UL 3239 High Voltage Silicone Wire — Up to 200°C / Up to 60,000V DC / 24–10 AWG
UL AWM Style 3239 is a high-voltage DC wire specification rated up to 200°C and up to 60,000V DC under UL Subject 758. The voltage rating and insulation construction of each UL 3239 product are construction-dependent — thicker insulation walls produce higher DC voltage ratings. The permitted use is internal wiring of TV receivers, or other applications where acceptability has been determined by UL.
UL 3239 is a framework specification: the specific temperature rating, voltage rating, insulation material, and wall thickness for each product are confirmed against the UL 3239 standard at the time of production. Common voltage grades available include 10kV, 20kV, 30kV, 40kV, 50kV, and 60kV DC — availability and construction details are confirmed at enquiry stage. For high-temperature DC applications up to 250°C at 50,000V, see UL 1911. For 10,000V AC ignition wire, see UL 3304.
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Technical Specifications — UL AWM Style 3239
| Parameter | Specification |
|---|---|
| UL AWM Style | 3239 |
| UL Subject | 758, Section 3 |
| Maximum Temperature | 200°C (actual rating depends on insulation construction) |
| Maximum Voltage | 60,000V DC (actual rating depends on insulation construction) |
| Conductor Range | 24–10 AWG copper or nickel; 12–10 AWG aluminium (90°C max); 27–20 AWG resistance wire |
| Insulation Type | Extruded or non-extruded thermoplastic and/or thermosetting — per facing page construction |
| Conductor Plating | Tinned, silver-plated, nickel-plated, heat-bonded, or overcoated (copper) |
| Optional Shield | Optional — per facing page |
| Optional Covering / Jacket | Optional — per facing page |
| Flame Rating | Horizontal flame and VW-1 |
| UL Recognition | UL Recognized Component — file on record |
| Permitted Use | Internal wiring of TV receivers, or where acceptability has been determined by UL |
| RoHS / REACH | Documentation available on request |
Voltage Grade Reference — Construction-Dependent
The DC voltage rating of UL 3239 is determined by the insulation wall thickness of the specific product construction. The table below shows typical product constructions available — actual dimensions and availability are confirmed at enquiry stage.
| Voltage Grade (DC) | AWG Range | Insulation Thickness (mm) | Approx. OD (mm) |
|---|---|---|---|
| 10kV DC | 24–10 AWG | 0.95–1.20 | 2.50–5.50 |
| 20kV DC | 22–14 AWG | 1.65–1.90 | 4.00–6.20 |
| 30kV DC | 22–16 AWG | 2.15–2.45 | 5.10–7.50 |
| 40kV DC | 20–18 AWG | 2.60–2.85 | 6.50–8.20 |
| 50kV DC | 20–18 AWG | 3.10–3.40 | 7.80–9.50 |
| 60kV DC | Confirm at enquiry | Confirm at enquiry | Confirm at enquiry |
Voltage grade, AWG, conductor plating, and optional shield or jacket must be specified at enquiry. Confirm your required DC voltage rating, conductor size, and application before ordering — not all voltage grades are available in all AWG sizes.
Typical Application Contexts
UL 3239’s permitted use is internal wiring of TV receivers, or other applications where acceptability has been determined by UL. In practice, equipment applications where UL acceptability is commonly established include:
- Internal high-voltage DC wiring in DC power supply enclosures — from rectifier and multiplier stages to output terminals
- Internal wiring in electrostatic precipitator power supplies and corona discharge equipment
- Internal HV DC lead connections in display and imaging equipment internal wiring sections
- Other high-voltage DC internal wiring applications where equipment acceptability has been determined by UL — confirm with your equipment’s UL listing requirements before specifying
UL 3239 is not intended for external wiring, field wiring, or open routing. The wire must be used in a protected internal wiring context within equipment where UL acceptability has been established.
UL 3239 vs UL 1911 — High Voltage DC Selection Reference
| Parameter | UL 3239 | UL 1911 |
|---|---|---|
| Max voltage | 60,000V DC | 50,000V DC |
| Max temperature | 200°C | 250°C |
| AWG range | 24–10 AWG (Cu/Ni) | 24–10 AWG |
| Insulation | Extruded or non-extruded — per facing page | Any material — per facing page |
| Permitted use | TV receivers; other uses where acceptability determined by UL | Internal wiring of electronic gas ignitor systems |
Ordering Information
UL 3239 is a custom-specification product. Specify required DC voltage rating, AWG size, conductor material (copper / nickel), conductor plating (tinned / silver / nickel), optional shield or jacket, insulation colour, quantity, and destination port. Confirm availability and lead time at enquiry stage. Response within 12 hours.






