Experiment - 4
To measure the dielectric strength of transformer oil.
- Portable oil testing set-220/250 V
- HV transformer-50 kV/250 V
- Gap setting gauges -0.15711 width
- Place the High Voltage transformer unit about 7” away from the central unit.
- The central unit is connected to supply voltage taking care that the earth connections are effective.
- The multiple point control switch is set at its lowest tapping.
- The push button on control unit is pressed firmly for at least 5 seconds. Note that no Breakdown to occurs, in which case button should be released at once without delay. Break down is indicated by a continuous discharge across the gap, bubbling of oil in the cell and meter indicating a sudden voltage drop.