When no new transmission capacity is added, bringing a previously offline generator online to meet increased demand typically increases the short-circuit MVA (SC MVA) at the bus. This is because the additional generator adds more fault current contribution to the system.
Implications of...
The starting of an induction motor at reduced voltage causes the motor to decrease its starting current and starting torque. If the driven load permits the lower starting torque, the motor can be started using a reduced voltage starting method.
When the motor is started at reduced voltage, the...
When multiple generators are running in parallel, the load distribution among them is dependent on their speed regulation. To ensure the smooth operation of the generators, it is important to check their speed regulation data and maintain a slightly higher incoming frequency than the running...
Too low-resistance of the rheostat used for braking causes high current to flow through the armature and may cause flashover. Yes, you will get more braking torque if the resistance value is low. However, it is important that the sizing of the braking resistor must be done taking into account...
The sizing of the transformer depends on two main factors- the volume of iron and the volume of copper. When you keep flux density lower, you will have to increase the number of turns to get the desired voltage. The increased number of turns causes more copper loss and the size of the...
Yes, it is possible to program a relay for two current settings. You can provide digital inputs to relay for speed 1 & speed 2. The relay will see the current as per the speed input.
The rectifier output has ripples and is used to smoothen the DC inductor or capacitor. When we use a capacitor, the output voltage will be more than the applied RMS ac voltage. This happens when the rectifier output is not connected to the load.
When the current flows through the diodes...
Gross power is the total power generated by the generator, including auxiliary power. The auxiliary power may be 8 to 10 % of the gross power. Therefore, we get net power less than the gross power.
Net power= Gross power - Auxilary power
The motor is an inverter-grade motor or a normal motor. The normal motor when operated with VFD may cause vibration in a band of a certain speed, which may be due to resonance or other reasons. The solution to the problem is to skip that speed range in VFD. Also, check the motor for any...
The incandescent lamp exhibits nonlinear resistance because the resistance changes with temperature. All the heating elements are linear devices and exhibit linear voltage and current characteristics.
Therefore, the rated current of the bulb is in hot condition. The resistance of the bulb is...
RCCB gets trip when there is a ground fault or earth leakage fault. In the case of a short circuit or overcurrent, the MCB will trip. If you want to have both types of protection with one device, install RCBO ( Residual current circuit Breaker)- it will trip in the case of overcurrent, short...
The torque of the DC motor or ac motor is proportional to the magnetic flux and current drawn by the motor. The current produces the magnetic flux which interacts with the main flux and produces the torque.
