Delivering stable power to communities with every single phase pad mounted transformer
01 General
1.1 Project Description
In 2024, scotech delivered 10 units of 50 kVA single-phase pad-mounted transformers to a customer in Jamaica. Each transformer was designed and built to meet IEEE standards. They offer dependable performance and long service life.
They serve as medium-voltage distribution transformers within underground power distribution systems. Equipped with a primary winding voltage of 24GrdY/13.8 kV and a secondary winding voltage of 0.24/0.12 kV, providing 50 kVA of output power.
Dead-front transformers feature fully enclosed electrical connections and components, with no exposed live parts or terminals when the front door is opened. A loop-feed design enhances safety, reliability, and flexibility in distribution networks.
The 50 kVA single phase pad mounted transformer is built with copper windings for strong electrical performance. The transformer is equipped with an efficient ONAN cooling system, complemented by high-quality mineral oil and low PCB level, thus ensuring safe and environmentally friendly operation. Furthermore, the on-load loss value remains under 0.35 kW, and the no-load loss value does not exceed 0.13 kW.
About the protection system, these transformers have a bayonet fuse, a current limiting fuse (CLF), and a pressure relief device. These parts give protection against overcurrents and lower the risk of damage from short circuits or other faults.
1.2 Technical Specification
50kVA single phase pad mounted transformer specification and data sheet
| Delivered to | Jamaica |
| Year | 2024 |
| Type | single phase pad mount transformer |
| Standard | IEEE Std |
| Rated Power | 50kVA |
| Frequency | 50HZ |
| Feed | Loop |
| Front | Dead |
| Cooling Type | ONAN |
| Liquid insulant | Mineral Oil |
| Primary Voltage | 24GrdY/13.8 |
| Secondary Voltage | 0.24/0.12 KV |
| Vector Group | Ii0 |
| Polarity | Subtractive |
| Winding Material | Copper |
| Impedance | 4% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 0.13 KW |
| On Load Loss | 0.35 KW |
| Accessories | IFD ，Surge arrester |
1.3 Drawings
50kVA single phase pad mounted transformer dimensions and weight details
02 Manufacturing
2.1 Core
 | Cores shall be clamped and braced to resist distortion caused by shortcircuit stresses or transportation handling and to prevent the shifting of core laminations. |
2.2 Winding
Our 50 kVA single phase pad mounted transformer windings use high-purity enameled round copper wire, featuring excellent electrical conductivity and compact insulation. Strong enamel adhesion improves durability and wear resistance.
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2.3 Tank
 | All enclosures are constructed from mild steel and have a powder-coated finish to provide a durable, tamper-resistant surface. A fixed tray, designed to retain 100ml of insulating fluid and prevent the fluid from dripping down the tank wall or onto accessories, shall be installed below the location of each withdrawable fuse. Scotech pad-mounted transformers withstand both tampering and harsh weather, making them safe for installation in public areas. |
2.4 Elbow Arrester
Elbow arresters protect transformer insulation systems and underground cables from lightning surges, switching overvoltage, and grid disturbances. In tropical regions like Jamaica, they help reduce insulation aging and equipment damage by safely grounding surge energy. Their shielded deadfront design also improves operational safety and supports reliable underground distribution performance.
2.5 Final Assembly
This transformer shall be protected by a two-fuse protection system consisting of a bayonet oil-immersed, expulsion fuse in series with an oil-immersed, partial-range, current-limiting fuse. Bayonet fuse links shall sense both high currents and high oil temperature in order to provide thermal protection to the transformer. |  |
03 Packing And Shipping
3.1 Packing
1. Wooden Crate Packaging: Transformers are typically packaged in sturdy wooden crates, which effectively protect against external pressure during transportation. The interior of the crates is often lined with foam or sponge to absorb impact. 2. Waterproof Materials: Waterproof packaging is particularly important during ocean transportation. Transformers are often covered with a waterproof film or moisture-proof material to prevent moisture and scratches during transit. 3. Reinforcement Materials: More delicate transformers are reinforced with steel bars or iron frames to prevent damage from collisions and crushing during transportation. 4. Labeling and Labeling: The packaging will be labeled with prominent shipping labels, such as “Fragile,” “Heavy,” or “Keep Upright,” to remind transporters to handle with care.
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3.2 Shipping
 | 1. Loading and unloading: The hoisting equipment is used in the loading and unloading process to ensure that there is no additional mechanical stress during the transportation of the transformer. 2. Fixed: During transportation, the transformer needs to be properly fixed to prevent tilt or collision, resulting in mechanical damage. 3. Protection: Measures need to be taken to protect the insulated part of the transformer and the external structure to prevent contamination or damage. |
04 Site and Summary
This 50 kVA single phase pad mounted transformer is made with copper windings and a strong steel tank. The core uses high-grade silicon steel, which keeps loss and noise low. The ONAN cooling system and mineral oil help the unit run safely and last long.
It has a dead-front, loop-feed design. The unit has fuses, a pressure relief device, and can include extra parts like surge arresters and fault detectors. These give good protection against faults and make the unit more reliable.
This transformer is safe, strong, and efficient. It gives steady power to local homes and businesses in Jamaica. It is a good choice for long-term power use.
