The answer is efficiency of the motor will be minimum.
19. When the maximum torque of three phase induction motor is obtained at high slip: (3...
Three-phase induction motor The three-phase induction motor nameplate gives the following information: 100 HP, 6 poles, 600 V, 60 Hz, PF =0.87. Rated motor slip s=0.0275 and rated motor current is 91.7 A. Measured at rated speed friction and ventilation losses are 1100 W. Measured between two motor terminals resistance is 0.305 Ω. f) For a load such where the motor rotates at the speed of 1180 r / min, determine shaft torque and calculate the mechanical power in HP,...
20 horsepower, 380V, 60Hz 6-pole 3-phase induction motor has 6% of full load slip. When operated under full load, friction and wind damage are 220W, stator copper loss is 270W, and iron loss is 200W. Find the following under full load. a. Load torque b. Organic torque c. Pore power d. efficiency
A 3-phase, 460 V, 1740 rpm, 60 Hz, 4-pole wound-rotor induction motor has the following parameters per phase: R1 = 0.25 Ω, ' 2R = 0.2Ω, ' 1 2 X = X = 0.5Ω, 30 m X = Ω. The rotational losses are 1700 W. With the rotor terminals short-circuited, find: 1. at starting: • current when started direct on full voltage, • a torque 2. at full load: • slip • current • ratio of starting current to full-load...
Question 11: (3 marks) A 6 pole, 60 Hz, star connected three-phase induction motor has a rating of Pm = 55 kW and line voltage = 420 V. The slip of the motor is 2% at 0.9 power factor lagging. If the full load efficiency is 95%, calculate the torque developed in the motor.
Problem # 3: Induction Motor Analysis [30 points] The parameters of the per phase equivalent circuit of a three phase wye-connected, 220 V (line- line, rms) 10 hp, 60 Hz, six-pole induction motor are given as: Ri = 0.3 Ohm, R2-0.15 Ohm, Xi-0.5 Ohms, X2= 0.2 Ohm, Xm-15.0 The total friction, windage and core losses add up to be a constant of 400 W. For a slip of 0.025 with motor operating at rated frequency and stator voltage, calculate the...
4. A 110-volt, 4-pole single phase induction motor with rl-1.3, r2-3, xl-2.5, x2-2, and xm-50, operates at full load slip of 3%. Find the full load torque, power facor and ficiency 20 points 4. A 110-volt, 4-pole single phase induction motor with rl-1.3, r2-3, xl-2.5, x2-2, and xm-50, operates at full load slip of 3%. Find the full load torque, power facor and ficiency 20 points
Problem 2. (25 points) For a 120-V, 1/3 hp, four pole, 1-phase induction motor, the parameters of the equivalent circuit, are R,-1.8(2, R,-2.5Ω, X,-X,-2.462, and Xm-60 Ω. At a slip of 500, the motor's rotational losses are 51W. The rotational losses maybe assumed constant over the normal operating range of the motor. If the slip is 0.05, calculate a. Input Power b. Air Gap Power, c. Induced Torque Tin d. Output power e. Load torque. f. Overall Motor efficiency g....
Question 2 [10 marks) A six pole, three phase induction motor, with a star connected stator winding is energised from a 380V, 50Hz supply. The ratio of the stator to rotor turns is assumed 1.8 and a full load slip of 4%. If the respective per phase rotor resistance and standstill reactance are 0.120 and 0.8502, determine: a. Torque developed at full load b. The maximum torque and the speed at maximum torque
Problem#(50 points) The nameplate for a three phase induction motor is shown below. The "NEMA NOM. EFF." of 93.6% can be taken to be the efficiency. Keep in mind that voltage and current in a 3PH system are specified as line voltage and current SIEMENS PE 21 PLUS PREMUM EFFICE 40 LL AND CHEMICAL DUITY QUALL Part A Assume the motor is run at the rated nameplate conditions: (a) Find the real electrical input power. (b) Find the numerical value...
Two tests were performed on a 230-V, 60-Hz, 4-pole, Y-connected, three-phase induction motor and the obtained data are given in the table below. The friction and windage loss is 15 W, and the stator winding resistance between any two lines is 3.96ohm Determine: 1) The equivalent circuit parameters of the motor 3) The motor efficiency at a slip of 8%. No-load test 137 0.43 230 Blocked-rotor test 70 1.18 47 3-phase power input, W Line-line voltage, V