25kVA pole mounted transformer - dual-voltage with IFD, engineered for reliable, safe, and long-lasting rural power distribution
01 General
1.1 Project Description
In 2025, SCOTECH supplied a 25kVA single-phase pole mounted transformer for a Canadian utility distribution project.
The project followed CSA C2.2-06 standards and the requirements of the local Canadian utility. We paid special attention to surge protection, insulation reliability, and outdoor safety-because in rural areas, you never know what the weather or wildlife might throw at you.
Installed on a distribution pole along a rural feeder line, this transformer steps down medium voltage to 120/240 V for residential service. It’s built specifically for overhead distribution networks in low-density areas, where stable voltage and environmental durability are critical-and yes, wildlife protection too.
Since these poles are exposed to lightning, switching surges, and sometimes curious animals, we equipped the unit with a high-performance surge arrester and wildlife guards. This setup keeps the transformer reliable over the long term and helps reduce the risk of outages, even in tough conditions.
1.2 Technical Specification
25kVA pole mounted transformer specification and data sheet
| Delivered to | Canada |
| Year | 2025 |
| Type | Pole mounted transformer |
| Standard | CSA C2.2-06 |
| Rated Power | 25KVA |
| Frequency | 60HZ |
| Phase | Single |
| Cooling Type | ONAN |
| Liquid insulant | Mineral Oil |
| Primary Voltage | 2.4*7.2-0.12/0.24kV |
| Secondary Voltage | 120/240 V |
| Vector Group | Ii6 |
| Winding Material | Aluminum |
| Impedance | 2.02%(±10%) |
| Efficiency | ≥ 98.63% |
| Tap Changer | NLTC |
| No Load Loss | 104 W |
| Load Loss at Rated Voltage | 309 W |
| Accessories | Dual-voltage transformer with IFD |
1.3 Drawings
25 kVA pole mounted transformer dimensions and weight details
02 Manufacturing
2.1 Winding
 | Coil setup: LV foil, HV wire, mix of copper and aluminum. Foil spreads current, sheds heat. Wire bends, stays insulated. Copper-aluminum blend hits efficiency and cost right. Durable. Works in urban streets, rural lines, whatever the day throws at it. Reliable, steady, doing its job without fuss. |
2.2 IFD
| This 25kVA pole mounted transformer is equipped with an optional Internal Fuse Device (IFD), selected to provide additional protection for the transformer windings. The IFD acts as a safeguard against internal short-circuits or overloads, disconnecting the affected winding section without impacting the rest of the system. This feature enhances operational reliability, especially in remote or rural overhead distribution networks, and was chosen for this project to meet the customer’s specific safety and performance requirements. |  |
2.3 Tank
 | The oil tank was manufactured in SCOTECH’s own tank workshop following a precise production process: the steel plates were first cut to size, drilled, bent, and rolled into shape, then welded into a complete tank. After welding, our skilled technicians manually removed slag, as shown in the accompanying photo, and the tank was further prepared through grinding and shot-blasting. Finally, a powder coating was applied, and the finished tank underwent thorough inspection to ensure long-term outdoor durability, corrosion resistance, and overall quality. |
2.4 9kV HV Arrester
To protect the 25kVA pole mounted transformer operating on a 7.2 kV primary distribution system, a 9 kV class surge arrester was selected and installed on the primary side.
The arrester keeps lightning impulse overvoltages below 30 kV, which means the transformer’s insulation stays protected and its service life gets a real boost—especially out there on exposed poles where storms can hit hard.
And because these installations are outdoors, and animals—well, they’re curious—we added wildlife guards on the primary bushings and the arrester itself. This way, the risk of animal-related faults drops, and the transformer stays safe and reliable. It’s exactly the kind of protection you need for rural and suburban distribution networks.
03 Distribution Structure Standard
| Item | Description | Quantity |
| 1 | Cutout, Load Break | 1 |
| 2 | Fuse | 1 |
| 3 | Arrester, Polymer, 18 kV, 15.3 kV MCOV (Size to Primary Voltage) | 1 |
| 4 | Transformer (Size and Ratings Specified on Site Plan) | 1 |
| 5 | Clamp, Stirrup, #6 to 3/0 | 1 |
| 6 | Clamp, Hot Line, #8 to 2/0 | 1 |
| 7 | Connector, Compression, H-Tap, #2–6 ACSR to #1–6 STR | 3 |
| 8 | Bracket, Cutout, Welded, Pole-Mounted, 12″ Length | 1 |
| 9 | Cable / Wire, Drop Leads | 9 |
| 10 | Cable, #2, Stranded Copper, Black, RW90 | 9 |
| 11 | Cable, #2, Stranded Copper, Green, RW90 | 3 |
| 12 | Bracket, Tank-Mounted Arrester, 2-1/4″ Offset, 7-1/2″ Length | 1 |
| 13 | Wildlife Guard, Transformer Bushing | 1 |
| Bolt, Machine, 3/4″ Dia. (Length as Required), c/w Square Nut | As Required | |
| Washer, Lock, 3/4″ Nom., Helical Spring, Galv. CSAG164M | As Required | |
| Washer, Square, Flat, 3/4″ Nom. | As Required | |
| Bolt, Lag, 1/2″ Dia., 4-1/2″ Length | 1 |
04 Packing And Transportation
4.1 Packing
4.2 Shipping
