EARTHING OR GROUNDING TRANSFORMERS
(ZIGZAG), ZNYN, YND(OPEN), II0]
Grounding Transformers are designed for providing an artificial neutral point for ungrounded three phase power systems. During the line-to-ground faults, grounding transformers provide an easy path to ground faults to limit the fault currents and transient over voltages.
Grounding transformers normally carry short-circuit ground current until the circuit breaker clears the fault. Therefore, they have short time ratings.
The kVA rating of a earthing transformer depends on the normal line to neutral voltage and the fault current value for a specified time, such as seconds to minutes
- Visual & Dimensional Check
- Measurement of Voltage Ratio
- Measurement of Winding Resistance
- Measurement of Zero Sequence Impedance
- Measurement of No-Load Loss and Current
- Measurement of Short-Circuit Impedance and Load Loss
- Dielectric Tests
- Separate Source AC Withstand Voltage Test
- Induced AC Withstand Voltage Test
- Lightning Impulse Test
- Temperature Rise Test
- Final Check
For special tests, please contact us.