ELECTRICAL CODE CALCULATIONS, LEVEL II, LESSON 3: RANGE
AND APPLIANCE CALCULATIONS EXAM #23
The minimum branch-circuit rating for a household range rated 83/4 kw shall not be less
than - correct answer The correct answer is: 40 A
The correct answer is: 210.19(A)(3)
When a household wall-mounted oven is tapped from a 50-ampere branch circuit, the
ampacity of the tap conductors shall not be less than ? . - correct answer The correct
answer is: 20 A
The correct answer is: 210.19(A)(3) Exception No. 1
The minimum size neutral conductor permitted for a household wall-mounted oven,
electric range, or cooking unit rated 83/4 kw or larger is ? . - correct answer The correct
answer is: 10 AWG
The correct answer is: 210.19(A)(3) Exception No. 2
The neutral feeder demand for household electric ranges is permitted to be ? Of the
feeder demand for the ungrounded conductors. - correct answer The correct answer is:
70%
The correct answer is: 220.61(B)
What is the ungrounded conductor feeder demand for one 10 kw household range
installed in a dwelling unit? - correct answer Table 220.55, Column C
1 range = 8 kw
Line = 8 kw or 8,000 VA
The correct answer is: 8000
What is the ungrounded conductor feeder demand for two 10 kw household ranges in a
dwelling unit? - correct answer Table 220.55, Column C
2 ranges = 11 kw
Line = 11 kw or 11,000 VA
The correct answer is: 11000
What is the ungrounded conductor feeder demand for household electric ranges
installed in a four-unit multifamily dwelling when the ranges are rated 8.8 kw, 9 kw, 10
kw, and 12 kw? - correct answer 4 ranges not over 12 kw
Table 220.55, Note 2 and Column C
4 ranges = 17 kw
Line = 17 kw or 17,000 VA
, The correct answer is: 17000
What is the ungrounded conductor feeder demand for two 14 kw household electric
ranges installed in a dwelling unit? - correct answer Table 220.55, Note 1
14 kw exceeds 12 kw by 2
Increase 5% per kw over 12
100% + (2 × 5%) = 110%
Table 220.55, Column C
2 ranges = 11 kw
Line = 11 kw × 1.10
= 12.1 kw or 12,100 VA
The correct answer is: 12100
Based on single-phase feeders for household range loads rated in volt-amperes (VA)
for the ungrounded conductors of a single-phase system, identify the Code compliant
minimum rating in volt-amperes for the grounded conductor of each feeder. - correct
answer The correct answer is:
8,000 VA line-to-line demand → 5,600 VA neutral demand,
11,000 VA line-to-line demand → 7,700 VA neutral demand,
12,100 VA line-to-line demand → 8,470 VA neutral demand,
17,000 VA line-to-line demand → 11,900 VA neutral demand
One 10 kw range, one 15 kw range, and one 24 kw range are to be installed in a
multifamily dwelling. What is the feeder demand for the three household ranges for the
ungrounded conductors only? - correct answer Table 220.55, Note 2
Over 83/4 kw, Unequal ratings
Average ratings using 12 kw for any range less than 12 kw
Use 12 kw (for 10 kw range)
Total Loads = 12 + 15 + 24
= 51 kw
Average load = 51 ÷ 3
= 17 kw
17 kw exceeds 12 kw by 5 kw
100% + (5 × 5%) = 125%
Table 220.55, Column C
3 ranges = 14 kw
Line = 14 kw × 1.25
= 17.5 kw → 17,500 VA
The correct answer is: 17500
What is the branch-circuit demand load for a 2 1/2 kw household cooktop and a 2 kw
household oven for a dwelling unit (based on the ungrounded conductors of a single-
phase, 3-wire feeder)? - correct answer Table 220.55, Note 4
AND APPLIANCE CALCULATIONS EXAM #23
The minimum branch-circuit rating for a household range rated 83/4 kw shall not be less
than - correct answer The correct answer is: 40 A
The correct answer is: 210.19(A)(3)
When a household wall-mounted oven is tapped from a 50-ampere branch circuit, the
ampacity of the tap conductors shall not be less than ? . - correct answer The correct
answer is: 20 A
The correct answer is: 210.19(A)(3) Exception No. 1
The minimum size neutral conductor permitted for a household wall-mounted oven,
electric range, or cooking unit rated 83/4 kw or larger is ? . - correct answer The correct
answer is: 10 AWG
The correct answer is: 210.19(A)(3) Exception No. 2
The neutral feeder demand for household electric ranges is permitted to be ? Of the
feeder demand for the ungrounded conductors. - correct answer The correct answer is:
70%
The correct answer is: 220.61(B)
What is the ungrounded conductor feeder demand for one 10 kw household range
installed in a dwelling unit? - correct answer Table 220.55, Column C
1 range = 8 kw
Line = 8 kw or 8,000 VA
The correct answer is: 8000
What is the ungrounded conductor feeder demand for two 10 kw household ranges in a
dwelling unit? - correct answer Table 220.55, Column C
2 ranges = 11 kw
Line = 11 kw or 11,000 VA
The correct answer is: 11000
What is the ungrounded conductor feeder demand for household electric ranges
installed in a four-unit multifamily dwelling when the ranges are rated 8.8 kw, 9 kw, 10
kw, and 12 kw? - correct answer 4 ranges not over 12 kw
Table 220.55, Note 2 and Column C
4 ranges = 17 kw
Line = 17 kw or 17,000 VA
, The correct answer is: 17000
What is the ungrounded conductor feeder demand for two 14 kw household electric
ranges installed in a dwelling unit? - correct answer Table 220.55, Note 1
14 kw exceeds 12 kw by 2
Increase 5% per kw over 12
100% + (2 × 5%) = 110%
Table 220.55, Column C
2 ranges = 11 kw
Line = 11 kw × 1.10
= 12.1 kw or 12,100 VA
The correct answer is: 12100
Based on single-phase feeders for household range loads rated in volt-amperes (VA)
for the ungrounded conductors of a single-phase system, identify the Code compliant
minimum rating in volt-amperes for the grounded conductor of each feeder. - correct
answer The correct answer is:
8,000 VA line-to-line demand → 5,600 VA neutral demand,
11,000 VA line-to-line demand → 7,700 VA neutral demand,
12,100 VA line-to-line demand → 8,470 VA neutral demand,
17,000 VA line-to-line demand → 11,900 VA neutral demand
One 10 kw range, one 15 kw range, and one 24 kw range are to be installed in a
multifamily dwelling. What is the feeder demand for the three household ranges for the
ungrounded conductors only? - correct answer Table 220.55, Note 2
Over 83/4 kw, Unequal ratings
Average ratings using 12 kw for any range less than 12 kw
Use 12 kw (for 10 kw range)
Total Loads = 12 + 15 + 24
= 51 kw
Average load = 51 ÷ 3
= 17 kw
17 kw exceeds 12 kw by 5 kw
100% + (5 × 5%) = 125%
Table 220.55, Column C
3 ranges = 14 kw
Line = 14 kw × 1.25
= 17.5 kw → 17,500 VA
The correct answer is: 17500
What is the branch-circuit demand load for a 2 1/2 kw household cooktop and a 2 kw
household oven for a dwelling unit (based on the ungrounded conductors of a single-
phase, 3-wire feeder)? - correct answer Table 220.55, Note 4
