#medium voltage transformers

Straton electricals is one of the leading transformer manufacturers in Hyderabad, India. Offers dry type and oil immersed medium voltage instrument transformers such as Outdoor Resin Cast Potential Transformers, Indoor Resin Cast Current Transformers, Medium Voltage Oil Cooled Potential Transformer & Medium Voltage Resin Cast Potential Transformers etc.

Global Medium Voltage Transformers market Research Report Released with growth, latest trends and forecasts till 2025

Summary

A transformer is a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. A varying current in one coil of the transformer produces a varying magnetic field, which in turn induces a varying electromotive force (emf) or “voltage” in a second coil.

The unorganised sector for the global medium voltage transformers manufacture…

Transformers are passive electromechanical components operating on the principle that each electrical field creates a magnetic field. This will isolate two electrical circuits by making the first electrical circuit a non-electrical magnetic field. This second electrical circuit gets the energy from the created magnetic field. Testing a medium voltage transformer ensures that all of its components works properly. Here are the steps to doing it.

Visually inspect the transformer. Overheating happens when the transformer’s windings run at temperatures that are too high, and is a common reason for transformer failure. If you see that the transformer’s exterior has burn marks or is bulging, do not proceed on testing it.

Determine the transformer wiring. A transformer needs to have clear labeling. However, it is best that you get a schematic of the transformer’s manufacture so you will know its limitations. The circuit schematic should be available in the product documentation.

Know the transformer outputs and inputs. The first electrical circuit is connected to the transformer’s primary windings. The voltage supplied to the primary windings should be on both the schematic and the transformer label. The second circuit that gets power from the magnetic field is connected to the transformer’s secondary windings. The voltage coming from the secondary windings has to be on both the schematic and the transformer labeling.

Identify the output filtering. It’s common to attach diodes and capacitors to the transformer’s secondary windings to shade the AC powder coming from the DC power output. This shaping and filtering is not available from the transformer label. This should be shown on the schematic.

Prepare for circuit voltage measurement. Remove the panels and covers as necessary to get access to the circuits containing the transformer. Acquire a digital multimeter so you can take the voltage readings. Digital multimeters are available online and electrical supply stores.

Confirm proper output. Add power input to the circuitry. Use the digital multimeter in AC mode and measure the transformer primary. If it’s less than 80 percent of the expected voltage, the fault might be in the circuity giving the primary power, or the transformer. So, separate the input circuit from the primary. If the input power reaches the expected value, the transformer’s primary may be bad. But if the input power doesn’t reach the expected value, the problem is with the input circuity, not with the transformer.

Measure the secondary output. After determining that there is no shaping or filtering done on the secondary circuitry, use the digital multimeter in AC mode. If there is shaping and filtering, use the DC scale. If there is no expected voltage, either a shaping or filtering component, or the transformer is bad. Separately test the shaping and filtering components. If this doesn’t show problems, the problem lies with the transformer itself.

A step down transformer is a transformer with a secondary voltage that is less than its main voltage. Its primary purpose is to decrease the voltage from the primary winding to the secondary winding. This type of transformer converts low-current, high-voltage power to high-current, low-voltage power. The wire used in the secondary winding is important because of the current increase, and is made with a larger gauge. The primary winding can be made of smaller-gauge wire, since it won’t conduct much current. Read on and learn how to wire a step down transformer.

First, you need to determine what the schematic will look like before you start working with any materials. At the transformer’s lower side is the terminal connection box cover; remove this because only those with high amperages require such enclosure. Next, make sure that you are familiar with the termination identification of step down transformers. H1, H2, H3 and H4 refer to the transformer’s power feed end. This applies to any transformer size.

Cut the wires to length and terminate the feed power wires. With large wire lugs, make sure that you consider the length of the lug as well as the amount of wire that can be installed into the female crimp area. After this, strip the outer insulation of the wires using wire strippers. Place an eye ring over the bare copper wire and crimp the connection device permanently to the wire, using the right-size crimper.

Terminate the high-voltage, high-side of the step down transformer. If you see that the high side terminals are bolts, ensure that you follow any torque requirements listed on the owner’s manual. Do the same with the low-voltage, low-side of the transformer. Remember that these terminals will be identified as X1, X2, X3 and X4. Once again, follow the individual directions stated in the manual for that particular type of transformer you are using.

Also terminate the small control transformer for X1 and X2. X1 will make its way to the control circuit after it passes through a small fuse within the circuit. X2 should only be terminated to the neutral side of the control unit and grounded for safety. In other words, the X2 side of the small control transformer has to be attached to the electrical unit’s grounding system.

Change all covers on the transformer, along with any enclosures that will provide protection from electrical damage. Switch on the feeder power circuit to put the high voltage to the transformer, and turn on the low side safety circuit control. Test for the appropriate voltage you are trying to achieve using a volt meter. Make sure that it matches the voltage indicated on the specifications tag provided by the transformer manufacturer.