When an internal fault occurs in an oil-filled transformer not protected by the TRANSFORMER PROTECTOR (TP), the electric arc produces a large amount of explosive gases. Those gases quickly create an overpressure that leads to transformer tank explosion. The tank cover is often damaged, opened, and the explosive gases being in contact with air (oxygen) causes a fire. Unfortunately, the conservator oil generates a transformer tank overflow, which causes the fire to spread on the ground to the surrounding equipment and afterwards to the whole plant.
The CONSERVATOR SHUTTER function is to isolate the conservator tank when an excessive flow is detected. This prevents the conservator oil from feeding the transformer fire.
The CONSERVATOR SHUTTER is important for transformer safety and recommended by organizations such as IEEE, CIGRE, etc.
A properly designed CONSERVATOR SHUTTER must:
- Close to prevent flow from the conservator to the main tank when a catastrophic tank rupture occurs
- Stay open to allow flow due to contraction of the oil volume during normal power variations and weather changes
The TPC CONSERVATOR SHUTTER, TL type, is:
- The sole TP shutter available in the market that has been tested under transformer rupture of insulation, a live test certificate is available on request
- Self-contained, wholly mechanical
- Ready to operate without commissioning setting
- Including testing lever for easy operation
- Equipped with an integrated magnetic switch; then, when the TL closes, an alarm is sent to the plant control room
The TL CONSERVATOR SHUTTER is also very often used by electric utilities located in earthquake and hurricane areas, where movement causes transformer conservator pipes to rupture or leak.
- TL24, for 2-inch piping (DN50)
- TL34, for 3-inch piping (DN80)