For equipment exported to North America, the UL style number printed on the wire is the first checkpoint of safety review. Here is what those numbers mean.
The three common styles
- UL1007300V / 80°C / PVC / general internal wiring
- UL1015600V / 105°C / PVC / higher temp and voltage
- UL1332300V / 150°C / FEP / high temperature
1. Temperature first, then voltage
Wire life depends on temperature: ambient plus self-heating plus 10°C margin must stay under the rating.
2. Insulation decides flexibility and chemical resistance
PVC is soft and cheap with fair chemical resistance; FEP handles heat and chemicals but is stiffer and 3-5x costlier. For high flex life, use dedicated high-flex constructions instead.
3. AWG and ampacity
Within a style, thicker conductors carry more current: roughly 3A for 22AWG, 8A for 18AWG, 15A for 14AWG (80°C single-conductor reference; derate in bundles). With poorer heat dissipation in multi-conductor cables, apply a 0.8 derating factor.
4. Procurement: check markings
Legitimate UL wire carries printed style, voltage, temperature, AWG and vendor code, verifiable in the UL database. Never use unmarked wire.
Final words
We recommend UL styles per application and keep UL records. Send drawings: +86 184 0755 1752 / eric@muyenda.com.