Ques:- WHY THE SYNCHRORONOUS MOTOR IS NOT SELF STARTING, AND WHY THE STATOR AND ROTOR IS COUPLED?
Asked In :-
Ethiopian Maritime, aker solutions,
Ques:- How many earthing should give for transformer body and nuetral
Asked In :-
Right Answer:
Typically, one earthing connection should be provided for the transformer body and one for the neutral.
Typically, one earthing connection should be provided for the transformer body and one for the neutral.
Ques:- In dc shunt generator field is open in running condition what will happen?
Asked In :-
UK Civil Aviation Authority, smurfit kappa, eaton, united launch alliance (ula), sgc, ethiopian electric power corp., delta state hospital management board,
Ques:- How to estimate the breaker capacity of breaker,please give the one example( 6.6 kv breaker,800a)?????
Ques:- If transformer winding burn on dc supply then why not alternator rotor winding
Asked In :-
Right Answer:
A transformer winding burns on DC supply because it creates continuous current, leading to overheating. In contrast, an alternator rotor winding is designed to operate with AC, and when supplied with DC, it does not generate the same continuous magnetic field or overheating effect as a transformer, allowing it to withstand DC supply without burning out immediately.
A transformer winding burns on DC supply because it creates continuous current, leading to overheating. In contrast, an alternator rotor winding is designed to operate with AC, and when supplied with DC, it does not generate the same continuous magnetic field or overheating effect as a transformer, allowing it to withstand DC supply without burning out immediately.
Ques:- Describe one of your memorable day?how is education useful for any body?
Asked In :-
Eppendorf,
Right Answer:
One of my memorable days was when I successfully led a team project that improved the quality of our product, resulting in fewer defects and higher customer satisfaction. Education is useful for anyone as it provides knowledge and skills that help in personal and professional growth, enabling individuals to make informed decisions and solve problems effectively.
One of my memorable days was when I successfully led a team project that improved the quality of our product, resulting in fewer defects and higher customer satisfaction. Education is useful for anyone as it provides knowledge and skills that help in personal and professional growth, enabling individuals to make informed decisions and solve problems effectively.
Ques:- PID controller is used for which type of compensation??a) lead comp. b) lag com. c) lead lag com.
Asked In :-
Commercial Vehicle, marquardt india pvt. ltd,
Ques:- What is Metering theory?
Right Answer:
Metering theory refers to the principles and methods used to measure electrical quantities such as voltage, current, power, and energy in electrical systems. It involves the use of meters and instruments to accurately quantify these parameters for monitoring, billing, and analysis purposes.
Metering theory refers to the principles and methods used to measure electrical quantities such as voltage, current, power, and energy in electrical systems. It involves the use of meters and instruments to accurately quantify these parameters for monitoring, billing, and analysis purposes.
Ques:- When we give supply to a transformer 11 kv and we get 415v from it, so when we give supply to same transformer 415v on ht side what we get?and When we gives supply to any transformer to L.T. side 415v or 220v What supply is on H.T. side?
Asked In :-
Ques:- How to check the insulation for motor using megger?
Asked In :-
Right Answer:
To check the insulation of a motor using a megger, follow these steps:
1. **Disconnect Power**: Ensure the motor is completely disconnected from the power supply.
2. **Prepare the Megger**: Set the megger to the appropriate voltage rating (usually 500V or 1000V).
3. **Connect Leads**: Connect one lead of the megger to the motor's winding terminal and the other lead to the motor's frame (ground).
4. **Take Reading**: Press the test button to apply the voltage and read the insulation resistance value on the megger display.
5. **Evaluate Results**: A resistance value above 1 MΩ is generally acceptable; lower values indicate potential insulation failure.
Always follow safety protocols during testing.
To check the insulation of a motor using a megger, follow these steps:
1. **Disconnect Power**: Ensure the motor is completely disconnected from the power supply.
2. **Prepare the Megger**: Set the megger to the appropriate voltage rating (usually 500V or 1000V).
3. **Connect Leads**: Connect one lead of the megger to the motor's winding terminal and the other lead to the motor's frame (ground).
4. **Take Reading**: Press the test button to apply the voltage and read the insulation resistance value on the megger display.
5. **Evaluate Results**: A resistance value above 1 MΩ is generally acceptable; lower values indicate potential insulation failure.
Always follow safety protocols during testing.
Ques:- What is earthed and inearthed cable or system?
Asked In :-
Right Answer:
Earthed systems have a direct connection to the ground, providing a path for fault currents to safely dissipate, which enhances safety. In contrast, unearthed systems do not have this direct connection, meaning they can operate without grounding, but they may pose higher risks in fault conditions.
Earthed systems have a direct connection to the ground, providing a path for fault currents to safely dissipate, which enhances safety. In contrast, unearthed systems do not have this direct connection, meaning they can operate without grounding, but they may pose higher risks in fault conditions.
Ques:- What is negative range in transmeter?
Ques:- Why only three phase power generation are load are used
Asked In :-
TC Energy, UOP Honeywell,
Right Answer:
Three-phase power generation is used because it provides a more efficient and stable power supply, allows for smaller and lighter conductors, and enables the use of smaller and more efficient motors compared to single-phase systems.
