War, peace and ballasts
The Winter War (World War II) interrupted the rapid expansion of production. Between 1940–1950, Helvar concentrated on the supply radio equipment to the Finnish armed forces, and in payment of Finnish war debts to the Soviet Union.
In the next five years, Helvar restarted consumer production while reorganizing the electrical department, founded in 1947. Due to shortage of materials, consumer production was slow. Not until 1950 was a new radio annual production record of 30 000 sets achieved.
The department of electrical equipment was considered to be a separate business line and production of ballasts and contactors began in 1949–1950.
Lighting took a significant leap forward in the 1930s, when the fluorescent lamp was developed in the United States. But it was not until after the war, at the end of the 1940s, that this type of lighting became common in Finland, and in 1949 Helvar finally started production of ballasts for fluorescent lamps.