EC&M’s Electrical Calculations Handbook - Chapter 5 potx
EC&M’s Electrical Calculations Handbook - Chapter 5 potx
... 13.8-kV bus. Fault power is available to flow into this bus from 1. The electrical utility source 2. The 24-megawatt (MW), 30-MVA generator 3. The 50 00-hp motor 4. The 200-hp motor 5. The 40-hp ... 5- 2 . First, however, note that electrical short-circuit power can come from four sources in this circuit: 1. The 400,000-kVA electrical utility service 2. The 24-MW, 30-MVA generator 3....
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EC&M’s Electrical Calculations Handbook - Chapter 3 potx
... VECTOR 180 - 37.4° AMP 20.9 -1 6.6 +j 12.7 (-X, +J) (+X, +J) (-X, -J) (+X, -J) Step 3. Draw the resultant vector. +X +J -J (-X, -J) NEW RESULTANT VECTOR -1 6.6 +j 12.7 180 ° - 37.4 ° AMP 20.9 (-X, ... Ϫ90°. Mathematics 75 0 .57 6 -j 0.17 = (0 .57 6) 2 + (0.17) 2 ARCTAN (-0 .17/0 .57 6) ARCTAN (-0 .2 951 ) = 0.3607 = 0.6 -1 6.4 ° 1. Change vectors from rectangular to...
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EC&M’s Electrical Calculations Handbook - Chapter 4 potx
... 1 75 1 95 150 230 180 260 2 05 2 25 1 75 2 65 210 300 2 35 260 200 310 240 350 2 75 300 2 35 360 280 4 05 3 15 450 2 65 4 05 3 15 455 355 3 75 290 455 350 50 5 3 95 420 330 50 5 3 95 570 4 45 5 15 4 05 620 4 85 700 54 5 655 ... N.A. 20 N.A. 25 N.A. 12 25 20 25 20 30 25 10 30 25 35 30 40 35 84030 50 4 055 45 6 55 406 5 50 75 60 47 05 58 5 6 59...
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EC&M’s Electrical Calculations Handbook - Chapter 7 potx
... such as a 460-volt (V), three-phase, three-wire delta system, an arc- ing fault that repeatedly restrikes can cause voltage “jack- ing” of up to six times the normal system phase-to-neutral voltage. ... enough equipment-grounding conductors, as shown in Fig. 7-4 . Since system grounding is done at the service-disconnect- ing means, the equipment-grounding conductor and the neu- tral (“groun...
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EC&M’s Electrical Calculations Handbook - Chapter 15 potx
... Click here for Terms of Use. Figure 1 5- 1 9 Sample blank feeder takeoff sheet. 407 374 Figure 1 5- 1 Lighting fixture installation personnel hours. 3 75 Figure 1 5- 9 Installation personnel hours for ... 1 ᎏᎏ 0.08 (1 ϩ i) n Ϫ 1 ᎏᎏ i 418 Chapter Fifteen Figure 1 5- 2 2 Solve for the present value P of maintenance costs over the 2 0- year life of the generators. 376 Figure 1 5- 2...
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EC&M’s Electrical Calculations Handbook - Chapter 1 ppsx
... Value of Money 411 Chapter 16. Conversion Calculations 4 25 Temperature Conversion Calculations 4 25 Frequently Used Conversion Calculations 4 25 Multiple Conversion Calculations 4 25 Index 433 Contents ... characteristics 4-2 2 Heat losses of a copper bar from its dimensions and ampere load 8-1 Horizontal footcandle value using point method 4-1 1 Impedance of 600-V,...
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EC&M’s Electrical Calculations Handbook - Chapter 2 pptx
... Volt, 3-phase 4-wire wye Note 5 460 Volt, 3-phase 3-wire delta Note 4 600/347 Volt, 3-phase, 4-wire wye 2400 Volt, 3-phase, 3-wire delta 2400 Coltm 3-phase, 4-wire wye 4160/2400 Volt, 3-phase, 4-wire ... -j 104 = (180) 2 + (104) 2 Minus Phase b voltage - (120 120 ° = - 120 -6 0 ° ) = -( -1 20 COS 60 -j 120 SIN 60) = -[ (-1 20) (5) -j (120)(.866)] = -[ -6 0 +j 103.9...
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EC&M’s Electrical Calculations Handbook - Chapter 6 pdf
... rat- ing of the generator would be 0 .5 ϫ [1000 kW ϩ 6( 150 )], or 950 kilovoltamperes (kVA). Select a generator set that meets or exceeds both the 1 150 -kW and the 950 -kVA requirements and that has a ... is 1000 kW and a 150 -hp motor is to be started meanwhile, the minimum kilowatt rating of the generator would be 1000 kW ϩ 150 kW, or 1 150 kW, and the minimum kilovoltampere rat- ing of...
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EC&M’s Electrical Calculations Handbook - Chapter 8 pps
... necessary to use the point-by-point method. The Point-by-Point Method How to make point-by-point calculations Later in this chapter, lighting calculations within areas hav- ing reflective surfaces, ... footcandles from the second luminaire. Sample point-by-point lighting calculations Refer to Fig. 8-1 for sample point-by-point lighting calcula- tions for both the nadir point and a po...
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EC&M’s Electrical Calculations Handbook - Chapter 9 docx
... coil. 272 260 Figure 9-1 0 Table replicating part of NEC Table 45 0-3 (a), overcurrent protec- tion of transformers over 600 V. 274 Figure 9-1 2 Table replicating part of NEC Table 45 0-3 (b), overcurrent protec- tion ... (Hz) system, and it is 50 in a 50 -Hz system. Three-Phase Transformers Most of the transformers in operation in the electrical pow- er systems of the world t...
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