Skip to main content

BASIC PARTS OF A SINGLE-PHASE DISTRIBUTION TRANSFORMER AS SEEN BY THE NAKED EYE

BASIC PARTS OF A SINGLE-PHASE DISTRIBUTION TRANSFORMER AS SEEN BY THE NAKED EYEBasic parts of a distribution transformer that can be virtually seen.

Distribution transformers constructions are relatively less complicated compared to a substation transformer. Although both have exactly similar principle of operation and that is to transform voltage from a higher level to a smaller voltage level, their basic parts differs significantly.

Distribution transformers are basically categorized into two; pad-mounted and pole-mounted distribution transformers. Pad-mounted distribution transformers are also known as mini-substation transformers. Comparing pad-mounted to pole-mounted, pole-mounted distribution transformers are the type of transformer that we usually see especially in developing countries.

Found below are the basic parts of a single-phase pole-mounted distribution transformers we usually see;

Transformer tank – this encloses the oil insulation and winding of the transformer. Typical transformer tanks can either be in cylindrical or rectangular form. The entire assembly is baked to cure the resin then submerged in a large (usually gray) powder coated steel tank which is then filled with high purity mineral oil, which is inert and non-conductive. The tank is temporarily depressurized to remove any remaining moisture that would cause arcing.

Tank Cover – the tank cover includes rubber gasket to securely seal the transformer winding from the weather. Attached also to the tank cover are the primary bushings of the distribution transformer.

Primary bushings/terminals – the primary terminals are attached to the high voltage side of the transformer. Primary bushings can be in single or double bushing depending whether it is for line-to-neutral or line-to-line application. The basic construction of a primary bushing is made up of the conducting terminals and the ceramic insulator.

Secondary bushings/terminals – the secondary terminals are found perpendicular to the body of the distribution transformer. Some distribution transformers have two, three or four terminals depending on the preference of the user.

Cooling fins/radiators – Cooling fins serves as a heat dissipation device intended to reduce the temperature rise of the liquid insulation (oil). The mineral oil helps dissipate heat and protects the transformer from moisture, which will float on the surface of the oil.

Transformer KVA rating – is the visual indicator of the kva capacity of the distribution transformer designed to be seen from a far.

Pressure Relief Device – although not found in the illustration, pressure relief devices are usually found in a typical distribution transformer intended to release pressure build up once specified limit is reached.

Body Grounding Terminal – this is to have a physical ground connection from the transformer tank for safety purposes.

Comments

  1. Distribution transformers normally have ratings less than 200 kVA,[2] although some national standards can allow for units up to 5000 kVA to be described as distribution transformers.
    Power transformers in India | Transformer manufacturer in India

    ReplyDelete
  2. Good one, thanks for the post. It contains useful information regarding Distribution Transformer.

    ReplyDelete
  3. Thanks for sharing your experience with us. Are you trying to find out what are the benefits of three-phase transformers?Look no further; MACROPLAST Transformers' blog provides a thorough explanation of benefits of three-phase transformers. In this field, we have years of experience and knowledge. We go over every advantage of three-phase transformers.

    ReplyDelete

Post a Comment

Popular posts from this blog

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.

ELECTRIC MOTOR FRAME SIZE STANDARD SPECIFICATIONS

ELECTRIC MOTOR FRAME SIZE STANDARD SPECIFICATIONS How is electric motor frame size being specified? Motor frame dimensions have been standardized with a uniform frame size numbering system. This system was developed by NEMA and specific frame sizes have been assigned to standard motor ratings based on enclosure, horsepower and speed. The current standardized frames for integral horsepower induction motors ranges from 143T to 445T. These standards cover most motors in the range of one through two hundred horsepower. Typical example of where you can locate the frame is shown in Fig 1.2.D – Frame No. The numbers used to designate frame sizes have specific meanings based on the physical size of the motor. Some digits are related to the motor shaft height and the remaining digit or digits relate to the length of the motor. The rerate, or frame size reduction programs were brought about by advancements in motor technology relating mainly to higher temperature ratings of insulating mate

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").