SZ11-35KV Oil-Immersed Substation AC Transformer

Scope of Application

800~31500/35 oil-immersed transformer is suitable for an AC 50Hz system with a rated working voltage of 35kV. It is the main equipment for small and medium-sized substations, ensuring reliable voltage transformation in power distribution networks.

Operating Conditions

Installation Altitude: Up to 1000 meters above sea level
Ambient Temperature: -40°C to +40°C

Structural Features

Iron Core

Core: The core is made of high-permeability cold-rolled silicon steel of magnetic grain orientation, fully processed to provide maximum efficiency. Core Type: Core-type construction – Full oblique joint stacking. Core Column: The core column is of a multi-step circular cross-section. Iron yoke and core sections are of equal cross-sectional dimensions to provide uniform performance.

Windings

The windings are made as coaxial coils. The high voltage windings have taps for the regulation of voltage, to which a tap changer is connected. The tap changer is conveniently mounted on the cover of the transformer for the regulation of voltage without interruption to the supply.

Safety Protection Devices

Gas Relay: Provides automatic protection in case of gas accumulation inside the transformer.
Pressure Relief Valve: Provides transformer protection through the release of excess pressure when needed.

Oil Protection Devices

Oil Storage Tank: An integrated oil level gauge monitors the condition of the oil.

Moisture Absorber: The device is fitted with an oil seal that blocks moisture entry into the storage tank for the oil to ensure its quality is preserved.
Oil Temperature Monitoring
Oil temperature measuring glass thermometer tube fitted at top of the oil tank (position 120 ± 10mm depth).

A transformer with a rating of 1000kVA and above will be equipped with an outdoor signal thermometer.

Transformer Tank and Accessories

Construction of the tank: According to GB6451-1999, the construction of the tank shall allow proper position welding to keep the structural strength.
Oil Sample Valve: Situated on the oil tank lower wall for easy sampling.
Oil Drainage Valve: Big oil discharge valve at the bottom of the tank for smooth draining and maintenance of oil.
This SZ11-35KV oil-immersed transformer has robust design features and safety mechanisms, thereby ensuring long-term reliability for efficient performance in substation and power distribution applications.