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Why external resistances are added to armature circuit in a dc motor?
Wiki User
∙ 12y ago
extra resistance is added in order to decrease starting current and improve starting torque
Wiki User
∙ 12y ago
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Why do you use slotted armatures in dc machines?
Those slots, or areas where metal was removed serve to balance the motor's armature. This is similar to the concept of "balancing" a wheel on a car.Metal material is 'shaved' or notched ( removed) from the side of the armature which is too heavy, ( and causes a ' wobble' as the RPM's are increased.)However, On a car, wheel weights are added to the OPPOSITE side of the wheel's heaviest spot of imbalance, until the wheel can be spun at a high speed, with no wobble.AnswerThe slots carry the armature conductors, while minimising the air gap between the rotor and and the stator (to minimise the reluctance of the magnetic circuit)!They have nothing to do with 'balancing' the armature.
What is separately excited DC motor?
The main difference between the Separately excited motor and the shunt motor is the field cct where as in the second it has its own voltage supply.AnswerI think you mean 'generator', not 'motor'. A 'self-excited' motor is one in which the output supplies the field current, as well as the load current. A 'separately-excited' motor is one in which the field current is provided from an external source.
Explain electronic circuit to break the electicity in case of short circuit?
A fuse or a circuit breaker can be added directly after the power source (and possibly a transformer) to do this.
Is resistance in a series circuit equal to the largest resistor in the series?
No. The resistance in a series circuit is all the resistor values added together. eg. If two resistors were in a circuit, one was 10 ohms and the other was 30 ohms, the resistance in the circuit would be 30 ohms. Hope this helps!
What is a driver transistor?
dirver transistor is added in a circuit so as to provide required voltage at an operating current which can not be provided by the microcontroller
What is the rule for the total resistors when resistors are added up in series?
You add the resistances together to get the total resistance in a series circuit. Say... R1=10 R2=12 R3=10 R123=32
What is mean by armature reaction?
armature reaction means when load is added to the armature then current is passed through armature conductors then in armature creates flux. It is demagnetize and cross magnetize the main field flux. in other ward it is effect of armature field on main field.
How does a series circuit work with an ammeter?
Actually ammeter is a galvanometer which is shunted by a resistance called shunt. For large currents major part of it is bypassed through the shunt. The parallel combination of shunt resistance and meter resistance is added to the circuit resistances , so the value indicated by the ammeter is slightly lesser than the actually value.
Why do you use slotted armatures in dc machines?
Those slots, or areas where metal was removed serve to balance the motor's armature. This is similar to the concept of "balancing" a wheel on a car.Metal material is 'shaved' or notched ( removed) from the side of the armature which is too heavy, ( and causes a ' wobble' as the RPM's are increased.)However, On a car, wheel weights are added to the OPPOSITE side of the wheel's heaviest spot of imbalance, until the wheel can be spun at a high speed, with no wobble.AnswerThe slots carry the armature conductors, while minimising the air gap between the rotor and and the stator (to minimise the reluctance of the magnetic circuit)!They have nothing to do with 'balancing' the armature.
Is there energy if no external motion or action is deserved?
I added "external" to the question
What is separately excited DC motor?
The main difference between the Separately excited motor and the shunt motor is the field cct where as in the second it has its own voltage supply.AnswerI think you mean 'generator', not 'motor'. A 'self-excited' motor is one in which the output supplies the field current, as well as the load current. A 'separately-excited' motor is one in which the field current is provided from an external source.
If you have a DC passing through a circuit will the current decrease when you add a DC motor and if so by how much?
In the circuit where the DC motor is added, it was not specified whether the motor was added in series or in parallel to circuit elements. If it was added in series, it will increase circuit resistance and it will cause circuit current to go down. In parallel, the motor will reduce total circuit resistance, and circuit current will increase.
What would happen if another bulb was added to another series circuit?
In a series circuit, if another bulb is added, it is going to dim.
If a new bulb is added and the electrical circuit becomes dimmer is it a parallel circuit?
No it's series circuit.
When you add resistors that are in a series to a ciruit?
You raise the total resistance by that amount if added in series to a circuit. If you add them in parallel to a circuit then that total resistance will be less than the total of the added circuit.
How do you add a fixture to an electrical circuit?
Any devices that are added to a circuit and need the full line voltage to operate, are added in parallel to any other load devices or fixtures in the circuit.
The differences between a series circuit and a parallel circuit?
In a series circuit, electrons flow through all the components one after another. If one fails (break), the whole circuit is no longer live. All the resistances are also added up in a series circuit. The current (measured in amps) is the same throughout the whole circuit. In a parallel circuit, electrons flow through smaller circuits all coming from the same source. The amperage is different in each circuit based on the resistance offered. The one wire running to all the smaller circuits has higher current than any of the small offset circuits. Removing one thing will not affect the other smaller circuits as electrons can still flow. Current will be affected, of course.
