I?m still not following. To me, VA means V times A, 1? = V X A & 3? = V X A X 1.732.
For Motor Feeders, or any feeder, there should also be an additional 25% of the largest motor added to the summation; But what establishes the Amperage for mixed Continuous and Non-continuous Motors, to find circuit VA? T430.147-150 state values of full load motor current; Part II of 430 specifies ampacities of conductors, and 230.3(B)(3) outlets for motor loads.
Is this the correct way to calculate O.C.P.D.?s (Inverse Time Circuit Breakers) and total V.A. for Motor Feeder Circuits; Continuous and Continuous with Duty Cycle Motors?
(No Name Plate F.L.A. given)
10 HP (one) 3? 208V Continuous 30.8A @ 100% T430.150
5 HP (two) 1? 208V Continuous 30.8A @ 100% T430.148
2 HP (three) 1? 120V Continuous 24A @ 100% T430.148
30.8 X 250% = 77 = 80A Branch CB 430.52(C)(1) & 240.6
80 + (2 X 30.8) + 24 = 165.6 = 150A Feeder CB 430.62(A) & 240.6
(208 X 1.732 X 30.8) + (2 X 208 X 30.8) + (3 X 120 X 24) + (30.8 X 25%) =
32,557 Total Feeder Circuit VA
The same motor configuration, except: the two (5HP 208V 1-Phase) motors are now classified as ?Intermittent Duty?, 15 Minute Rated motors; and the three (2 HP 120V 1-Phase) motors are now classified as ?Varying Duty?, Continuous Rated motors.
Comparison for largest motor: per (430.24 Exc.1)
10 HP 3? 208V 30.8A @ 125% Continuous = 38.5A 430.24 (Exc.1)
5 HP 1? 208V 30.8A @ 85% Intermittent Duty = 26.18A T430.22 (E)
2 HP 1? 120V 24A @ 200% Varying Duty = 48A T430.22 (E)
10 HP (one) 3? 208V Continuous 30.8A @ 100% T430.150
5 HP (two) 1? 208V Intermittent Duty 26.18A @ 85% T430.22 (E)
2 HP (three) 1? 120V Varying Duty 48A @ 200% T430.22 (E)
48 X 250% = 120 = 125A Branch CB 430.52 (C)(1) & 240.6
125 + (2 X 26.18) + 30.8 = 208.16 = 200A Feeder CB 430.62 (A) & 240.6
(A) By Motor Table FLC (208 X 1.732 X 30.8) + (2 X 208 X 30.8) + (3 X 120 X 24) + (30.8 X 25%) = 32,556 Total Feeder Circuit VA
(B) By Motor Rating (208 X 1.732 X 30.8) + (2 X 208 X 26.18) + (3 X 120 X 24) + (30.8 X 25%) = 30,634 Total Feeder Circuit VA
(C) By Motor Duty (208 X 1.732 X 30.8) + (2 X 208 X 26.18) + (3 X 120 X 48) + (48 X 25%) = 39,279 Total Feeder Circuit VA
Any Help would be greatly appreciated, as the ?Grand fathers? in WA runs out on 7/1, and I take
Part III for the third time on 6/29.
For Motor Feeders, or any feeder, there should also be an additional 25% of the largest motor added to the summation; But what establishes the Amperage for mixed Continuous and Non-continuous Motors, to find circuit VA? T430.147-150 state values of full load motor current; Part II of 430 specifies ampacities of conductors, and 230.3(B)(3) outlets for motor loads.
Is this the correct way to calculate O.C.P.D.?s (Inverse Time Circuit Breakers) and total V.A. for Motor Feeder Circuits; Continuous and Continuous with Duty Cycle Motors?
(No Name Plate F.L.A. given)
10 HP (one) 3? 208V Continuous 30.8A @ 100% T430.150
5 HP (two) 1? 208V Continuous 30.8A @ 100% T430.148
2 HP (three) 1? 120V Continuous 24A @ 100% T430.148
30.8 X 250% = 77 = 80A Branch CB 430.52(C)(1) & 240.6
80 + (2 X 30.8) + 24 = 165.6 = 150A Feeder CB 430.62(A) & 240.6
(208 X 1.732 X 30.8) + (2 X 208 X 30.8) + (3 X 120 X 24) + (30.8 X 25%) =
32,557 Total Feeder Circuit VA
The same motor configuration, except: the two (5HP 208V 1-Phase) motors are now classified as ?Intermittent Duty?, 15 Minute Rated motors; and the three (2 HP 120V 1-Phase) motors are now classified as ?Varying Duty?, Continuous Rated motors.
Comparison for largest motor: per (430.24 Exc.1)
10 HP 3? 208V 30.8A @ 125% Continuous = 38.5A 430.24 (Exc.1)
5 HP 1? 208V 30.8A @ 85% Intermittent Duty = 26.18A T430.22 (E)
2 HP 1? 120V 24A @ 200% Varying Duty = 48A T430.22 (E)
10 HP (one) 3? 208V Continuous 30.8A @ 100% T430.150
5 HP (two) 1? 208V Intermittent Duty 26.18A @ 85% T430.22 (E)
2 HP (three) 1? 120V Varying Duty 48A @ 200% T430.22 (E)
48 X 250% = 120 = 125A Branch CB 430.52 (C)(1) & 240.6
125 + (2 X 26.18) + 30.8 = 208.16 = 200A Feeder CB 430.62 (A) & 240.6
(A) By Motor Table FLC (208 X 1.732 X 30.8) + (2 X 208 X 30.8) + (3 X 120 X 24) + (30.8 X 25%) = 32,556 Total Feeder Circuit VA
(B) By Motor Rating (208 X 1.732 X 30.8) + (2 X 208 X 26.18) + (3 X 120 X 24) + (30.8 X 25%) = 30,634 Total Feeder Circuit VA
(C) By Motor Duty (208 X 1.732 X 30.8) + (2 X 208 X 26.18) + (3 X 120 X 48) + (48 X 25%) = 39,279 Total Feeder Circuit VA
Any Help would be greatly appreciated, as the ?Grand fathers? in WA runs out on 7/1, and I take
Part III for the third time on 6/29.