The math you do on the truck.
Calculators and code reference. Built to be useful on the test and on the job. The math is the math, and the answer should match either way.
Calculators
Voltage Drop
Chapter 9 Table 8 + 210.19(A)
Round trip math for sizing conductors. The 2 multiplier is what trips most guys up.
Open calculatorBox Fill
Article 314.16
Counting conductors, grounds, and yokes. One ground equals one count. Yokes count as two.
Open calculatorConduit Fill
Chapter 9 Tables 1, 4, 5
53% for one conductor. 31% for two. 40% for three or more. Then Chapter 9 Table 4 for raceway area.
Open calculatorDwelling Load
Article 220
3 VA per square foot. Two SAs and a laundry. First 3,000 at 100%, the rest at 35%.
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