Instrument Transformers Current transformer and voltage transformer measuring instrument transformers are designed to operate at low current and low voltage. Safety is also a reason for not connecting test instruments to sources operating at high voltage. An instrument transformer reduces high voltages and currents to safe values. Instrument transformers performs two functions. It serves as … Read more
Basic Transformer Construction A transformer consists of two coils mounted in fixed positions relative to each other. One coil is supplied by an alternating current. As the current alternates, the magnetic field it produces also alternates. This alternating field induces an alternating current in the second coil, which supplies a load. A simple transformer construction consists … Read more
Transformers have high efficiencies, especially the larger sizes operating at 50 to 100% of full load. However, they are not perfect. Some losses occur in all transformers. Transformer losses are divided into two types Copper losses Core losses Copper loss Copper loss is the loss of power caused by the resistance of the copper windings. … Read more
Dry Cell The potential difference between the terminals of a dry cell is about 1.5 volts (abbreviated V), regardless of the size of the cell. The potential difference depends only on the chemicals used in making the cell. The size affects only the length of time required for discharge. Dry Cell Size The larger the … Read more
Measuring Current measuring current on certain troubleshooting jobsis required. You will need to know how much value of current is flowing in part of a circuit. Measuring the current establishes part of the basis for analyzing the circuit which can lead you to the cause of the problem. To measure the current, you use an … Read more
Electric Current Many materials have free electrons. These electrons are not bound tightly to the atoms. They are free to move from one atom to another. When large numbers of these electrons move in one direction, the result is called an electric current. Electric Current in Metals In metals-for example, copper-the free electrons can move … Read more
Electrical Terms Understanding of electrical terms is compulsory for engineers. As you study electricity in your engineering program, and as you work with electricity in the power plants, industrial plants, you will hear, read, and use various electrical terms. These terms have very exact meanings. You must know what each one means if you are … Read more
Definition of Static Electricity Static electricity is electricity that does not move. The word “static” comes from the Greek word “statikos”, meaning the act of making something stand still. Static electricity consists of electrical charges that remain unmoving on an object. Static electricity is usually generated by the physical contact and separation of different kinds … Read more