Supplying an engineering, procurement and construction (EPC) contractor, Trafo Power Solutions is providing 13 dry-type transformers for inclusion in e-houses on a remote mine site in Pakistan. The project is located in the Chagai district of Balochistan, close to the borders of Afghanistan and Iran, with terrain that is arid and semi-arid, characterised by deserts, mountain ranges, sparse vegetation and regular dust storms.

According to Trafo Power Solutions MD David Claassen the transformers have been designed to meet the challenges of this remote and demanding mining environment.

“The range of dry-type transformers that we are supplying to this copper/gold project in its early works phase of development includes smaller isolation transformers rated at 5 kVA, lighting transformers of 75 kVA, and larger units of between 250 kVA and 1 000 kVA for power distribution functions,” Claassen says.

He explains that the company designed the transformers for indoor operation in the e-houses but also took into account the high ambient temperatures of the site, catering for daytime temperatures of over 50 °C, with Class H insulation.

“To improve the turnaround time, we manufactured the enclosures in South Africa and importantly these could be flat-packed for easier logistical handling to site,” notes Claassen. “The dry-type transformers were shipped by our manufacturing partners TMC Transformers in Italy, directly to the site in Pakistan.”

He highlights that while the manufacturing of the transformers takes place in Italy, Trafo Power Solutions conducts the factory acceptance testing with the customer. The order also includes 18 neutral earth resistors (NERs) which are connected to the star point of the transformers to limit the earth fault current.

“We are supplying a number of 690 V air-type NERs as well as 11 kV NERs which are rated at 300 A for 10 seconds – also capable of operating in air temperatures of up to 50 °C,” Claassen says.

He points to the reliability of dry-type transformers as an important benefit to users on remote sites such as this one in Pakistan, as well as the limited maintenance they require. Unlike conventional oil-cooled transformers, where the oil needs regular testing and replacement, dry-type units are air-cooled and seldom require any active maintenance.

Claassen affirms that Trafo Power Solutions will provide technical support and will work closely with its EPC customer to ensure that the transformers are adequately protected from the severe external environment conditions such as heat and dust.