National Petroleum Construction Company Electrical Technician Interview Questions and Answers

Types of transformers include power transformers, distribution transformers, autotransformers, isolation transformers, and instrument transformers.

• Power transformers are used to step up or step down voltage in power transmission systems.

• Distribution transformers are used to step down voltage for distribution to consumers.

• Autotransformers have a single winding and are used for voltage regulation.

• Isolation transformers p...read more

IR test stands for Insulation Resistance test which is used to measure the resistance of insulation material.

• IR test is used to check the quality of insulation material used in electrical equipment.

• It helps to detect any insulation failure or breakdown in the equipment.

• The test involves applying a high voltage to the insulation material and measuring the current flowing through it.

• The measured resistance value is compa...read more

CT stands for Current Transformer, a device used to measure electrical current.

• CT is a type of transformer that steps down high current to a lower, measurable level.

• It is commonly used in power systems to measure current flowing through a circuit.

• CTs are also used for protection purposes, such as detecting overcurrent or short circuits.

• CTs can be either solid-core or split-core, with the latter being easier to install.

• ...read more