Three-phase power generation is used because it provides a more efficient and stable power supply, allows for smaller and lighter conductors, and enables the use of smaller and more efficient motors compared to single-phase systems.
Ques:- What is the difference between arc and spark
Asked In :-
starfish medical,
Right Answer:
An arc is a continuous discharge of electricity between two conductive points, producing a sustained plasma, while a spark is a brief, high-voltage discharge that occurs when there is a sudden breakdown of insulation, creating a short-lived electrical connection.
An arc is a continuous discharge of electricity between two conductive points, producing a sustained plasma, while a spark is a brief, high-voltage discharge that occurs when there is a sudden breakdown of insulation, creating a short-lived electrical connection.
Ques:- What is thermal relay and how it is works in transformer please explain
Asked In :-
liberty utilities, wurth electronics midcom,
Right Answer:
A thermal relay is a protective device that detects overheating in electrical equipment, such as transformers. It works by using a bimetallic strip that bends when heated due to excessive current flow. When the temperature exceeds a set limit, the bending strip triggers a switch to open the circuit, disconnecting the transformer and preventing damage from overheating.
A thermal relay is a protective device that detects overheating in electrical equipment, such as transformers. It works by using a bimetallic strip that bends when heated due to excessive current flow. When the temperature exceeds a set limit, the bending strip triggers a switch to open the circuit, disconnecting the transformer and preventing damage from overheating.
Ques:- Why we choose 400kv,220kv,132kv,66kv,33kv transmission voltages for transmitting power. Why not other voltage levels.
Asked In :-
Right Answer:
We choose 400kV, 220kV, 132kV, 66kV, and 33kV transmission voltages because these levels are optimal for minimizing power losses, ensuring efficient transmission over long distances, and balancing insulation requirements and equipment costs. Higher voltages reduce current, which decreases resistive losses, while these specific levels are standardized for compatibility with existing infrastructure and equipment.
We choose 400kV, 220kV, 132kV, 66kV, and 33kV transmission voltages because these levels are optimal for minimizing power losses, ensuring efficient transmission over long distances, and balancing insulation requirements and equipment costs. Higher voltages reduce current, which decreases resistive losses, while these specific levels are standardized for compatibility with existing infrastructure and equipment.
Ques:- What is the Difference Between MCCB & ACB & VCB
Asked In :-
Right Answer:
MCCB (Molded Case Circuit Breaker) is used for medium voltage applications and provides overload and short-circuit protection. ACB (Air Circuit Breaker) is used for high current applications and can handle larger loads, providing protection against overloads and short circuits. VCB (Vacuum Circuit Breaker) is used for high voltage applications and operates by interrupting the circuit in a vacuum, offering fast operation and minimal maintenance.
MCCB (Molded Case Circuit Breaker) is used for medium voltage applications and provides overload and short-circuit protection. ACB (Air Circuit Breaker) is used for high current applications and can handle larger loads, providing protection against overloads and short circuits. VCB (Vacuum Circuit Breaker) is used for high voltage applications and operates by interrupting the circuit in a vacuum, offering fast operation and minimal maintenance.
Ques:- What are the needs of electrical earthing…. other than protection?
Asked In :-
yorkshire water, secure meters,
Ques:- How do we know the LT or HT panel trip by some problem which indication will show
Asked In :-
taiyo yuden,
Right Answer:
To determine if an LT (Low Tension) or HT (High Tension) panel has tripped due to a problem, you can check the following indications:
1. **Tripping Indicator Light**: A red light or indicator on the panel will show that the circuit has tripped.
2. **Circuit Breaker Position**: The circuit breaker will be in the 'OFF' position or in a tripped state.
3. **Alarm or Buzzer**: An audible alarm or buzzer may sound to indicate a fault.
4. **Fault Display**: Some panels have a digital display that shows fault codes or messages indicating the type of issue.
These indicators help identify the cause of the trip.
To determine if an LT (Low Tension) or HT (High Tension) panel has tripped due to a problem, you can check the following indications:
1. **Tripping Indicator Light**: A red light or indicator on the panel will show that the circuit has tripped.
2. **Circuit Breaker Position**: The circuit breaker will be in the 'OFF' position or in a tripped state.
3. **Alarm or Buzzer**: An audible alarm or buzzer may sound to indicate a fault.
4. **Fault Display**: Some panels have a digital display that shows fault codes or messages indicating the type of issue.
These indicators help identify the cause of the trip.
Ques:- If 2500 KVA TRANSFORMER CAPACITY.33KV INCOMING HOW ARE AMPEAR PRIMERY SAID
Asked In :-
dyson, liberty utilities,
Right Answer:
To calculate the primary amperage of a 2500 KVA transformer with a 33 kV incoming voltage, use the formula:
Amperes (A) = KVA × 1000 / Voltage (V)
So,
Amperes = 2500 × 1000 / 33000 = 75.76 A
The primary amperage is approximately 75.76 A.
To calculate the primary amperage of a 2500 KVA transformer with a 33 kV incoming voltage, use the formula:
Amperes (A) = KVA × 1000 / Voltage (V)
So,
Amperes = 2500 × 1000 / 33000 = 75.76 A
The primary amperage is approximately 75.76 A.
