IMAGES OF VOLTAGE TRANSFORMERS INCLUDING TYPES AN DEFINITIONS

IMAGES OF VOLTAGE TRANSFORMERS INCLUDING TYPES AN DEFINITIONS

Images and Illustration of a typical voltage transformer for medium and high voltage level.

A voltage transformer or potential transformer is an instrument transformer intended to have its primary winding connected in shunt with a power supply circuit, the voltage of which is to be measured or controlled.

A cascade-type voltage transformer is a single high-voltage line terminal voltage transformer with the primary winding distributed on several cores with the cores electromagnetically coupled by coupling windings and the secondary winding on the core at the neutral end of the highvoltage winding. Each core of this type of transformer is insulated from the other cores and is maintained at a fixed potential with respect to ground and the line-to-ground voltage.

A double-secondary voltage transformer is one that has two secondary windings on the same magnetic circuit insulated from each other and the primary. Either or both of the secondary windings may be used for measurements or control.

A grounded-neutral, terminal-type voltage transformer is one that has the neutral end of the high-voltage winding connected to the case or mounting base.

An insulated-neutral, terminal voltage transformer is one that has the neutral end of the high-voltage winding insulated from the case or base and connected to a terminal that provides insulation for a lower voltage insulation class than required for the rated insulation class of the transformer.

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PARTS OF A POWER TRANSFORMER

What are the name of the basic parts of a Power Transformer? We can not deny the fact that only a handful of electrical engineering students are presently familiar with power transformers especially on what it looks like. Unlike a transformer we found in our homes, a power transformer’s appearance and construction is somewhat more complicated. It is not just a simple winding with a primary and secondary terminal although basically any transformer has one. The function that a power transformer plays in an electrical system is very important that an electric utility can not afford to loss it during its operation. Our discussion here will focus more on the basic parts and functions of a power transformer that are usually tangible whenever you go to a substation . Although not all power transformers are identical, nonetheless they all have the following listed parts in which the way of construction may differ.

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ELECTRIC MOTOR FRAME SIZE STANDARD SPECIFICATIONS

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ELECTRIC MOTOR NAMEPLATE SPECIFICATIONS

How do we interpret an electric motor nameplate? Motor standards are established on a country by country basis.Fortunately though, the standards can be grouped into two major categories: NEMA and IEC (and its derivatives). In North America, the National Electric Manufacturers Association (NEMA) sets motor standards, including what should go on the nameplate (NEMA Standard MG 1-10.40 "Nameplate Marking for Medium Single-Phase and Polyphase Induction Motors").

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