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, ... perpendicular to the lamp. 2 48 Chapter Eight Figure 8- 3 Zonal cavity calculation worksheet. 241 Figure 8- 2 Common lamps and their characteristics. 234 Footcandles ϭ The left side...

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... On-Site Generators 184 Short-Circuit Contributions of Motors 185 Let-Through Values of Transformers 187 Let-Through Values of Reactors 188 Let-Through Power Values of Cables 189 Sample Short-Circuit ... Selection 170 Chapter 5. Short-Circuit Calculations 179 Sources of Short-Circuit Current 182 The Ability of the Electrical Utility System to Produce Short-Circuit Current 183 Sho...

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... compensated for, Motors 289 300 Figure 1 0 -8 : Continuous-duty motors driving a continu- ous-duty load (pp. 300 and 301) Figure 1 0-9 : Continuous-duty motors driving an inter- mittent-duty load (pp. 302 ... 1.7 1.5 6.6 6 3 2.4 2 7.5 6 .8 3.4 2.7 3 10.6 9.6 4 .8 3.9 5 16.7 15.2 7.6 6.1 7.5 24.2 22 11 9 10 30 .8 28 14 11 15 46.2 42 21 17 20 59.4 54 27 22 25 74 .8 68 34 27 30 88 80...

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... interfere with one another? What minimum phase-to-phase and phase-to-ground dimensions must be maintained when con- structing an auxiliary wireway? This chapter provides con- venient answers to these questions ... Design and Layout Calculations 359 Electrical Design and Layout Calculations 365 Figure 1 4-3 Solve for working space in front of equipment operating at 0–150 V to ground....

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... work in the electrical industry, many other conversion calculations are encountered repeatedly. Figure 1 6-2 pro- vides the conversion formulas for these common conver- sions, and Fig. 1 6-3 is a set ... Use. Conversion Calculations Temperature Conversion Calculations While almost all ambient temperatures in electrical engi- neering are given in degrees Fahrenheit, almost all te...

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... 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)( .86 6)] = -[ -6 0 +j 103....

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... 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, ... x I x 3 /1000 kVA = 460 x 73 .83 x 3 /1000 kVA = 58. 823 ( 58. 823) = (50.000) 2 + (kVAR) 2 kVA 2 = KW 2 + kVAR 2 ( 58. 823) 2 - (50.000) 2 = (kVAR) 2 30. 986...

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... 90 2 1-2 5 7 0-7 7 1. 08 1.05 1.04 2 6-3 0 7 8- 8 6 1 1 1 3 1-3 5 8 7-9 5 0.91 0.94 0.96 3 6-4 0 9 6-1 04 0 .82 0 .88 0.91 4 1-4 5 10 5-1 13 0.71 0 .82 0 .87 4 6-5 0 11 4-1 22 0. 58 0.75 0 .82 5 1-5 5 12 3-1 31 0.41 0.67 0.76 5 6-6 0 ... 13 2-1 40 N.A. 0. 58 0.71 6 1-7 0 14 1-1 58 N.A. 0.33 0. 58 7 1 -8 0 15 9-1 76 N.A. N.A. 0.41 Figure 4-3 1 S...

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... electrical systems against damage during short-circuit conditions is required by the National Electrical Code (Secs. 11 0-9 and 11 0-1 0). Short-Circuit Calculations 181 For example, in a three-phase ... 30-MVA generator 3. The 5000-hp motor 4. The motors connected to the 480 -V bus Short-Circuit Calculations 191 Figure 5-1 Electrical power system one-line drawing for short-c...

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... power conductors and generator overcurrent pro- 200 Chapter Six Gas-turbine generators arrive at the installation site prepackaged on skids. Figure 6-2 Solve for generator overcurrent protection ... the watt load, and the elec- trical dynamo must be sized to allow selected motors to start while other selected electrical loads are in operation. Except in very unusual electrical system...

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