Distribution transformers typically use various accessories to ensure their proper functioning and to enhance their performance. Some common accessories used in distribution transformers include:
- Bushing
Bushings are used to provide electrical insulation and support for the conductors that connect the transformer to the external circuit.
- Tap changer
Tap changers are devices that allow the adjustment of the transformer's turns ratio by changing the tapping point on the winding. They are used to regulate the output voltage and compensate for voltage fluctuations.
- Cooling system
Distribution transformers may incorporate different cooling systems, such as oil-immersed cooling or forced air cooling, to dissipate heat generated during operation and maintain optimal temperature levels.
- Breather
A breather is a device that helps maintain the dryness of the air inside the transformer tank by preventing moisture from entering. It contains a desiccant material that absorbs moisture from the incoming air.
- Buchholz relay
Buchholz relay is a protective device installed in oil-filled transformers. It detects and provides an alarm or trip signal in case of internal faults such as an electrical arc or gas formation in the transformer's oil.
- Pressure relief device
This device is used to relieve excess pressure inside the transformer tank in the event of a fault or abnormal condition. It helps prevent damage to the tank and ensures the safety of the transformer.
- Winding temperature indicator (WTI) and oil temperature indicator (OTI)
These indicators are used to monitor the temperature of the transformer's windings and oil. They provide important information for maintaining the transformer's temperature within safe limits.
- Pressure gauge
A pressure gauge is used to measure the pressure inside the transformer tank. It helps monitor the internal pressure and detect any abnormal conditions.
- Oil conservator
An oil conservator is a reservoir that allows the expansion and contraction of the transformer oil with temperature variations. It helps maintain a constant oil level and prevents the contact between oil and air.
- Insulation and grounding accessories
Various insulation materials, such as insulating bushings, insulating paper, and insulating tape, are used to provide electrical insulation and prevent current leakage. Grounding accessories like grounding leads and grounding clamps are used to establish a safe electrical connection to the ground.
These are some of the commonly used accessories in distribution transformers. The specific accessories used can vary depending on the transformer's design, size, and application.
