Services, Grounding & Bonding第 58 / 120 题
A dry-type transformer rated 112.5 kVA or less is installed indoors. What is the minimum separation from combustible material unless it is separated by a fire-resistant heat-insulating barrier?
a.3 inches
b.6 inches
c.12 inches
d.18 inches
解析
Dry-type transformers of 112.5 kVA or less must be at least 12 inches from combustible material unless separated by a fire-resistant, heat-insulating barrier or unless the unit is completely enclosed except for ventilating openings. The smaller clearances listed belong to other rules such as recessed luminaire and insulation spacing, not to transformer installation.
法律依据: 2023 NEC §450.21(A)免费刷完整 120 道题库 — 无需注册。
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