300 kVA Oil Filled Transformer-13.2/0.48 kV | Guyana 2024

Reliable, durable, and energy-efficient – Three-Phase Pad-Mounted Transformer redefines the standards of power systems!

01 General

1.1 Project Description

300 kVA pad mounted transformer was delivered to South America in 2024. The rated power of the oil filled transformer is 300 kVA with ONAN cooling. The primary voltage is 13.2GrdY/7.62kV with ±2*2.5% tapping range (NLTC), the secondary voltage is 0.48/0.277kV, they formed a vector group of YNyn0, and it is a loop feed and dead front transformer. Oil filled transformer is compact and has a small footprint, making it particularly suitable for use in urban areas and places with limited space. Pad mounted transformer integrates transformers, high-voltage switchgear, low-voltage distribution equipment and auxiliary equipment in a single box, avoiding the problem of scattered layout of traditional substation equipment. Complete the overall assembly and commissioning of the equipment in the factory, and only need to connect high-voltage and low-voltage cables to the site to put into operation, greatly shortening the construction period. The design advantages of the American box transformer are mainly reflected in the compact structure design, high security, low maintenance cost and flexible expansion. These characteristics make it particularly suitable for application in urban power distribution, commercial complex, wind power, photovoltaic and other scenarios that require high space, reliability and efficiency.

Our 300 KVA pad mounted transformer was designed with advanced technology and adopts high quality material and components which result in reliable quality and long operation time.

1.2 Technical Specification

300 KVA oil filled transformer specifications type and data sheet

1.3 Drawings

300 KVA oil filled transformer diagram drawing and size.

02 Manufacturing

2.1 HV Bushing

Dead front apparatus for transformers enhances safety (reduces high-voltage exposure/arc flash risk) and enables smaller cabinet sizes via reduced bushing clearances. Less common in padmount transformers today, live front bushings are occasionally used for HV primary connections. Dead front interfaces (mostly 200A loadbreak; 600/900A non-loadbreak options) are rarely used for LV secondary terminations due to supporting only one cable per elbow connector (incompatible with multi-cable per phase setups).

2.2 LV Bushing Support

When low-voltage spades include more mounting holes, they generally grow longer in length. If your spades have multiple holes (and are therefore connected to several cables), adding low-voltage bushing supports becomes a necessary measure. Bushing supports are also a wise consideration if you’re working with spade extensions. An unsupported bushing can be strained by the weight of too many heavy cables attached to it. This excess weight may compress the bottom portion of the bushing’s gasket (which sits against the transformer tank wall). Over time, this compression can lead to transformer oil leaks that start from the top area of the gasket.

2.3 Tap Changer

Transformer tap changers function by selecting a setting aligned with the actual incoming voltage-this keeps the load’s output voltage matching the transformer’s rated nameplate value. If incoming voltage is too low: Rotate the HV cabinet’s tap changer to a lower setting. This disconnects small sections of the primary winding (reducing its turn count, while the secondary stays unchanged). The adjusted turn ratio boosts the secondary-side voltage, fixing the low input issue.

2.4 Final Assembly

This is a plug-in, current-limiting fuse installed on the transformer’s high-voltage side. It serves as backup protection against internal or secondary-side faults. Its key features include a bayonet-style design for safe manual replacement, rapid current interruption to limit fault energy, and a visual indicator (like a striker pin) to clearly show operation. The fuse is coordinated with the transformer’s rating to ensure selective tripping, providing a simple and reliable outdoor protection solution.

2.5 loadbreak switch

The loadbreak switch is a three-pole, SF6-insulated switching device mounted on the high-voltage side, designed for safely making and breaking load currents. Its key features include visible disconnect for isolation, dead-front construction for operator safety, an external rotary handle for manual operation, and integrated arc-quenching capability (typically using SF6 gas or vacuum). This switch allows for safe sectionalizing, transformer energization/de-energization, and fault isolation without requiring cable elbow removal, enhancing system flexibility and maintenance safety.

03 Testing

04 Packing and Shipping

05 Site And Summary

The Three Phase Pad Mounted Transformer, with its outstanding performance, safe design, and stable operation, is the ideal choice for power distribution. Whether in commercial, industrial, or public infrastructure applications, it reliably meets diverse needs, providing users with efficient, energy-saving, and cost-effective power solutions. Choose the Three Phase Pad Mounted Transformer to ensure safe and reliable power for your projects and to contribute strong momentum toward sustainable development in the future.