EC&M’s Electrical Calculations Handbook - Chapter 3 potx

... capacitance. 82 72 Chapter Three Figure 3- 1 (Continued) -J 45 ° 60 ° +J NEW RESULTANT 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, ... vector. +X +J -J (-X, -J) NEW RESULTANT VECTOR -1 6.6 +j 12.7 180 ° - 37 .4 ° AMP 20.9 (-X, +J) (+X, -J) 142.6 ° (+X, +J) 37 .4 ° Step 4. Determine...

Ngày tải lên: 13/08/2014, 02:21

... 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 ... ampacity. Conductors 1 63 DETERMINE AMPACITY FROM NEC TABLE REMARKS 31 0-1 6 OR 31 0-1 7 31 0-1 6 OR 31 0-1 7 UNDER...

Ngày tải lên: 13/08/2014, 02:21

... 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 5000-hp motor 4. The 200-hp motor 5. The 40-hp ... Fig. 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 gene...

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... 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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... receptacle device installation personnel hours. 37 7 Figure 1 5-5 Heavy-wall rigid-steel installation personnel hours. 38 3 neering economic studies. A cash-flow diagram shows any money received as an ... 1 420 Chapter Fifteen Figure 1 5-2 3 Solve for the cash-flow diagram of a loan transaction at interest. Figure 1 5-2 4 Solve for the cash-flow diagram of a recurrent savings se...

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... load 1 3- 1 Conductor size for general load 1 3- 8 Conductor size for general receptacle load 1 3- 4 Conductor size for household appliance 1 3- 3 Conductor size for HVAC load 1 3- 5 Conductor size for self-regulated ... 32 3 Medium-Voltage and Special-Purpose Circuit Breakers and Relay Controllers 32 5 Chapter 13. Circuits for Special Loads 33 5 Designing Circuits for Various Ele...

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... Volt, 3- phase 4-wire wye Note 5 460 Volt, 3- phase 3- wire delta Note 4 600 /34 7 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 ... next. Three-Phase Systems 57 SYSTEM VOLTAGE Notes 220 Volt single-phase Note 1 220 /38 0 Volt 3- phase 4-wire wye Note 2 33 00/1900 Volt, 3- phase 4-wire wye 6600 /38 00...

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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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... 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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... 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 ... form, showing that in a wye-con- nected system the phase-to-phase voltage is equal to the coil voltage multiplied by the square root of 3. Three-phase wye Figure...

Ngày tải lên: 13/08/2014, 02:21