69 mm) |
| Mica | 2 – 4/0 AWG | 32 mils (0.81 mm) |
| Glass braid, treated | 22 – 12 AWG | 5 mils (0.13 mm) |
| Glass braid, treated | 11 – 4 AWG | 10 mils (0.25 mm) |
| Glass braid, treated | 3 – 4/0 AWG | 15 mils (0.38 mm) |
Four points in this table need clarification. First, the millimetre values are arithmetic conversions (1 mil = 0.0254 mm), not separate UL specifications. Second, every value is a minimum average; none is nominal, typical, exact or a minimum at any point, and no tolerance is attached. Third, the heaviest mica group begins at 2 AWG while the heaviest braid group begins at 3 AWG; 3 AWG appears in the braid table but not in the mica table, so its mica requirement is not assigned to a neighbouring group and must be confirmed against the applicable qualified construction. Fourth, the layer values are separate requirements and are not combined into a finished wall or used to derive finished outside diameter.
The record names the material “Mica.” It is not described as composite mica glass, mineral-insulated cable or MI cable, and no mica type or grade is identified. The record also gives no dielectric-strength value, and none is inferred from these thicknesses.
Silicone Varnish or TFE Finish on the Glass Braid
The braid is described as “Glass braid treated with silicone varnish or TFE finish.” Both treatments are permitted. The Style does not tie either one to a temperature or application, and it does not rank them for abrasion, flexibility, dielectric, chemical or life performance. They are finishes on the glass braid, not primary insulation: silicone varnish is not silicone rubber insulation, and TFE finish is not PTFE insulation. Where a drawing requires one treatment, it is confirmed for the ordered construction.
450°C / 600 Vac / Horizontal Flame Rating
The rating field reads “450 deg C, 600 Vac, Horizontal flame.” 450°C is the rated temperature; the record does not describe it as continuous, sustained or long-term. 600 Vac is the voltage rating; no DC value is stated.
The 600 Vac rating is a property of the Style, not a rule for choosing it. Whether Style 5335 suits a particular circuit or equipment depends on the actual design, construction and applicable evaluation requirements; this page does not set voltage thresholds for selecting it over other Styles, and a voltage rating does not indicate a power level.
Horizontal flame is the flame classification. VW-1, FT1, FT2, vertical flame and IEC flame classes are not Style-wide properties of UL 5335.
Protected Internal Wiring Application
The Use of Style 5335 reads: “Internal Wiring where protected from mechanical abuse.” It has two parts, and both control how the wire is applied:
- Internal wiring: the wire is for wiring within equipment. The Use does not name equipment types, and no named-equipment list is added here.
- Protected from mechanical abuse: the routing must be protected. Exposed mechanical routing, field, building, tray, branch-circuit, outdoor, direct-burial, service and welding cable use fall outside the Use. Neither the optional shield nor an overall assembly braid removes this requirement.
The Use does not contain a repeated-flexing clause, and none is added here. Equally, no flex rating is established; UL 5335 is not described as high-flex, continuous-flex or drag-chain wire.
When specifying protected internal wiring with this Style, the buyer’s routing description and protection conditions are part of the information needed to confirm the construction.
Optional Shield Constructions
The Shield entry reads: “(Optional) Nos. 36-30 AWG Type “A” Nickel or 27% minimum nickel coated copper or nickel-chromium-iron or stainless steel, 304.” The shield is optional and, where used, is made of 36–30 AWG strands of one of four listed materials:
- Type “A” Nickel
- 27% minimum nickel coated copper
- nickel-chromium-iron
- stainless steel 304
These are shield materials only. They do not indicate the material of the primary conductor, which the record does not specify. The record also does not establish shield coverage, EMI attenuation, shielding effectiveness, transfer impedance, abrasion, crush, corrosion or thermal performance, and no shield material is recommended over another here. If a shield is required, the material is set by the customer’s specification and confirmed for the ordered construction.
Multiple-Conductor Construction Available Within Style 5335
The Style also permits an assembly: “Two or more conductors described above, may be cabled together with a max O.D. of 1.500 inches. A mica glass binder and/or fiberglass fillers may be employed. The assembly has an overall treated glass braid.” The Style defines no fixed core counts, and no assembly diameter is estimated here. Buyers who need that construction can find it on the dedicated UL 5335 Multi-Core Mica Glass Braid Cable page.
What Style 5335 Does and Does Not Define
The Style record defines the rating (450°C, 600 Vac, Horizontal flame); the conductor range and forms; the mica and treated-glass-braid minimum averages by size group; the braid treatments; the optional shield materials and strand sizes; the optional multiple-conductor assembly; the marking field (General); and the Use.
The Style record does not define:
- primary conductor material, plating or strand construction
- conductor resistance or current rating
- a mica thickness for 3 AWG
- minimum-at-any-point thicknesses
- finished outside diameter or tolerance
- shield coverage or shielding performance
- termination hardware or methods
- a flex rating, bend radius or service life
Common Procurement Errors
- Specifying a solid conductor above 8 AWG.
- Assigning 3 AWG to a neighbouring mica group without confirmation.
- Treating mica or braid values as nominal or point minimums.
- Reading a shield material as the conductor material.
- Attributing EMI or mechanical performance to the optional shield.
- Treating 600 Vac as a selection rule or as a power level.
- Assigning a current rating by AWG.
- Specifying the wire for routing exposed to mechanical abuse.
- Describing the rating as continuous or adding a DC value.
How to Specify UL 5335 Mica Wire for Protected Internal Wiring in an RFQ
The Style fixes the rating, conductor range and forms, the thickness schedule, the braid treatments, the shield and assembly options and the Use. The following should be stated by the buyer and confirmed for the ordered qualified construction, not filled with assumed values:
- required AWG size
- solid or stranded requirement, where permitted
- conductor material and plating requirement
- detailed stranding requirement, if controlled
- mica and glass-braid construction requirement
- silicone varnish or TFE finish requirement, if controlled
- single-conductor or multiple-conductor requirement
- conductor count, if multiple-conductor construction is required
- optional binder requirement
- optional fiberglass fillers requirement
- optional shield requirement
- shield material, if required
- finished OD or tolerance, if controlled
- marking requirement
- quantity
- packaging
- documentation requirement
- equipment and internal routing description
- mechanical-protection conditions
UL Marking and Documentation
Style 5335 wire is supplied as UL-recognized component wire where supplied under qualified manufacturing scope. The marking field of the Style record reads “General”; it does not prescribe a fixed legend, and identical marking is not assumed for every construction. UL marking is applied according to the confirmed ordered construction and should be confirmed at the order stage.
Applicable RoHS / REACH documentation can be confirmed according to the ordered construction. CE, UKCA, CSA, FT1, VW-1, CPR, VDE, DIN, EN and IEC are not declared for this product.
Commercial, origin, compliance and transport documents are identified during quotation and confirmed according to the order.
