Accessories

Transformer Accessories
Transformer accessories are pieces of equipment that support the safe, efficient and long-lasting operation of a transformer, whilst assisting in the monitoring of operating conditions and the early detection of potential faults. The accessories to be used are determined according to the transformer’s power rating, type, operating conditions and customer requirements.

Hermetic Protection Relay
The hermetic protection relay is a multi-functional protection device used to ensure safe operation in hermetic-type transformers. It monitors conditions such as excessive temperature, pressure rise, low oil level and gas accumulation that may occur within the transformer, and ensures that the protection system is activated when necessary.

It features warning and trip (trigger) contacts for each protection function. The hermetic protection relay can be used in transformers with a power rating of 630 kVA and above.

Buchholz Relay
The Buchholz relay is a crucial piece of protective equipment installed in the connecting pipe between the main tank and the expansion tank of transformers fitted with an oil expansion tank.

It detects gas accumulation and oil movement resulting from electrical faults within the transformer or deterioration of insulation materials, and sends a signal to the protection system. Operating via two separate contacts—a warning contact and a trip contact—it helps to detect potential faults at an early stage.

Contact-Type Oil Temperature Thermometer
The contact-type oil temperature thermometer enables continuous monitoring of the transformer oil temperature and provides an alarm should the specified limit values be exceeded.

Oil temperatures between 0 and 120 °C can be monitored via the thermometer. Thanks to two adjustable contacts, warning and trip signals are triggered at pre-set temperature levels, helping to protect the transformer against overheating.

Pressure Relief Valve
The pressure relief valve supports the safety of the transformer tank by ensuring that sudden increases in internal pressure, which may occur during a fault—particularly in hermetic transformers—are released in a controlled manner.

The valve can be set to a specific pressure value appropriate to the transformer’s operating conditions. It can be used with either contact or non-contact options, depending on requirements.

Oil Level Indicator
Oil level indicators enable the level of insulating oil inside the transformer to be monitored easily and reliably. By helping to track changes in the oil level, they make it easier to detect potential leaks or drops in level.

Magnetic Oil Level Indicator
A magnetic oil level indicator is a monitoring device that allows the transformer’s oil level to be easily monitored from the outside. It is particularly useful for reliably monitoring the oil level in transformers fitted with expansion tanks.

Dehumidifier
A dehumidifier prevents moisture from entering the transformer from the external environment during its ventilation process