4) Calculate the resistance using Ohm’s Law: Resistance = Voltage / Current. 5) Now to get stall current at the rated motor voltage, use Ohm’s Law again: Stall Current = Rated Voltage / Resistance.
What is stall current of a motor?
Stall current is the maximum current drawn1, when the motor is applying its maximum torque, either because it is being prevented from moving entirely or because it can no longer accelerate given the load it is under.
How do you calculate current in a DC motor?
Calculate the field current for the motor using the formula I = V/R where I is the field current. As an example, assume V is 40 volts and R is 500 ohms: I = 40/500 = 0.08 amps.
What is 120 in motor speed formula?
The equation for calculating synchronous speed is: S = 120 f/P speed = constant (120) times frequency of power source (60 Hz) divided by number of poles used in the motor (P).
What is are the condition S that will make the motor stall?
If torque required by the load exceeds the amount of torque produced, the motor will stall. The motor will draw locked rotor current ratings, which are, on average, 3-6 times full load current. This will lead to excessive heating of the windings and will cause the insulation to be damaged.
Does stalling an electric motor damage it?
However, electric motors left in a stalled condition are prone to overheating and possible damage since the current flowing is maximum under these conditions. The maximum torque an electric motor can produce in the long term when stalled without causing damage is called the maximum continuous stall torque.
What causes an induction motor to stall?
If an induction motor is stalling, there will usually be a vibration and even a buzzing or humming sound. Mechanical stalling is typically the result of the driven device being unable to move. Electrical stalling, especially in a 3 phase induction motor, typically is result of a single phase or missing phase condition.
How do you calculate the power of a motor?
Power = (Force x Distance) / Time
For electric motors, power or horsepower can be calculated from the torque and speed. For example, if you have a motor rated for 3,000 RPM and 6 in-lbf then the horsepower is calculated below.