The series motor has poor speed regulation. When the load speed of the machine increases, the DC shunt motor keeps its constant speed from no load to full load. The dc series motor’s Torque drops sharply when the speed increases.
What is the advantage of a series motor?
The series motor has the highest starting torque for a given power rating. When the motor is overloaded, the speed drops and the torque increases. While delivering high torque during an overload, the series motor draws less current and power from the source compared to a shunt or compound DC motor.
What is the main disadvantage of a series wound generator?
Disadvantages of DC series motors:
It is necessary to have a load before starting the DC series motor. So the series motor is not good to use load does not apply to the initial stage. When the speed is increased then the DC series motors torque will be decreased sharply.
What is the main disadvantage of shunt motor?
As the load changes, a shunt wound motor runs at a predictable speed. If variable speed is desired, constant speed can be a disadvantage. The lifetime of the motor is usually not improved by brushes.
What is the main advantage of a series parallel motor over a series motor?
Thus the speed will be less. If the series motors are connected in parallel, each and every armature of the motor receives the full normal voltage and hence the speed is also high. Thus we can achieve the two speeds (low or high) by connecting the motor either in series or parallel.
What are the characteristics of a series motor?
Series Motors
A characteristic of series motors is the motor develops a large amount of starting torque. However, speed varies widely between no load and full load. Series motors cannot be used where a constant speed is required under varying loads.
What are the disadvantages of DC motor?
Disadvantages of DC motors
- High initial cost.
- Increased operation and maintenance cost due to the presence of commutator and brush gear.
- Cannot operate in explosive and hazard conditions due to sparking occur at brush (risk in commutation failure)
What are the advantages and disadvantages of a DC shunt motor?
The installation of DC machines is expensive compare with other types of machines. Shunt motor is a constant speed motor, it would be disadvantages where it’s necessary to operate under variable speed. For the same current input, its starting torque is not a high as that of a DC series motor.
Why is the chief advantage of a DC series motor?
The primary advantage of the DC motor is that it can develop constant torque over a wide speed application. Power supply is an important consideration in the application of DC motors. The most common way to provide DC voltage to a motor from an AC line is through the use of an electronic drive.
Which has stronger torque series motor or shunt motor?
The field flux, then is proportional to armature current.For light loads a series motor produces less toryue for the same arrnature current; for heavy loads it produces more torque than a shunt motor. Series motors are alwaye rigtdly connected to their loads, and never operated without some Ioad.
What are the disadvantages of shunt?
There are some disadvantages of a transistor shunt regulator are given below,
- It has poor efficiency for large load currents.
- It has high output impedance.
- The output DC voltage is not absolutely constant because both VBB and VZ voltages decrease with increase in room temperature.
What is the difference between shunt and series motor?
A series motor respond by decreasing its speed with small increase in current for a given load torque. A shunt motor holds its speed nearly constant with large increase in input current for same amount of load torque.
What is series motor?
A series motor is a direct current motor that has two windings that are in series, with the same current flowing through each.The series motor provides high starting torque and is able to move very large shaft loads when it is first energized.
What are the disadvantages of series connection?
A disadvantage of series circuits is that if there is a break or fault at any of the appliances connected to the circuit, the remaining appliances will be cut from the supply. Regarding parallel circuits, appliances can be connected and disconnected to the circuit without affecting other parts of it.
What are the advantages and disadvantages of series?
To construct the parallel connection, we need lots of wires. We can connect or disconnect a new electric appliance in the circuit without affecting the other components in the circuit. We cannot meet the requirement when the exact same amount of current is required to pass through the element.
What are the advantages and disadvantages of series combination?
What are the advantages and disadvantages of a series combination?
- Cells connected in series give a greater resultant voltage than individual cells.
- Voltage increases if the number of cells increases.
- Series circuits do not overheat easily.
What are the advantages and disadvantages of Hopkinson’s test?
It is difficult to find two identical machines needed for Hopkinson’s test. Both machines cannot be loaded equally all the time. It is not possible to get separate iron losses for the two machines though they are different because of their excitations.
What are the principle characteristics of a series dc motor?
DC series motors are always connected to loads by gears so that minimum load is always maintained to keep the speed with in safe limits. Since a series motor develops high starting torques at low speeds and low torque at high speeds, therefore, speed torque characteristics of a DC series motor is a hyperbola.
What will happen if we run a DC series motor without load?
Thus from equation (2), it is clear that speed of DC Series Motor is inversely proportional to Armature Current Ia.Therefore if the DC Series Motor is started at No Load then the speed of DC Series Motor will become dangerously high which will definitely damage the DC Series Motor.
What are the disadvantages of compound Motors?
Disadvantages of Compound Motors
- Operation and maintenance cost of DC motors are expensive.
- DC motors unable to operate in hazard situation where spark occurs at the brush of the motor.
- In generally Every DC motor using brushes so the lifetime of such motors is less compared with AC motors.
What are the disadvantages of DC electricity?
Disadvantages of DC Transmission:
Due to commutation problem, electric power can’t be produced at High (DC) Voltage. In High Voltage transmission, we cant step-up the level of DC Voltage (As Transformer won’t work on DC). There is a limitation of DC switches and circuit breakers (and they are costly too).
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