beanland
Senior Member
- Location
- Vancouver, WA
Same Insulation Type
Same Insulation Type
2011 NEC 310.10(H)(2)(4) states "Have the same insulation type" but it does not state anything more. If the insulation of all wires is thermoset, it is all the same type. If it is thermoplastic, it is all the same type. I do not think the NEC intended that if you have XHHW you cannot use XHHW-2 in parallel (limited by the lesser conditions of use). Same for THHW and THW. As long as the least conditions of use and temperature rating is applied to ALL conductors, no conductor will be operated out of its rating.
Same Insulation Type
2011 NEC 310.10(H)(2)(4) states "Have the same insulation type" but it does not state anything more. If the insulation of all wires is thermoset, it is all the same type. If it is thermoplastic, it is all the same type. I do not think the NEC intended that if you have XHHW you cannot use XHHW-2 in parallel (limited by the lesser conditions of use). Same for THHW and THW. As long as the least conditions of use and temperature rating is applied to ALL conductors, no conductor will be operated out of its rating.