Detailed Description
- q: "What certifications are available?"
- q: "Can I order custom colors, lengths, or processed ends?"
a: "Custom colors are listed, and processing options include cut-to-length, stripping, tinning, spooling, and anti-tangle winding. Share your drawing or sample for confirmation."
UL3239 silicone high voltage wire is a single-conductor, stranded hookup wire built with a tinned copper conductor and silicone rubber insulation. It is rated 3000 V DC (3 kV DC) and -60 °C to +200 °C, with a size range from 32 AWG to 8 AWG. The construction is intended for equipment leads where a standard low-voltage lead would not provide enough dielectric margin or heat resistance.
What Is UL3239 Silicone High Voltage Wire?
UL3239 is a UL AWM silicone high voltage hookup wire used as a lead inside appliances, luminaires, electronic devices, sensors, and instruments. Its core purpose is to carry a single conductor through areas where heat, low temperature, or a 3000 V DC insulation requirement makes ordinary PVC hookup wire unsuitable.
The wire is not a multi-core control cable. It is a single-conductor lead, which makes it useful for point-to-point connection inside equipment, for temperature sensor leads, and for motor or heating element leads where only one conductor is needed. The silicone rubber insulation remains flexible, so the wire can be routed around small components and bent during assembly.
Construction: Tinned Copper Conductor and Silicone Rubber Insulation
Tinned stranded copper conductor
The conductor is made from RoHS tinned stranded copper, also described as tinned oxygen-free copper. The stranding is visible in the specification tables: for example, 32 AWG uses 7/0.12TS in the main table, while larger sizes move to 11/0.16TS, 20/0.18TS, 50/0.18TS, and up to 165/0.25TS for 8 AWG. Tinning helps the copper resist oxidation and keeps the surface bright for soldering or termination.
Silicone rubber insulation
The insulation is RoHS silicone rubber. It provides the -60 °C to +200 °C temperature range and the 3000 V DC voltage rating. The main table lists average and minimum insulation thickness by size, and the outer diameter tolerance is given as ±0.1 mm overall, with ±0.10 / ±0.15 / ±0.20 mm shown by size in the main table.
Colors and printing
Available colors include red, black, white, yellow, blue, green, brown, gray, pink, orange, purple, transparent, yellow/green, and yellow with green stripe. The surface can carry clear printed numbers for identification. The wire is supplied in full rolls, and processing such as cut-to-length, stripping, tinning, spooling, and anti-tangle winding is available.
Electrical and Environmental Ratings
The table below is the main specification table for UL3239 silicone high voltage wire. It covers stranding, insulation wall, finished outer diameter, conductor resistance, current, and packaging from 32 AWG to 8 AWG.
| AWG | Stranding (NO./mm) ±0.01 | Stranded Copper OD mm | Average Thickness mm | Minimum Thickness mm | Finished OD mm | Conductor Resistance Ω/km @ 20 °C | Current | Packaging (m/roll) |
|---|---|---|---|---|---|---|---|---|
| 32AWG | 7/0.12TS | 0.38 | 0.3 | 0.25 | 0.8±0.10 | 250 | 0.8A | 610 |
| 30AWG | 7/0.10TS | 0.3 | 0.35 | 0.28 | 1.0±0.10 | 381 | 0.5A | 610 |
| 28AWG | 7/0.12TS | 0.38 | 0.5 | 0.4 | 1.37±0.10 | 250 | 0.8A | 305 |
| 26AWG | 7/0.15TS | 0.48 | 0.5 | 0.4 | 1.5±0.10 | 165 | 1.2A | 305 |
| 24AWG | 11/0.16TS | 0.61 | 0.5 | 0.4 | 1.6±0.10 | 94.2 | 2A | 305 |
| 22AWG | 12/0.18TS | 0.72 | 0.5 | 0.4 | 1.76±0.10 | 65 | 3A | 305 |
| 20AWG | 20/0.18TS | 0.93 | 0.5 | 0.4 | 1.91±0.10 | 40 | 5A | 305 |
| 18AWG | 30/0.18TS | 1.14 | 0.5 | 0.4 | 2.17±0.10 | 26 | 7A | 305 |
| 16AWG | 50/0.18TS | 1.47 | 0.5 | 0.4 | 2.5±0.10 | 16 | 12A | 305 |
| 14AWG | 41/0.25TS | 1.88 | 0.5 | 0.4 | 3.0±0.10 | 10 | 20A | 305 |
| 12AWG | 65/0.25TS | 2.37 | 0.5 | 0.4 | 3.5±0.10 | 6.5 | 30A | 100 |
| 10AWG | 105/0.25TS | 3.4 | 0.5 | 0.4 | 4.5±0.15 | 3.8 | 50A | 100 |
| 8AWG | 165/0.25TS | 4.39 | 0.5 | 0.4 | 5.5±0.2 | 2.4 | 80A | 100 |
Notes: Values are quoted as given in the supplier's specification tables.
The insulation resistance is 100 MΩ/km @ 20 °C. The 3 kV construction is tested at 3000 V. For the multi-voltage constructions listed below, the test voltage range is 6000–25000 V. These ratings matter when the lead is used near a high voltage power supply or when leakage current must be limited in a sensor circuit.
Multi-Voltage Constructions: 3000 V, 6000 V, 10000 V, and 20000 V
The 3000 V DC rating is the standard voltage rating for this UL3239 wire. The same silicone high voltage wire family can also be supplied in 6000 V, 10000 V, and 20000 V constructions. As the voltage grade rises, the insulation wall becomes thicker and the finished outer diameter increases. The table below gives the thickness and finished OD for each voltage grade from 28 AWG to 16 AWG.
| AWG | Conductor Construction | Diameter mm | 3000 V Thickness / Finished OD mm | 6000 V Thickness / Finished OD mm | 10000 V Thickness / Finished OD mm | 20000 V Thickness / Finished OD mm | Packaging m/roll |
|---|---|---|---|---|---|---|---|
| 28 | 7×0.12 | 0.37 | 0.50 / 1.37 | 0.70 / 1.77 | 1.00 / 2.37 | 1.30 / 2.97 | 305 |
| 26 | 7×0.15 | 0.49 | 0.50 / 1.49 | 0.70 / 1.89 | 1.00 / 2.49 | 1.30 / 3.09 | 305 |
| 24 | 11×0.16 | 0.61 | 0.50 / 1.61 | 0.70 / 2.01 | 1.00 / 2.61 | 1.30 / 3.21 | 305 |
| 22 | 12×0.18 | 0.74 | 0.50 / 1.74 | 0.70 / 2.14 | 1.00 / 2.74 | 1.30 / 3.34 | 305 |
| 20 | 20×0.18 | 0.95 | 0.50 / 1.95 | 0.70 / 2.35 | 1.00 / 2.95 | 1.30 / 3.55 | 305 |
| 18 | 30×0.18 | 1.14 | 0.50 / 2.14 | 0.70 / 2.54 | 1.00 / 3.14 | 1.30 / 3.74 | 305 |
| 16 | 50×0.18 | 1.47 | 0.50 / 2.47 | 0.70 / 2.87 | 1.00 / 3.47 | 1.30 / 4.07 | 305 |
Notes: Values are quoted as given in the supplier's specification tables.
For a 3000 V DC application, the 3000 V construction is usually the starting point. If the working voltage, transient level, or clearance requirement is higher, move to the 6000 V, 10000 V, or 20000 V construction and accept the larger outside diameter. This is the main selection decision on a silicone rubber insulated high voltage lead.
AWG, Current, and OD Reference Data
Two additional reference tables help when comparing AWG, copper cross-section, current, and total outer diameter. They are quoted separately because they come from different specification tables.
Copper count and current reference
| AWG | mm² | Copper Strands × Strand OD mm | Current A |
|---|---|---|---|
| 30AWG | 0.05 | — | 0.4 |
| 28AWG | 0.09 | — | 0.7 |
| 26AWG | 0.14 | 11 × 0.161 | 1.14 |
| 24AWG | 0.22 | 12 × 0.161 | 1.79 |
| 22AWG | 0.31 | 20 × 0.181 | 2.47 |
| 20AWG | 0.51 | 30 × 0.181 | 4.12 |
| 18AWG | 0.77 | 50 × 0.181 | 6.18 |
| 16AWG | 1.29 | — | 10.29 |
| 14AWG | 2.08 | 41 × 0.254 | 16.62 |
| 12AWG | 3.29 | 65 × 0.254 | 26.35 |
| 10AWG | 5.32 | 105 × 0.254 | 42.56 |
| 8AWG | 8.36 | 165 × 0.254 | 66.89 |
Notes: Values are quoted as given in the supplier's specification tables.
Conductor structure and total OD reference
| AWG | Conductor Construction | Total OD mm | mm² | Temperature Rating °C |
|---|---|---|---|---|
| 32AWG | 7/0.10ts | 0.8 | 0.06 | 200 |
| 30AWG | 7/0.10ts | 1.0 | 0.06 | 200 |
| 28AWG | 7/0.12ts | 1.37 | 0.08 | 200 |
| 26AWG | 7/0.15ts | 1.5 | 0.12 | 200 |
| 24AWG | 11/0.16ts | 1.6 | 0.22 | 200 |
| 22AWG | 12/0.18ts | 1.76 | 0.3 | 200 |
| 20AWG | 20/0.18ts | 1.9 | 0.5 | 200 |
| 18AWG | 30/0.18ts | 2.17 | 0.76 | 200 |
| 16AWG | 50/0.18ts | 2.5 | 1.3 | 200 |
Notes: Values are quoted as given in the supplier's specification tables.
Applications, Selection, and Custom Supply
UL3239 silicone high voltage wire is used in appliance lead wire, luminaire wiring, electronic device leads, temperature sensor leads, LED luminaires, circuit boards, integrated panels, motor lead wire, electric tools, industrial machinery, lithium battery packs, model hobby battery leads, medical equipment, audio equipment, instrumentation, and electric heating appliances. In each case, the common requirement is a single flexible conductor that can operate from -60 °C to +200 °C and provide 3000 V DC insulation.
For selection, start with the current column in the main table and choose an AWG that covers the expected load. Then choose the voltage construction. A 3 kV DC silicone insulated wire is the standard UL3239 rating; 6 kV, 10 kV, and 20 kV constructions are available when the insulation wall and finished OD can be larger. Check the finished OD against your connector, grommet, and routing space.
For installation, the silicone insulation is flexible and can be bent during assembly, but stripping and termination should be done with tooling that does not nick the conductor or cut into the insulation. Confirm your stripping length and terminal type with your harness process. The wire can be supplied cut to length, stripped, tinned, spooled, or wound to reduce tangling.
Certification is UL and RoHS. The supplied documents do not include a UL file number, so no E-number is quoted. If your equipment file requires the exact UL file number, ask for it before approval. Available colors, packaging, and processing options can be customized; packaging is 610 m/roll for 32–30 AWG, 305 m/roll for 28–14 AWG, and 100 m/roll for 12–8 AWG.
If your equipment needs a 200 °C high voltage hookup wire with a small, flexible silicone lead, this UL3239 construction is a direct candidate. Send the required AWG, voltage grade, color, length, and processing through the inquiry form, and confirm the construction before order.