Workers were told ABB is transferring the large-scale production of traction transformers, used by trains, to its site in Lodz over the next three years.

ABB cited increasing competition and "challenging" market conditions for the decision. The Geneva factory belongs to ABB's Power Grids division, currently the least profitable of its four businesses, having suffered a 9 percent drop in orders this year.

The rest of the Geneva factory, which makes chargers for electric buses that are soon to start running in Geneva this month, will not be affected by the restructuring.

Around 112 jobs will remain in Geneva, which will also continue to carry out research and development as well as small-scale production. Sales and marketing will not be affected.

"This plan is based on challenging market conditions resulting from external factors, loading of the factory and sustaining competitiveness," ABB said.

"The overall market and investment climate, coupled with changing market dynamics and buying patterns, with local procurement in growth markets like India and China, is affecting the viability of the Geneva traction transformer factory to remain competitive."

ABB, which employs around 6,000 people in Switzerland, said its other factories in the country are unaffected.

(Reporting by John Revill, editing by Louise Heavens)