FIGURE IT OUT
total continuous load that can be connected to a 70A fuse
70 x .80=56A
derating factor & amperage per conductor for 8 current carrying #8 THHN conductors in a raceway?
70%, 55 x .70=38.5A
total overcurrent for a 35A 277v continuous load circuit
43.75A / 45A
How many receptacles SHOULD be connected to a 15A residential
15A x 120 x .80 / 180 = 8
what is the full load current for a 208 v 1∅ 5hp motor?
21A x 1.25 = 26.25A, #10 THWN
Volt Amps for a 1∅ 50A. 277V Circuit
13,850 VA or 13.85 kVA (A x V)
What size XHHW copper conductor would be use to supply a 52A continuous load in an ambient temperature of 38°C?
52A x 1.25 x .91 =59.15, #6 XHHW
How many VA and 20A 120v circuits are required to feed 15’ of simultaneously used heavy duty multi-outlet assembly?
15’ x 180 = 2,700 VA , 20*120v=2,400 , 2700/2400=1.12 (2 ckts)
how many heavy duty lamp holder can be connected to a 30A 120v circuit ?
30 x 120 = 3600 / 600 = 6
how many receptacles CAN be connected to a 15A residential circuit?
15A x 120 = 1800 VA / 180 =10
What size conductors would be used for a A/C with a nameplate rating of 35A 220v 1∅?
35 X 1.25=43.75A =#6 AWG
Volt amps for a 3∅ 225A 480V Circuit
187,056 or 187.056 kVA (AxVx1.732)
What is the voltage drop for a 50A, 480V, 3∅ circuit, 340’ long
1.732x340x.491x50/1000=14.45v
what is the total demand (kW) for an electric range rated at 13.5kW?
13.5kW - 12kW = 1.5 8 x .05=.4 x 1.5=.6 + 8 = 8.6
How many 200W continuous duty lamps can be connected to a 20A 120V circuit?
200x 1.25=250, 2400/250=9.6 (9 total)
What is the total VA required for a residence with 4 kitchens?
(2 x 1500VA x 4= 12000VA)
What size THWN conductors would be used for a 460v 3∅ 15hp motor design letter B ?
21A x 1.25 = 26.25A, #10 THWN
What is the total amperage of a load with a nameplate rating of 3∅ 480V 3750w?
3750/480X 1.732=13.53A
what is the total voltage drop for a single phase 277V circuit using 100A aluminum conductors, 220’ long?
2x 220’x21.2x100/105600=8.83v
what is the total demand kVA for 4 commercial ovens rated at 5kW 208 3∅ each?
5000 x 4 = 20,000 x .80 x 1.732 =27.7 kVA.
what is the overall recommended percentage for a branch circuit?
3%
What is the total VA required for a residence with 4 laundry rooms?
4 x 1500VA = 6000VA
What size non- time delay fuse would be used for a continuous 460v 3∅ 7.5 hp motor design letter E?
11A x 1.25 x 3 = 41.25A, 45A fuse
What is the total circuit ampacity of a 6.75 kW load on a 1∅ 220V?
6.75x1000=6750/220=30.68A
How many VA and 20A 120v circuits are required to feed 75’ of show window?
200 x 75=15000 x 1.25= 18,750/ 2400=7.81(8-20a ckts)
What size THHN conductors and overcurrent would be required for a 120-gallon water heater rated at 8,500w at 240V?
8500 /240V = 35.41*1.25=44.27A (#8 THHN / 45A)
total amp rating for a commercial 277v circuit with 1x light fixture at 1500W and 2 x 3.5A lights that are on for 9 hours a day?
(1500/277=5.41A, 3.5 x2=7, 5.41 + 7x 1.25 = 15.5 A)
what is the total demand VA for 6 residential dryers rated at 4875va each?
5000 x 6 x .75=22,500VA
What size THHW copper conductor and circuit breaker would be required to supply a resistance welder with a nameplate rating of 65A with a 70% duty cycle?
65 x .86 = 55.9, #4 THHW, 55.9x 300% = 167.7A , 175A breaker
total overcurrent size for a 120v circuit with a non-continuous load of 15A and 2x 2.5A continuous loads?
2.5x2x 1.25 +15=21.25=25A