What will happen to a DC series motor when its load is removed?
What occurs if the load is removed from an operating series DC motor? It will stop running. Speed will increase slightly.
What may happen to a series motor if it is connected to power without having a load?
If u start the motor without load the speed will increase. as speed increases the back emf increases. this decreases the current through the series winding and hence flux decreases and the speed further increases. Theorerically speaking the speed becomes infinite.
What will happen when the series self excited DC motor operate at no load?
Self-excited, shunt DC generator operating at no load The magnetization curve produced when the machine is separately excited still applies. Because the load current is zero, the only current in the armature winding is the field current.
Can a DC series generator excite on no load?
Armature current of any DC motor depends upon load. Hence if load increases armature current (Ia) also increases and vice versa. At no load condition, load on the motor is zero hence armature current(Ia) is also zero. From equation (i) (If=Ia) hence field current(If) will also=0 at no load condition.
Which DC motor is preferred for constant speed?
Explanation: Rotary compressor generally demand constant speed operation throughout the load. Sometimes, DC machines are not able to produce constant speed throughout the process hence, synchronous machine is used. 4.
What happened to the DC motor if it run without any starter explain in details?
What will happen if DC motor is used without starter? Explanation: It would cause intolerably heavy sparking at the brushes which may destroy the commutator and brush-gear. Sudden development of large torque will cause mechanical shock to the shaft, reducing its life.
Which motor has the poorest speed control?
1. Which of the following DC motor has the poorest speed control? Explanation: DC series motor at no load condition gives infinite speed ideally. Practically it will damage all the armature circuit.
Is the speed of a DC shunt motor is increased the back emf of the motor will?
So, the back emf is directly proportional to speed. Hence, when the speed of a DC shunt motor is increased, then the back emf of the motor will increase.
Why should a DC series motor always be started with load?
When the motor is connected across the supply mains without load, it draws small current from the supply mains. … The increase in back emf weakens the armature current and hence the field current. This cause again increases the speed so the back emf.