Approx LBS/MFT10.00, 11
AWG Size18
Cond. MaterialTinned Copper
Conductor Stranding16/30
Copper LBS/MFT5
CSA TypeCSA C22.2 No. 38 FT-1 & FT-2
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
SIS Wire
SIS wire is designed for use in dry locations to wire electrical switchgear, control panels, substations, and related equipment. This type of wire features cross-linked polyethylene (XLPE) insulation and stranded tinned copper conductors for flexibility and long-term durability.
Per NEC specifications, SIS wire is available in sizes from 14 AWG up to 4/0 AWG, with a maximum temperature rating of 90°C. Wires between 18 AWG and 14 AWG are typically marked as “Suitable for switchboard use.”
Browse our inventory of SIS wire in multiple sizes and colors—available online and ready to ship today.
30 items
Approx LBS/MFT256.00
AWG Size18
Cond. MaterialTinned Copper
Conductor Strandingsolid
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
No. of Cond.1
No. of Strands1
Approx LBS/MFT0.00
AWG Size18
Cond. MaterialTinned Copper
Conductor Stranding7/26
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
No. of Cond.1
No. of Strands7
Approx LBS/MFT0.00
AWG Size16
Cond. MaterialTinned Copper
Conductor Strandingsolid
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
No. of Cond.1
No. of Strands1
Approx LBS/MFT13, 13.00
AWG Size16
Cond. MaterialTinned Copper
Conductor Stranding26/30
Copper LBS/MFT8.0
CSA TypeCSA C22.2 No. 38 FT-1 & FT-2
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
Approx LBS/MFT0.00
AWG Size16
Cond. MaterialTinned Copper
Conductor Stranding7/24
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
No. of Cond.1
No. of Strands7
Approx LBS/MFT20, 20.00
AWG Size14
Cond. MaterialTinned Copper
Conductor Stranding41/30
Copper LBS/MFT12.5
CSA TypeCSA C22.2 No. 38 FT-1 & FT-2, SIS/CL1251
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
Approx LBS/MFT0.00
AWG Size14
Cond. MaterialTinned Copper
Conductor Strandingsolid
CSA TypeSIS/CL1251
Insul. MaterialCross-Linked Polyethylene (XLPE)
Max. Temp90C
No. of Cond.1
Additional Information
What is SIS Wire?
The term SIS wire refers to a range of single-core conductors with cross-linked polyethylene (XLPE) insulation, intended for use in electrical switchboards and panels with voltages up to 600v. NEC Table 310.104(A) defines type SIS as switchgear and switchboard wire with flame-retardant thermoset insulation suitable for continuous operation at temperatures up to 90°C. These constructions are dual-rated under several UL standards and comply with CSA SIS and CL1251 types.
What are the Intended Applications of SIS Wire?
SIS wire is designed exclusively for dry locations, where it is used to wire electrical switchgear, control panels, substations, and associated equipment. NEC categorizes SIS conductors from 14 AWG to 4/0 AWG with a maximum operating temperature of 90°C. Because 14 AWG is the smallest recognized SIS size, wires between 18 AWG and 14 AWG are typically marked “Suitable for switchboard use.”
How is SIS Wire Constructed?
SIS wire features a single tinned copper conductor, offered in solid or stranded designs depending on the size. Constructions between 18 AWG and 12 AWG may be solid or stranded, while larger sizes are stranded only. The insulation is XLPE, a thermoset compound known for its durability, resistance to moisture, chemicals, and oils, and inherent flame-resistant properties. Most SIS constructions meet WV-1 fire test requirements.
SIS Dual Ratings
Many SIS wires carry additional UL ratings, including:
- UL 3173: Internal appliance wiring; 125°C; 600 volts; 26–9 AWG; must pass horizontal flame test.
- UL 3195: Internal wiring; applies only to 8 AWG conductors.
- UL 3196: Internal wiring; covers 7–2 AWG.
- UL 3320: Motor lead and internal appliance wiring; 30–2 AWG; 90°C; 600V AC continuous; insulation must withstand 2,500-volt surge; may be labeled “2,500 volts peak — for electronic use only.”
Does Allied Wire & Cable Carry Other SIS Wire Brands?
AWC also supplies SIS wire from Belden, including Belden SIS Hook-Up Wire.
SIS Wire Specifications
| Conductor: | Tinned Copper, stranded or solid |
| Insulation: | Thermoset XLPE |
| Voltage Rating: | 600 volts AC continuous |
| Temperature Rating SIS: | 90°C |
| Dual Temperature Rating: | 90°C to 125°C depending on UL Type |
| Fire Rating: | Many constructions comply with VW-1 vertical flame test |
| Colors: | Multiple colors available |
| NEC Rating: | SIS |
| CSA Rating: | SIS / CL1251 |
| UL Types: | UL 3173, UL 3195, UL 3196, UL 3320 |
| Chemical Resistance: | Good |
| Oils & Hydraulic Fluid Resistance: | Good |
| Sizes: | 18 AWG – 4/0 AWG |
Contact us for assistance selecting SIS wire for your application..