A 440 VDC, 60hp, cumulative compound long shunt motor has an armature resistance of .1 Ohm,...

A 440 VDC, 60hp, cumulative compound long shunt motor has an armature resistance of .1 Ohm, a series field resistance of ??? Ohms and a shunt field resistance of 80 Ohms. The brush drop is a constant 2 volts. The stray losses are 2.5 kW. The CEMF at rated load is 393 volts. Draw the electrical circuit, then determine the following for the above conditions:

A. The armature current:

B. The power developed by the armature:

C. The resistance of the series field:

D. The starting current if motor is directly connected across the 440 line voltage?

E. The value of a starting resistor to limit the initial current to 150A.

F. The nominal line current when operating at full load?

Solutions

Expert Solution

In case you have any doubts or you did not understand any step please feel free to ask your doubts in the comments section. I would be happy to clarify it.

Manojponduru answered 11 months ago

Next > < Previous

Related Solutions

A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm and a...

A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm and a shunt field resistance of 160+m Ohm . The motor operates at its rated speed with full load which takes 15+m Amp. A small of current of 2+.1*m A at no load due to rotational loses. Assume that rotational loss is proportional to the speed. Find Field current at no load Armature current at no load Rotational loss at no load Armature current at Full...

A 5-kW, 250-V shunt motor has an armature resistance of 0.1 ? and a field-circuit resistance...

A 5-kW, 250-V shunt motor has an armature resistance of 0.1 ? and a field-circuit resistance of 80 ?. When the motor is operating at rated voltage, the speed is observed to be 1200 r/min when the machine is loaded such that the armature current is 30 A. In order to protect both the motor and the dc supply under starting conditions, an external resistance will be connected in series with the armature winding (with the field winding remaining directly...

A shunt motor has a supply voltage of 200 V and armature resistance of 3.6 Ω....

A shunt motor has a supply voltage of 200 V and armature resistance of 3.6 Ω. At certain torque the motor run at speed = 1200 R.P.M and take a current of 10 Amp from the supply and its field current is 0.5 Amp. Find starting torque, no-load speed, and the load torque when the current supplied by the supply is 5 Amp.

A 100 hp, 220 V, 1200 rpm DC shunt motor with an armature resistance of 0.05...

A 100 hp, 220 V, 1200 rpm DC shunt motor with an armature resistance of 0.05 ? and a field resistance of 50 ?. The motor has compensating windings, so armature reactance can be ignored. Mechanical and core losses may be ignored also. The motor is driving a drilling machine, TL ? (1/n). The motor is driving a load with a line current of 120 A and an initial speed of 1200 rpm. Assume Linear Magnetization curve i. What is...

A 400 V dc shunt motor has a rated armature current of 76 A at a...

A 400 V dc shunt motor has a rated armature current of 76 A at a speed of 1000 rpm. The armature resistance of the motor is 0.4ohm, the field resistance is 100 ohm, and the rotational losses are 0.9 kW. The load of the motor is bidirectional. Calculate the following: (a) No-load speed of the motor. (b) Motor speed, where the armature current is 60 A during regenerative braking. (c) Developed torque during regenerative braking. (d) Back electromotive force,...

a) A 50kW separately excited DC motor has armature resistance of 2.5W, armature inductance of 30mH...

a) A 50kW separately excited DC motor has armature resistance of 2.5W, armature inductance of 30mH and back e.m.f of 100V when the motor is fed from a buck converter with 250VDC input, 50Hz switching frequency and 50% duty cycle. Assuming continuous conduction and lossless converter, find out the maximum, minimum and ripple currents in armature. b) Determine the values of inductor and filter capacitor for a buck converter with following specifications: Input= 48V, output = 24V, Load curernt =...

Q1A 4-poles, wave wound, 600 conductors DC long shunt generator has the armature, series and shunt...

Q1A 4-poles, wave wound, 600 conductors DC long shunt generator has the armature, series and shunt resistances are 0.15 ohm, 0.18 ohm and 200 ohm respectively. It runs at 1500 rpm. Calculate the following if it is required supply to the load resistance of 20ohm with flux per pole as 8.33 mWb. Take the Iron and Frictional losses as 550 W.(i)Induced Emf(ii)Terminal Voltage(iii)Output Power(iv)Input Power(v)Efficiency Q2Write short notes on following characteristics of dc generator(i) Open Circuit Characteristics (OCC)(ii) Load Characteristics...

Problem 5) A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance...

Problem 5) A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance of 0.05 Ω, a shunt field winding resistance of 200 Ω, and an armature resistance of 0.1 Ω. The machine is connected to 600 V DC source. The rotational loss is 3.2 kW. If the machine draws a 100 A from the supply, calculate a. Back EMF b. Determine the machine’s converted power (or developed power) and its efficiency. c. Determine the speed regulation...

a 240v, 4pole shunt motor running at 1000 r.p.m gives 15 hp with an armature current...

a 240v, 4pole shunt motor running at 1000 r.p.m gives 15 hp with an armature current of 50 A and field current of 1 A. the armature winding is wave connected and has 540 conductors. the armature resistance is 0.1 ohm and drop at each brush is 1v. find (i) useful torque, (ii) the total torque (iii) useful flux per pole, (iv) iron and friction losses

23 hp, dc shunt motor is running at 1000 rpm when the armature voltage is 600...

23 hp, dc shunt motor is running at 1000 rpm when the armature voltage is 600 V. The armature resistance of the motor is 0.8 ohm, and the field resistance is 900 ohm. The efficiency of the motor at full load is 92 %. a) Calculate the value of the resistance of the dynamic braking at full load. The armature current should be limited to 150% of the rated value. b) If the motor operated in regenerative braking at a...

Subjects