a)In a 3-phase 4-wire circuit, a circuit breaker is selected to protect the circuit whose highest fault level is 6.6 MVA. Determine the required minimum breaking capacity in kA. (Note: Covert 3-phase power in terms of kA to find answer.) b)Using the below, determine the required minimum making capacity in kA as a “peak value”. Rate breaking capacity (Icn) ka: Icn<= 1.5 Factor = 1.41 1.5
11771. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.
1473what is the most permissible winding temp when we conducting a generator load test?(condition no load)
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Dear sir, iam completed iti ncvt electrician 2000-2002 & diploma electrical eng completed 2008-2010 distance education in rvd university, still i got B licences only but my working company want C licences, how to i get c licencese pls reply me iam in critical situation thank you karthick 9841637803
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132/6.6𝚔𝚟 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛 𝚗𝚎𝚞𝚝𝚛𝚊𝚕 𝚑𝚊𝚜 𝚘𝚗𝚎 𝚎𝚊𝚛𝚝𝚑 𝚙𝚒𝚝 𝚍𝚎𝚍𝚒𝚌𝚊𝚝𝚎𝚍. 𝙸'𝚟𝚎 𝚊𝚗𝚘𝚝𝚑𝚎𝚛 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛 𝚘𝚏 6.6𝚔𝚟/415𝚟 𝚌𝚊𝚗 𝙸 𝚌𝚘𝚗𝚗𝚎𝚌𝚝 𝚗𝚎𝚞𝚝𝚛𝚊𝚕 𝚝𝚘 𝚜𝚊𝚖𝚎 𝚎𝚊𝚛𝚝𝚑 𝚙𝚒𝚝 𝚊𝚜 𝚘𝚏 13/6.𝚔𝚟 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛?? 𝙸𝚏 𝙽𝚘.. 𝚃𝚑𝚎𝚗 𝚠𝚑𝚢??
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