Table of Contents
Why do we need to test the transformer?
The need for transformer testing is to check the functioning of the transformer and to decrease the chance of failure. Mechanical induced failure is due to the deforming of the transformer’s windings that would result in the abrasion or rupturing of its paper insulation.
What do you understand by transformer testing?
The transformer testing can be done to determine the specifications, and performance of an electrical transformer. To meet the specific design and specifications, transformer testing should be done during the manufacturing process.
What are the advantage of transformer maintenance and tests?
A power transformer maintenance and testing program includes the following benefits: Increased safety, problems are detected before they are a hazard. Increased equipment efficiency, conditions related to transformer losses can be corrected. Reduced expenses, repair work can be properly scheduled.
What are the testing of power transformer?
Power transformer tests:
- Measurement of Winding Insulation Resistance.
- Winding Resistance Test.
- Voltage Ratio Test.
- Polarity Test.
- No-Load Losses Test.
- Load Losses (Short Circuit) Test.
- Vector Group Test.
- Capacitance and tan δ Test.
How do you inspect a transformer?
1. Visual and Mechanical Inspection
- Compare equipment nameplate datawith drawings and specifications.
- Inspect physical and mechanical condition.
- Verify correct connection of transformers with system requirements.
- Verify that adequate clearances exist between primary and secondary circuit wiring.
How often should transformers be tested?
every 6 months
Your electrical transformer needs to be checked every 6 months for IFT, DDA, flash point, sludge content, acidity, water content and dielectric strength along with how resistant it is to transformer oil.
What are the tests that we perform in potential transformers?
The three Potential Transformer Tests are namely,
- Polarity check,
- Ratio check and.
- Phasing check.
How do potential transformers work?
The potential transformer consists of primary winding with more turns and secondary winding with less number of turns. The high input AC voltage is given to the primary winding (or connected to the high voltage circuit to measure). The lower output voltage is taken across the secondary winding by using a voltmeter.
What is transformer testing and why is it important?
Transformer testing is done for confirming the specifications and performance of an electrical power transformer. The transformer is the main part of an electrical distribution system so if it is not working properly then it will affect the distribution system. So it has to go through numerous testing procedures.
How to perform insulation testing on a current transformer?
Insulation tests on current transformers are usually performed at 1000VDC. Prior to testing, short the primary winding of the CT under test by connecting H1 and H2, then short the secondary winding of the CT under test by connecting X1 and X2-X5. Remove the neutral ground and isolate the CT from any associated burden.
Where are the tests performed on Transformers?
Some of the tests are done at the factory during the manufacturing process. Other tests are done at the site at the time of the transformer installation. The routine tests are performed on all transformers. But type tests are performed on each unique design.
What are the pre‐commissioning checks and tests of a power transformer?
Various pre‐commissioning checks and tests are performed to ensure the healthiness of the power transformer prior to its energization. Operational checks on the protection system.