Exclusive: Brazil grid operator wants 662 GE transformers removed after explosions - document

By Luciano Costa

SAO PAULO (Reuters) - Brazil's power system operator has requested that 662 transformers made by General Electric Co be removed from the country's grid after a number of explosions involving the devices, according to document seen by Reuters.

The document, which was prepared by Brazil's grid operator ONS and submitted to the Ministry of Mines and Energy in early December, says 53 GE transformers have exploded in the past six years, suggesting that the incidents may be associated with the product or its materials. They are all the same transformer model.

There is no evidence that anyone was injured in those explosions.

ONS confirmed in a statement that it had made the request to change some GE transformers after finding they "present a failure rate that is superior to what is expected for that equipment." It did not specify the number of transformers or incidents that led to the request.

GE said it was aware of the incidents but that it had not seen the ONS report."Currently, there is no evidence that the cause could be related to the design, the materials or the product's manufacturing," GE said in a statement, after Reuters provided it with excerpts of the report. The company said the transformers were used around the world.

GE pointed to the concentration of incidents in "one part of Brazil's electric network."

The problem has been on ONS's radar since 2014 and it concluded that similar incidents had not been recorded with other transformer manufacturers or different GE models, according to the document, which Reuters obtained through Brazil's access to public information law.

A source at a local utility, who requested anonymity to speak freely, said that the position of his employer and its peers is that "there is a systemic problem with the manufacturer, and not with the operators."

The source said the company had taken measures to avoid potential harm from the explosions.

ONS's recommendation comes as GE tries to restructure its struggling power division amid falling revenues and it follows reports of problems with other products, including gas turbines in several countries.

(Reporting by Marcelo Rochabrun; Editing by Susan Thomas)