-
ProductsService and SupportBusiness consultation hotline：
-
-
Service and SupportBusiness consultation hotline： -
Support
Service and SupportBusiness consultation hotline： -
Service and SupportBusiness consultation hotline：
Comprehensive Guide to Distribution Transformers: Types, Installation, and Applications
Classification:
Industry News
Release time:
2025-01-15
Distribution Transformer, abbreviated as "distribution transformer," refers to a stationary electrical device in the distribution system that transforms three-phase AC voltage and current for transmitting AC power based on the principle of electromagnetic induction. A distribution transformer typically operates in a distribution network with a voltage level of 10-35kV (mostly 10kV and below) and a capacity of 6300 kVA or less, supplying power directly to end-users.
Classification by Installation Location
Distribution transformers are classified by their installation locations into indoor and outdoor types.
Outdoor installations can be further categorized into pole-mounted, pedestal-mounted, and ground-mounted (including pre-installed) types.
Pole-Mounted
Pole-mounted transformers are installed on a frame mounted on poles. They are divided into single-pole and double-pole installations:
1，For transformers with a capacity of 30 kVA or below (including 30 kVA), a single-pole setup is generally used. The transformer, high-voltage dropout fuse, and high-voltage arrester are mounted on a single concrete pole, which should tilt 13°–15° in the opposite direction of the transformer assembly.
2，For transformers with capacities ranging from 50 kVA to 315 kVA, a double-pole structure is commonly employed. The transformer platform comprises a main concrete pole and a secondary auxiliary pole. The main pole is equipped with a high-voltage dropout fuse and high-voltage down-lead, while the auxiliary pole carries secondary leads. The double-pole setup strengthens the single-pole configuration.
Advantages: Small footprint, no need for fences or enclosures, and elevated live parts reduce the risk of accidents.
Disadvantages: High use of steel materials, leading to higher costs.
Pedestal-Mounted
A pedestal-mounted installation places the transformer on a 0.5–1m brick or stone platform beneath the pole. This type is generally used for transformers above 315 kVA.
Precautions for Pedestal-Mounted Installations:
1，A sturdy enclosure or wall at least 1.8m high must surround the transformer. The door should be locked and managed by authorized personnel.
2，The enclosure or wall must provide sufficient safe operating distance from the transformer.
3，Warning signs such as "High Voltage Danger, Do Not Climb" must be displayed on poles or walls to prevent access by people or animals.
Advantages: Low cost and easy maintenance.
Disadvantages: Larger footprint and the risk of damage from external forces or small animals.
Ground-Mounted
In ground-mounted installations, the transformer is placed directly on the ground, with high-voltage down-leads, dropout fuses, and arresters installed on terminal poles.
Precautions for Ground-Mounted Installations:
1，A secure enclosure must surround the transformer, with locked doors managed by authorized personnel.
2，Warning signs such as "High Voltage Danger, Do Not Climb" must be displayed outside the enclosure.
3，Access inside the enclosure is only allowed after power has been disconnected, as live parts are positioned close to the ground.
Classification by Cooling Method
Transformers can be classified into oil-immersed and dry-type transformers based on their cooling methods.
Oil-Immersed Transformers
Oil-immersed transformers use oil as the cooling medium. Cooling methods include oil-immersed self-cooling, oil-immersed forced air cooling, oil-immersed water cooling, and forced oil circulation.
Types by Shell Design:
Non-Sealed Oil-Immersed Transformers: Series like S8, S9, and S10, widely used in industrial, agricultural, and civil buildings.
Sealed Oil-Immersed Transformers: Series like S9, S9-M, and S10-M, commonly used in oil-contaminated or chemically exposed environments.
Hermetically Sealed Oil-Immersed Transformers: Series like BS9, S9-, S10-, S11-MR, SH, and SH12-M, suitable for various industrial, agricultural, and civil applications.
Dry-Type Transformers
Dry-type transformers rely on air convection for natural cooling or enhanced cooling with fans. They are commonly used in high-rise buildings, toll stations, local lighting, and electronic circuits.
Types by Insulation Medium:
Encapsulated Coil Dry-Type Transformers: Series like SCB8, SC(B)9, SC(B)10, and SCR-10, suitable for high-rise buildings, commercial centers, airports, stations, subways, hospitals, and factories.
Non-Encapsulated Coil Dry-Type Transformers: Series like SG10, suitable for similar applications including petrochemical facilities.
Classification by Voltage Regulation Method
Transformers are classified as either on-load or off-load tap-changing types based on their voltage regulation methods.
Off-Load Tap-Changing: Requires the transformer to be powered off during tap switching.
On-Load Tap-Changing: Allows tap changes while under load.
Classification by Phase Number
Transformers are classified as single-phase or three-phase transformers.
Single-Phase Transformers: Both primary and secondary windings are single-phase. These are simple, compact, and have low losses, making them suitable for low-density low-voltage distribution networks.
Three-Phase Transformers: Designed for voltage changes in three-phase systems. The windings are connected in configurations such as delta, star, or extended delta, with voltage phase differences of 120°.
Keywords
WhatsApp：
Tel：
E-mail:
Address:
500 meters southeast of Yilong Bridge in Yichuan, Luoyang, China
8615896663407