Tag Archives: dry-type transformer

Trafo powers through at Mpumalanga coal mine

Trafo Power Solutions says it has recently completed a dry-type transformer contract as part of a significant upgrade at a coal mine, in Mpumalanga, South Africa.

This involved the design, supply and installation of two 200 kVA – 22 kV-400 V – dry-type transformers, according to Trafo Power Solutions Managing Director, David Claassen. Housed in specialised IP42-rated ingress protected enclosures, the units were specified by a design house on behalf of the end-customer, the dry-type transformer leader said.

“The contract demonstrated our application engineering capability and our experience in co-ordinating our solution within a larger project,” Claassen said. “This included meeting detailed specifications, and ensuring that our design for the transformers and their enclosures matched the requirements and constraints of the site.”

Trafo Power Solutions also equipped the units with the necessary earth fault protection and surge protection, as well as vibration pads, it said.

“Dry-type transformers are well suited for the coal mining environment, with its hazardous areas and its regulations to mitigate fire risk,” Claassen says. “The dry-type technology uses air to cool the transformers, doing away with the need to use oil as a coolant.”

Claassen emphasised that the absence of oil has advantages for safety, as the oil ignition potential is removed. The units can also be protected against fine airborne coal dust. An added environmental advantage is the lack of oil leaks contaminating the ground or water, too.

Trafo transforms fortunes at KwaZulu-Natal mining operation

Trafo Power Solutions recently came to the aid of a mining company in KwaZulu-Natal, South, Africa, suffering from a transformer failure.

Following the incident, dry-type transformer specialist, Trafo, designed, built and delivered a non-standard cast-resin replacement for the company – in just five weeks.

David Claassen, Managing Director of Trafo Power Solutions, said: “Once the situation with the old transformer was assessed, it was decided it would be more economical to replace the unit than to embark on major repairs.

“We were able to accommodate the customer’s specifications in our replacement design, and have the unit manufactured by our European partners (the TMC transformers facility, in Italy, pictured) in just four weeks. After that, it took just a week to fly in the transformer and deliver it to the customer.”

Claassen said it is not uncommon for transformer replacements of this scale to take anything from 12 to 14 weeks, with Trafo’s rapid turnaround time highly valued by the customer.

The mine required a 1,600 kVA dry-type DYN11 transformer that stepped 33 kV down to 550 V, with a non-standard tap setting arrangement of seven tap settings instead of the normal five.

Dry-type transformers – also called cast-resin transformers – are growing in popularity as users recognise their safety benefits, as well as their economy and flexibility of placement, according to Trafo. To meet this demand, Trafo works in close collaboration with established and well-resourced manufacturing partners in Europe to source tailored designs that meet customers’ exacting specifications, it said. This comes on top of ongoing after-sales service.