Question

In: Electrical Engineering

The resistance of a starter for a 200-V, shunt motor is such that maximum starting current...

The resistance of a starter for a 200-V, shunt motor is such that maximum starting current is 30 A. When the current has decreased to 24 A, the starter arm is moved from the first to the second stud. Calculate the resistance between these two studs if the maximum current in the second stud is 34 A. The armature resistance of the motor is 0.4 Ω.

ANSWER [1.334 Ω]

Solutions

Expert Solution


Related Solutions

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 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 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,...
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 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...
Assuming n=m=1 A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm...
Assuming n=m=1 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 a. Field current at no load b. Armature current at no load c. Rotational loss at no...
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...
A 240 V DC shunt motor draws 40 A while driving a constant torque load. The...
A 240 V DC shunt motor draws 40 A while driving a constant torque load. The armature resistance is Ra = 0.2 Ω, the field resistance is Rf = 240 Ω and machine constant is Ka = 120. The part of magnetization characteristic (field flux versus field current) related to the question is: If (A) :      0.70 0.80 0.86 0.90 1.00 1.10 1.20 1.30 1.40 ϕ (mWb) : 5.80 6.30 6.59 6.70 7.20 7.60 7.96 8.20 8.45 The constant rotational...
What does Shunt resistance mean? What are the differences between serious and shunt?
What does Shunt resistance mean? What are the differences between serious and shunt?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT