We are having following Testing Facility for Transformer
Dielectric Response Analyzer(DIRANA)Test
Dielectric Response Analyzer (DIRANA) Test on Transformer Winding (To determine the moisture content in oil-paper insulations of Winding by Direct Measurement). This is the most advanced method of determining the moisture content in oil-paper insulations of Transformer Winding. The DIRANA reduces the required measurement time to 50%, as the device uses a combination of the time and frequency range method (Polarization Depolarization Current [PDC] and Frequency Domain Spectroscopy [FDS]).
|1||< 10 kHz||Main Core; Bulk Winding (Inductance)|
|2||10 kHz to 150 kHz||Bulk Component Shunt Impedances|
|3||150 kHz to 400 kHz||Main Windings|
|4||400 kHz to ~1 MHz||Main windings, Tap windings etc|
CAPACITANCE AND TAN DELTA TEST
In This Test Insulation power factor or dissipation factor (Tan delta) and Capacitance measurement of bushing provide an indication of the quality and soundness of the transformer winding/winding of alternator motor and insulation in the bushing. In this Test voltage upto 10kV is applied to Bushing and Winding. There are two type mode of measured in this method UST & GST Mode.
Eltel Make Tan-delta Testing Kit
In this test, voltage upto 10kV is Applied to Bushing and Winding.There are Two type mode of measured in this method UST & GST Mode.
Insulation Resistance Test(5000 Volts)
Insulation resistance (IR) measurement is the simplest and most widely used test to check the soundness of transformer insulation. This test reveals the condition of insulation (i.e.Degree of dryness of paper insulation), presence of any foreign contaminants in oil and also any gross defect inside the transformer (like failure to remove the temporary transportation bracket on the live portion of tap-changer part).
Winding Resistance Test (25 amps)
Transformer winding resistance are measured in the field in order to check for any abnormalities due to loose connections, broken strands and high contact resistance in tap changers as a pre-commissioning checks and compare the measured values with factory test values.
Voltage Ratio Test
To determine the turns ratio of transformer, Turns Ratio: The Turns Ratio of a transformer is the ratio of the number of turns in a higher voltage winding to that in a lower voltage winding. Transformer turns ratio (TTR) meter available in convenient portable form. They have a hand crank power supply, with the voltages commonly used being very low, such as 12-120 V and 50-60 Hz.
There is need for testing and monitoring the electrical network’s arresters, in order to verify their good condition and their ability to effectively protect the lines. The most common method used, is the measurement of the arresters’ total leakage current (with the isolation of the resistive part), which is an indicator of the arrester’s condition, since every change, deterioration or damage leads to an increase of the resistive leakage current.
VLF cable testing is a technique for testing of medium and high voltage (MV and HV) cables. VLF systems are advantageous in that they can be manufactured to be small and lightweight; making them useful – especially for field testing where transport and space can be issues. Traditionally DC voltage sources have been used for field testing of cables but these sources have been shown to be ineffective at withstand testing for most kinds of damage. DC diagnostics have also been shown to yield ambiguous results and are generally considered and ineffective for MV and HV power cables. Because the inherent capacitance of a power cable needs to be charged when energized.