0
What else can I help you with?
Why is the starting current high in DC motor?
The starting current is high because when the motor is not rotating no back-emf is generated, leaving the starting current to be determined by the armature resistance, which should be low.
Why you use DOL starter in starting of motor?
because of starting current of induction motor is very high and it damages the insulation of motor
What will be the starting current of a 335hp Sqcage motor on no load?
Across the line starting of a motor can be as high as 300% of the full load amps.
What are components of a DC motor starter that can be affected by a high starting current if it is not limited?
armature
Is it possible to start a motor with starting current of 50 Ampere in a supply of 26 ampere?
Yes. Circuit breakers are designed to accommodate for a short-lived current spike. The motor does not draw high current for long at starting and hence it's possible.
Why the starting torque of a dc series motor is high?
load is heavier so starting torque is requiredAnswerBecause the same current is passing through both the armature and field windings, the torque is proportional to the squareof the current. Since the starting current is alway high (no back emf), the torque will be very high indeed.
Which motor has high starting tourque?
Series motors have the highest starting torque. The torque is proportional to the square of the current, and the starting current is so high it has to be limited by a resistor called a rheostat. Series motos are used mainly on trams and trolley buses.
How much current will draw 75000W 400volt at the starting?
At a steady state (when up and running) Watts = Volts x Amps so you just need to solve the equation 75,000 / 400 = ? However, you add the caveat "starting". If your application involves a motor, for example, the starting current will be higher than the steady state current. One rule of thumb says the starting current may be as high as 6 times the running current. This higher current starts high and then decreases as the motor comes up to speed.
Why the armature rheostat of dc is motor kept at maximum resistance position?
It isn't. It is only kept at maximum resistance when the motor is not running. That is done to limit the starting current.
Why motor does not trips on instantaneous current during starting?
If the protection device is bimetalic type then it takes a few seconds to get heated up before tripping off. In case of other advanced type of protection devices, there could be a preset timer to allow a certain amount of high starting current. In both the cases, the avoidence of tripping during starting is by design, since it is known that the motor takes a high starting current.
Why a 750 kw motor takes 17 amps starting current?
The starting current is high because the motor's rotor winding has very low resistance. It's similar to a transformer with a shorted secondary windings. As the motor accelerates,the back emf increases which resist the flow of current in the rotor winding. Hence,the current drop to the rated full-load value.
What is a disadvantages DOL or direct online starter?
it can not be use for heavy duty motors as well as it requires a high starting current.
