Power transformers are stationary electrical machines that transfer power from one circuit to another, usually from a transmission line to the consumer, without changing the frequency. As transformers do not have any moving parts, they are considered stationary machines, and they operate with a mutual induction system using an A/C supply. The power transformer functions better when a daily servicing is done on it such as monitoring the oil levels of Magnetic Oil Gauge( MOG) of the main tank and conservator tank, the silica gel should be replaced when the color changes to pink and If there is any leakage detected, it is advised to seal it.

Power transformers boost supply voltage to lower power loss, and then decrease them at the load centers for distribution purposes. This piece of equipment is essential for both homes and businesses because it makes using electrical gadgets safer. As a result of this, power transformers are the most costly and essential piece of equipment within an electrical substation, making it quite important to perform various maintenance/ servicing activities to ensure the transformer maintains a high level of performance and a long functional life.

The main purpose of maintenance of the transformer is to ensure the internal and external parts of the transformer and accessories are in good condition, efficient and able to operate safely. Another essential purpose is to maintain a historical record of the condition of the transformer.

We will take a deeper look into the ideal methods for power transformer servicing ,learn more below;

Power Transformer ABB 200KVA 33.0/0.415KV

The Steps involved in servicing a power generator

There are two main groups of power transformer servicing; the unscheduled servicing which is based on an emergency/reactionary method of operation. In other words, service the machinery only when it malfunctions and then the routine basis which entails the preventive, predictive, and corrective servicing. This servicing process basically involves:

1. Daily Basis Testing and Checking for Power Transformers

The following tests should be performed on your transformer every day:

• To ensure that the oil is filled to the correct level, it is important to regularly check the MOG (Magnetic Oil Gauge) levels of the main tank and conservator tank.
• If the silica gel turns pink, replace it.
• Finally if any leakages are detected, seal them.

2.Power Transformer checks on a Monthly Basis

• To ensure that the oil level in the oil cap doesn't go below a fixed level, it must be checked every month.
• To guarantee proper breathing action at all times, keep the breathing holes in the silica gel breather clean.
• Make sure the oil is filled to the proper level if your electrical transformer has an oil filling bushing.

3.Power Transformer servicing and checks on a Half Yearly Basis

Every six months, you should inspect your electrical transformer to determine its IFT, DDA, flash point, sludge content, acidity, water content, dielectric strength, and oil resistance. A yearly inspection is required of the air fans, oil pumps, and other components used to cool a transformer and control circuit.

• Make sure to use delicate cotton cloths solely to clean all the electrical transformer's bushings.
• Every year, the condition of the oil should be properly checked. To do that, take a sample of oil from the drain valve and measure the moisture content (PPM) and dielectric strength (BDV). The oil needs to be replaced if the PPM value is high and the BDV value is low.
• Every year, make sure to thoroughly clean the insides of each marshalling box. Verify that the heaters for the space and the lighting are operating properly. Also the terminal connections of the control and relay wire need to be tightened.
• A suitable cleaning agent must be used to clean all the control switches, alarms, and relays, as well as the circuits that power them.
• Check all the pockets for the Winding Temperature Indicator and Oil Temperature Indicator to see if they have the required amount of oil, and top it off if necessary.
• Annual inspections are required to ensure that the Buchholz and Press Release Device relays are operating properly.

Finally make sure to measure the resistive value of the earth connection and rizer annually with a clamp on the earth resistance meter.

Power Transformer ABB 200KVA 33.0/0.415KV

Recommended Transformer Oil for Servicing purposes

Transformer oil is an oil with a mineral base, is frequently used in transformers due to its chemical characteristics and dielectric strength. Your transformer uses this oil to cool it down and serve as an insulator. If servicing is not done to replace , the oil will deteriorate over time, increasing the chance of defects and expensive repairs. There are 3 types of transformer oil; The Naphtha, Paraffin and Synthetic transformer oils. They all have different characteristics in terms of oxidation, pour point , solubility as well as absorption qualities and cost. This is why Tikweld welding supplies and services has a variety of goods in this category, as well as knowledgeable staff who can provide guidance and recommend the top option for your specific power transformer. 

Epochem premium Transformer Oil 20L

Frequently Asked Questions

1. Why is power transformer servicing important

Making sure the internal and external portions of the transformer and its accessories are in good shape, efficient, and capable of operating securely is the fundamental goal of power transformer servicing. Keeping a historical record of the transformer's condition is another essential objective of servicing.

2. What is Power Transformer Ratings

The maximum output voltage and current that power transformers can deliver are used to determine their ratings. Power transformer ratings are usually measured in kilovolt amperes (kVA) or megavolt amperes (MVA). It indicates that the transformer's primary and secondary windings are built to resist the kVA or MVA values that are stamped on the transformer nameplate.

The maximum output voltage and current that power transformers can deliver are used to determine their ratings. We'll often read or hear about the volt-ampere (VA) capacity for a given power transformer, which is also a unit used to express the ratings of power transformers and it equals the product of the nominal output voltage and maximum deliverable current.

We have the following formula to calculate a power transformer's rating:

P = UI

P: power transformer ratings

U: nominal output voltage

I: maximum deliverable current

The size of a transformer is determined by the kVA of the load. In many cases, the amount of power needed by the load is equal to the transformer's rating, indicated in VA or kVA. For instance, with unity power factor, a 1KW (1000 Watt) load would require a 1kVA transformer.

Power transformers are categorized according to their kVA rating into;

• Small power transformers: 500 to 7500kVA
• Medium power transformers: 7500kVA to 100MVA
• Large power transformers: above 100MVA

Conclusion

The power transformer is usually the most expensive part of the power supply to repair, if it burns out or suffers damage, therefore servicing is crucial to ensure the longevity of your transformer and professionals have advised to . Follow the routine basis of maintenance which entails the preventive, predictive, and corrective servicing outlined in this content, ensure your device functions smoothly and continues to perform for years to come by Keeping this points in mind

1. Ensure to Maintain transformer protective coating
2. Testing and maintaining transformer insulation systems
3. Inspecting and maintaining transformer auxiliary devices
4. Controlling the transformer's heat and finally
5. Maintaining transformer bushing insulation

For more information on purchase, installation and servicing of power transformers, kindly contact us at Tikweld welding supplies and services.