UL 3573 Silicone Ignition Wire — 10,000V / 200°C Triple-Layer AWM
Inner Silicone + Fiberglass Braid + Outer Insulation for High-Voltage Ignition Leads
UL Style 3573 is a single-conductor appliance wiring material (AWM) built with a triple-layer construction: an inner extruded silicone rubber insulation, a fiberglass braid or serve, and an outer insulation layer applied over the braid. Rated for 200°C continuous operation at 10,000V AC with a horizontal-flame rating, the style covers conductor sizes from 22 AWG to 12 AWG in solid or stranded round construction. This architecture is designed specifically for electronic ignition and similar high-voltage spark applications in gas ranges and fuel-oil burner systems, where the wire must be protected from damage during handling, installation, and servicing of the appliance. CableApex supplies UL 3573 wire as a UL Recognized Component — file on record — meeting the full dimensional and performance requirements of UL 758 AWM.
UL 3573 Specification Summary
- Style Number: UL 3573 (AWM, UL 758)
- Temperature Rating: 200°C continuous
- Voltage Rating: 10,000V AC
- Flame Rating: Horizontal flame
- Conductor Range: 22 AWG – 12 AWG, solid or stranded round
- Inner Insulation: Extruded SR-silicone, 30 mils average / 27 mils min at any point
- Braid: Fiberglass braid or serve
- Outer Insulation: Over braid, 10 mils minimum at any point
- Conductor Options: Bare or tinned copper
- UL Status: UL Recognized Component — file on record
- Intended Use: Electronic ignition or similar application in gas ranges or gas / fuel-oil burner systems, where protected from damage
Conductor & Dimension Reference
UL 3573 covers 22 AWG through 12 AWG — the gauge range specified for ignition transformer output leads and flame-sensor wiring. AWG is the primary sizing reference, with metric cross-section shown for convenience.
| Gauge (AWG) | Cross-Section (mm²) | Stranding | Nom. OD (mm) | Max. Resistance (Ω/km) |
|---|---|---|---|---|
| 22 AWG | 0.33 | 7/0.25 | 3.00 | 57.6 |
| 20 AWG | 0.52 | 10/0.25 | 3.20 | 36.4 |
| 18 AWG | 0.82 | 16/0.25 | 3.40 | 23.2 |
| 16 AWG | 1.31 | 26/0.25 | 3.70 | 14.6 |
| 14 AWG | 2.08 | 41/0.25 | 4.00 | 8.96 |
| 12 AWG | 3.31 | 65/0.25 | 4.40 | 5.64 |
Typical Application Environments
The 10,000V dielectric rating combined with the triple-layer construction defines UL 3573 as a purpose-built ignition lead — not a general-purpose high-temperature hook-up wire. Its intended environments are narrow but critical:
- Gas range electronic igniters: The spark ignition module in a gas range produces a high-voltage pulse that must travel from the ignition transformer to the burner electrode without flashover or insulation breakdown. UL 3573’s inner silicone withstands the 200°C proximity to the burner, the braid resists abrasion from sliding oven racks and door mechanisms, and the outer insulation seals the braid against moisture and grease ingress.
- Fuel-oil burner ignition systems: Commercial and residential oil-fired furnaces and boilers use a high-voltage arc between electrodes to ignite atomised fuel. The ignition lead operates inside the blast tube, exposed to radiant heat from the combustion chamber and hydrocarbon residue. The triple-layer build provides combined thermal, mechanical, and chemical protection in a single wire.
- Industrial gas-fired heating equipment: Large process burners, commercial deep fryers, heated dip tanks, and industrial dryers with pilot ignition systems require a protected 10kV lead capable of surviving thousands of ignition cycles without degradation.
- Oven and range sensor wiring: Flame-sensing and thermocouple leads routed through the heated cavity alongside ignition leads can share the same 200°C / 10kV-rated construction for wiring simplification.
UL 3573 vs UL 3304 — Two 10kV Ignition Wire Constructions Compared
Buyers specifying a 10kV ignition lead for gas or fuel-oil systems will encounter both UL 3573 and UL 3304. The two styles share the same voltage, temperature, gauge range, and intended use, but differ in construction philosophy:
| UL Style | Construction | Temp | Voltage | Key Characteristic |
|---|---|---|---|---|
| 3573 (this page) | SR 30 mil + braid + outer insulation 10 mil | 200°C | 10,000V | Triple-layer: sealed outer insulation over braid prevents moisture and grease ingress |
| 3304 | SR 40 mil + fiberglass braid (no outer insulation) | 200°C | 10,000V | Thicker single silicone layer; open braid surface — simpler construction, lower cost |
| 3135 | SR 30 mil (no braid, no outer insulation) | 200°C | 600V | General-purpose 200°C silicone; not rated for ignition-class voltage |
| 1911 | Various (see facing page) | 250°C | 50,000V DC | Ultra-high-voltage DC ignition for electronic gas ignitor systems; 5× the voltage of 3573 |
UL Recognition
All UL 3573 wire supplied by CableApex is produced under active UL Follow-Up Service as a UL Recognized Component — file on record. Each production reel carries the UL Recognized Component mark in accordance with UL Subject 758 marking requirements. Full recognition documentation is available on request for purchasing, compliance, or import customs purposes.
Related UL Styles for Comparison
- UL 3304 Silicone Ignition Wire — 10,000V / 200°C with Fiberglass Braid
- UL 1911 High-Voltage Ignition Wire — 50,000V DC / 250°C
- UL 3135 Silicone Wire — 200°C / 600V Totally Enclosed
- All AWM Wire Styles
Order Information
Minimum order quantity is 100 metres per colour per gauge. Quotations are returned within 12 hours of enquiry. Please indicate AWG size, conductor finish (bare or tinned), quantity, colour, and preferred delivery port in the form below.
