Phenix Construction Technologies Electrician Interview Questions and Answers

Dial starter connection diagrams are used to show the wiring connections for a dial starter.

• The diagrams typically show the power supply connections, control circuit connections, and motor connections.

• The power supply connections include the incoming power and the power going to the motor.

• The control circuit connections include the start and stop buttons, overload protection, and any other control devices.

• The motor con...read more

Star delta connection is a method of connecting three-phase electrical motors.

• Used to reduce starting current and torque

• Star connection for starting, delta connection for running

• Commonly used in industrial applications

• Requires a special motor starter

• Reduces stress on motor windings

LT stands for Low Tension, CT stands for Current Transformer, HT stands for High Tension.

• LT - Low Tension refers to electrical systems operating at voltages below 1,000 volts.

• CT - Current Transformer is a type of instrument transformer used to measure alternating current.

• HT - High Tension refers to electrical systems operating at voltages above 1,000 volts.

• Examples: LT cables, CT meters, HT transformers.

An air compressor works by converting power into potential energy stored in compressed air.

• Check the oil level and drain the water from the tank before use

• Connect the air hose to the compressor and the tool you want to use

• Turn on the compressor and wait for it to build pressure

• Adjust the pressure regulator to the desired level

• Turn off the compressor and disconnect the air hose when finished

MIG/MAG welding machine is a type of welding equipment that uses a consumable wire electrode to create an electric arc for welding.

• MIG stands for Metal Inert Gas while MAG stands for Metal Active Gas.

• The machine uses a shielding gas to protect the weld from atmospheric contamination.

• It is commonly used in automotive and manufacturing industries.

• MIG/MAG welding is known for its speed and versatility.

• The machine can be u...read more

Motor HP can be calculated using the formula: HP = (Torque x RPM) / 5252

• Determine the torque and RPM of the motor

• Use the formula: HP = (Torque x RPM) / 5252

• For example, if a motor has a torque of 50 lb-ft and an RPM of 3,000, the HP would be (50 x 3000) / 5252 = 28.6 HP

Chock, Ignitor, and Capacitor are electrical components used in various applications.

• A chock is an inductor used to limit the flow of current in an electrical circuit.

• An ignitor is a device used to ignite fuel in combustion engines or lamps.

• A capacitor is an electrical component used to store energy in an electric field.

• All three components are commonly used in lighting systems, power supplies, and electronic devices.

Power factor is the ratio of real power to apparent power in an AC circuit.

• Power factor can be improved by using capacitors or inductors in the circuit.

• A high power factor means more efficient use of electricity.

• Low power factor can result in penalties from utility companies.

• Power factor correction is important in industrial and commercial settings.

• Power factor is measured on a scale of 0 to 1, with 1 being ideal.

KVARH and KVA can be calculated using different formulas based on the type of circuit and load.

• For single-phase circuits, KVA = voltage x current x power factor

• For three-phase circuits, KVA = voltage x current x 1.732 x power factor

• KVARH is calculated by integrating the reactive power over time

• KVARH = (KVAR x hours of operation) / 1000

• KVAR can be calculated using the Pythagorean theorem: KVAR = sqrt(KVA^2 - KW^2)