The review of the DC power business, which ABB confirmed on Wednesday, is part of interim CEO Peter Voser's overhaul of the group's underperforming businesses that generate $3 billion (£2.4 billion) of revenue - equivalent to 11% of the company's total annual sales.

Earlier this month, ABB said it would pay up to $470 million to hand over its loss-making solar inverter business to Italy's FIMER SpA, Voser's first big move to revive ABB, whose share price has lost nearly 13% in recent years.

The maker of industrial robots and electrification products is also in the middle of selling its power grids business to Japan's Hitachi and reorganising its remaining operations into four divisions.

Voser told Reuters earlier this month that ABB's operational performance had been "unsatisfactory" in recent years, a situation he was determined to fix.

A sale is one of the options for the DC power business, which makes power converters for the telecoms industry. It was acquired when ABB bought General Electric Industrial Solutions' business in 2017.

"This, however, is not an indication that this process will definitely end in a transaction, nor a reflection on the timing and terms of any deal," ABB said in a statement.

ABB gave no details on the size of the business, which is part of its electrification division, or details of customers.

ABB is due to report second-quarter earnings on Thursday.

(Reporting by John Revill; Editing by Susan Fenton and Jane Merriman)

By John Revill